Cover Page
Cover Page | 9 Months Ended |
Sep. 30, 2023 | |
Document Type | S-1/A |
Amendment Flag | false |
Entity Registrant Name | Dianthus Therapeutics, Inc. |
Entity Central Index Key | 0001690585 |
Entity Filer Category | Non-accelerated Filer |
Entity Ex Transition Period | false |
Entity Emerging Growth Company | true |
Entity Small Business | true |
Entity Tax Identification Number | 81-0724163 |
Entity Incorporation, State or Country Code | DE |
Entity Address, Address Line One | 7 Times Square, 43rd Floor, |
Entity Address, City or Town | New York |
Entity Address, Postal Zip Code | 10036 |
Entity Address, State or Province | NY |
City Area Code | 929 |
Local Phone Number | 999-4055 |
Business Contact [Member] | |
Entity Address, Address Line One | 7 Times Square, 43rd Floor, |
Entity Address, City or Town | New York |
Entity Address, Postal Zip Code | 10036 |
Entity Address, State or Province | NY |
City Area Code | 929 |
Local Phone Number | 999-4055 |
Condensed Consolidated Balance
Condensed Consolidated Balance Sheets (unaudited) - USD ($) $ in Thousands | Sep. 30, 2023 | Dec. 31, 2022 | Dec. 31, 2021 |
Current assets: | |||
Cash and cash equivalents | $ 157,282 | $ 15,365 | $ 7,638 |
Short-term investments | 32,588 | 60,125 | 0 |
Receivable from related party | 232 | 4,700 | 469 |
Unbilled receivable from related party | 519 | 938 | 1,007 |
Prepaid expenses and other current assets | 832 | 905 | 274 |
Total current assets | 191,453 | 82,033 | 9,388 |
Property and equipment, net | 195 | 142 | 33 |
Right-of-use lease assets | 698 | 814 | 0 |
Other assets and restricted cash | 116 | 121 | 30 |
Total assets | 192,462 | 83,110 | 9,451 |
Current liabilities: | |||
Accounts payable | 1,369 | 1,167 | 1,359 |
Accrued expenses | 11,197 | 6,608 | 3,993 |
Current portion of deferred revenue—related party | 100 | 100 | 0 |
Current portion of lease liabilities | 413 | 350 | 0 |
Total current liabilities | 13,079 | 8,225 | 5,352 |
Deferred revenue—related party | 745 | 791 | 0 |
Long-term lease liabilities | 257 | 438 | 0 |
Total liabilities | 14,081 | 9,454 | 5,352 |
Commitments and contingencies (Note 15) | |||
Convertible preferred stock | 0 | 118,024 | 21,348 |
Stockholders' equity/(deficit): | |||
Preferred stock; par value per share – $0.001; authorized shares – 10,000,000 and none at September 30, 2023 and December 31, 2022, respectively; issued and outstanding shares – none | 0 | 0 | |
Common stock; par value per share—$0.001 and $0.0001 at September 30, 2023 and December 31, 2022, respectively; authorized shares – 150,000,000 and 8,722,279 at September 30, 2023 and December 31, 2022, respectively; issued and outstanding shares – 14,817,762 and 875,279 at September 30, 2023 and December 31, 2022, respectively | 15 | 0 | 0 |
Additional paid-in capital | 257,230 | 1,661 | 143 |
Accumulated deficit | (78,860) | (45,868) | (17,392) |
Accumulated other comprehensive loss | (4) | (161) | 0 |
Total stockholders' equity/(deficit) | 178,381 | (44,368) | (17,249) |
Total liabilities and stockholders' equity/(deficit) | $ 192,462 | 83,110 | 9,451 |
Series Seed One Redeemable Convertible Preferred Stock [Member] | |||
Current liabilities: | |||
Convertible preferred stock | 6,436 | 6,436 | |
Series Seed Two Redeemable Convertible Preferred Stock [Member] | |||
Current liabilities: | |||
Convertible preferred stock | 14,912 | 14,912 | |
Series A Redeemable Convertible Preferred Stock [Member] | |||
Current liabilities: | |||
Convertible preferred stock | $ 96,676 | $ 0 |
Condensed Consolidated Balanc_2
Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) | Sep. 30, 2023 | Dec. 31, 2022 | Dec. 31, 2021 |
Convertible preferred stock, par value | $ 0.0001 | $ 0.0001 | |
Convertible preferred stock, Shares authorized | 0 | 33,336,283 | |
Convertible preferred stock, Share issued | 0 | 33,336,282 | |
Convertible preferred stock, Shares Outstanding | 0 | 33,336,282 | |
Convertible preferred stock, Liquidation Preference | $ 0 | $ 121,500 | |
Preferred stock, par value | $ 0.001 | $ 0.001 | |
Preferred stock, par value | $ 0.0001 | $ 0.0001 | |
Preferred stock, Shares authorized | 10,000,000 | 33,336,283 | 10,329,266 |
Preferred stock, Shares issued | 0 | 0 | |
Preferred stock, Shares outstanding | 0 | 0 | |
Common stock, Par value | $ 0.001 | $ 0.0001 | $ 0.0001 |
Common stock, shares authorized | 150,000,000 | 8,722,279 | 3,706,968 |
Common stock, Shares issued | 14,817,762 | 875,279 | 875,279 |
Common stock, Shares outstanding | 14,817,762 | 875,279 | 875,279 |
Preferred stock, Shares authorized | 10,000,000 | 0 | |
Series Seed One Redeemable Convertible Preferred Stock [Member] | |||
Preferred stock, Shares authorized | 6,500,000 | 6,500,000 | |
Preferred stock, Shares issued | 6,500,000 | 6,500,000 | |
Preferred stock, Shares outstanding | 6,500,000 | 6,500,000 | |
Preferred Stock, Liquidation Preference, Value | $ 6,500,000 | $ 6,500,000 | |
Series Seed Two Redeemable Convertible Preferred Stock [Member] | |||
Preferred stock, Shares authorized | 3,829,265 | 3,829,265 | |
Preferred stock, Shares issued | 3,829,265 | 3,829,265 | |
Preferred stock, Shares outstanding | 3,829,265 | 3,829,265 | |
Preferred Stock, Liquidation Preference, Value | $ 15,000,000 | $ 15,000,000 | |
Series A Redeemable Convertible Preferred Stock [Member] | |||
Preferred stock, Shares authorized | 23,007,017 | ||
Preferred stock, Shares issued | 23,007,017 | ||
Preferred stock, Shares outstanding | 23,007,017 | ||
Preferred Stock, Liquidation Preference, Value | $ 100,000,000 | $ 100,000,000 |
Condensed Consolidated Statemen
Condensed Consolidated Statements of Operations and Comprehensive Loss (unaudited) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended | 12 Months Ended | |||
Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022 | Dec. 31, 2022 | Dec. 31, 2021 | |
Revenues: | ||||||
License revenue—related party | $ 924 | $ 1,173 | $ 2,369 | $ 5,242 | $ 6,417 | $ 1,476 |
Operating expenses: | ||||||
Research and development | 7,960 | 7,218 | 24,060 | 19,548 | 29,379 | 12,606 |
General and administrative | 8,723 | 2,209 | 13,527 | 4,706 | 6,743 | 1,956 |
Total operating expenses | 16,683 | 9,427 | 37,587 | 24,254 | 36,122 | 14,562 |
Loss from operations | (15,759) | (8,254) | (35,218) | (19,012) | (29,705) | (13,086) |
Other income/(expense): | ||||||
Interest income | 1,027 | 416 | 2,320 | 505 | 1,145 | 3 |
(Loss)/gain on currency exchange, net | (16) | 56 | (53) | 156 | 136 | (26) |
Other expense | (15) | (2) | (41) | (9) | (52) | 0 |
Total other income | 996 | 470 | 2,226 | 652 | 1,229 | (23) |
Net loss | $ (14,763) | $ (7,784) | $ (32,992) | $ (18,360) | $ (28,476) | $ (13,109) |
Net loss per share attributable to common stockholders, basic | $ (3.78) | $ (8.9) | $ (17.4) | $ (21) | $ (32.57) | $ (15.01) |
Net loss per share attributable to common stockholders, diluted | $ (3.78) | $ (8.9) | $ (17.4) | $ (21) | $ (32.57) | $ (15.01) |
Weighted-average number of common shares outstanding, used in computing net loss per common share, basic | 3,906,886 | 874,327 | 1,896,605 | 874,138 | 874,234 | 873,471 |
Weighted-average number of common shares outstanding, used in computing net loss per common share, diluted | 3,906,886 | 874,327 | 1,896,605 | 874,138 | 874,234 | 873,471 |
Comprehensive loss: | ||||||
Net loss | $ (14,763) | $ (7,784) | $ (32,992) | $ (18,360) | $ (28,476) | $ (13,109) |
Other comprehensive income/(loss): | ||||||
Change in unrealized losses related to available-for-sale debt securities | 15 | (150) | 157 | (150) | (161) | 0 |
Total other comprehensive income/(loss) | 15 | (150) | 157 | (150) | (161) | 0 |
Total comprehensive loss | $ (14,748) | $ (7,934) | $ (32,835) | $ (18,510) | $ (28,637) | $ (13,109) |
Condensed Consolidated Statem_2
Condensed Consolidated Statements of Changes in Convertible Preferred Stock and Stockholders' Equity/(Deficit) - USD ($) $ in Thousands | Total | Cumulative Effect, Period of Adoption, Adjusted Balance [Member] | Common Stock [Member] | Preferred Stock [Member] Convertible Preferred Stock [Member] | Preferred Stock [Member] Series Seed One Redeemable Convertible Preferred Stock [Member] | Preferred Stock [Member] Series Seed Two Redeemable Convertible Preferred Stock [Member] | Preferred Stock [Member] Series A Redeemable Convertible Preferred Stock [Member] | Preferred Stock [Member] Redeemable Convertible Preferred Stock [Member] | Additional Paid-in Capital [Member] | Accumulated Deficit [Member] | Accumulated Other Comprehensive Income (Loss) [Member] |
Beginning balance at Dec. 31, 2020 | $ (4,203) | $ 6,436 | $ 6,436 | $ 80 | $ (4,283) | ||||||
Beginning balance, shares at Dec. 31, 2020 | 875,279 | 6,500,000 | |||||||||
Issuance of convertible preferred stock, net of issuance costs | $ 14,912 | 14,912 | |||||||||
Issuance of convertible preferred stock, net of issuance costs, shares | 3,829,265 | ||||||||||
Stock-based compensation expense | 63 | 63 | |||||||||
Net loss | (13,109) | (13,109) | |||||||||
Ending balance at Dec. 31, 2021 | (17,249) | $ 0 | $ 21,348 | $ 6,436 | $ 14,912 | 21,348 | 143 | (17,392) | $ 0 | ||
Ending balance, shares at Dec. 31, 2021 | 875,279 | 875,279 | 10,329,265 | 6,500,000 | 3,829,265 | ||||||
Stock-based compensation expense | 65 | 65 | |||||||||
Net loss | (4,881) | (4,881) | |||||||||
Ending balance at Mar. 31, 2022 | (22,065) | $ 0 | $ 21,348 | 208 | (22,273) | 0 | |||||
Ending balance, shares at Mar. 31, 2022 | 875,279 | 10,329,265 | |||||||||
Beginning balance at Dec. 31, 2021 | (17,249) | $ 0 | $ 21,348 | $ 6,436 | $ 14,912 | 21,348 | 143 | (17,392) | 0 | ||
Beginning balance, shares at Dec. 31, 2021 | 875,279 | 875,279 | 10,329,265 | 6,500,000 | 3,829,265 | ||||||
Net loss | (18,360) | ||||||||||
Ending balance at Sep. 30, 2022 | (34,754) | $ 0 | $ 118,024 | 1,148 | (35,752) | (150) | |||||
Ending balance, shares at Sep. 30, 2022 | 875,279 | 33,336,282 | |||||||||
Beginning balance at Dec. 31, 2021 | (17,249) | $ 0 | $ 21,348 | $ 6,436 | $ 14,912 | 21,348 | 143 | (17,392) | 0 | ||
Beginning balance, shares at Dec. 31, 2021 | 875,279 | 875,279 | 10,329,265 | 6,500,000 | 3,829,265 | ||||||
Issuance of convertible preferred stock, net of issuance costs | $ 96,676 | 96,676 | |||||||||
Issuance of convertible preferred stock, net of issuance costs, shares | 23,007,017 | ||||||||||
Stock-based compensation expense | 1,518 | 1,518 | |||||||||
Net loss | (28,476) | (28,476) | |||||||||
Other comprehensive income (loss) | (161) | (161) | |||||||||
Ending balance at Dec. 31, 2022 | (44,368) | $ 0 | $ 118,024 | $ 6,436 | $ 14,912 | $ 96,676 | 118,024 | 1,661 | (45,868) | (161) | |
Ending balance, shares at Dec. 31, 2022 | 875,279 | 875,279 | 33,336,282 | 6,500,000 | 3,829,265 | 23,007,017 | |||||
Beginning balance at Mar. 31, 2022 | (22,065) | $ 0 | $ 21,348 | 208 | (22,273) | 0 | |||||
Beginning balance, shares at Mar. 31, 2022 | 875,279 | 10,329,265 | |||||||||
Issuance of convertible preferred stock, net of issuance costs | $ 96,676 | ||||||||||
Issuance of convertible preferred stock, net of issuance costs, shares | 23,007,017 | ||||||||||
Stock-based compensation expense | 279 | 279 | |||||||||
Net loss | (5,695) | (5,695) | |||||||||
Ending balance at Jun. 30, 2022 | (27,481) | 0 | $ 118,024 | 487 | (27,968) | ||||||
Ending balance, shares at Jun. 30, 2022 | 875,279 | 33,336,282 | |||||||||
Stock-based compensation expense | 661 | 661 | |||||||||
Net loss | (7,784) | (7,784) | |||||||||
Other comprehensive income (loss) | (150) | (150) | |||||||||
Ending balance at Sep. 30, 2022 | (34,754) | 0 | $ 118,024 | 1,148 | (35,752) | (150) | |||||
Ending balance, shares at Sep. 30, 2022 | 875,279 | 33,336,282 | |||||||||
Beginning balance at Dec. 31, 2022 | (44,368) | $ 0 | $ 118,024 | $ 6,436 | $ 14,912 | $ 96,676 | 118,024 | 1,661 | (45,868) | (161) | |
Beginning balance, shares at Dec. 31, 2022 | 875,279 | 875,279 | 33,336,282 | 6,500,000 | 3,829,265 | 23,007,017 | |||||
Stock-based compensation expense | 533 | 533 | |||||||||
Net loss | (7,089) | (7,089) | |||||||||
Other comprehensive income (loss) | 104 | 104 | |||||||||
Ending balance at Mar. 31, 2023 | (50,820) | $ 0 | $ 118,024 | 2,194 | (52,957) | (57) | |||||
Ending balance, shares at Mar. 31, 2023 | 875,279 | 33,336,282 | |||||||||
Beginning balance at Dec. 31, 2022 | (44,368) | $ 0 | $ 118,024 | $ 6,436 | $ 14,912 | $ 96,676 | $ 118,024 | 1,661 | (45,868) | (161) | |
Beginning balance, shares at Dec. 31, 2022 | 875,279 | 875,279 | 33,336,282 | 6,500,000 | 3,829,265 | 23,007,017 | |||||
Net loss | (32,992) | ||||||||||
Ending balance at Sep. 30, 2023 | 178,381 | $ 15 | $ 0 | 257,230 | (78,860) | (4) | |||||
Ending balance, shares at Sep. 30, 2023 | 14,817,762 | 0 | |||||||||
Beginning balance at Mar. 31, 2023 | (50,820) | 0 | $ 118,024 | 2,194 | (52,957) | (57) | |||||
Beginning balance, shares at Mar. 31, 2023 | 875,279 | 33,336,282 | |||||||||
Stock-based compensation expense | 462 | 462 | |||||||||
Net loss | (11,140) | (11,140) | |||||||||
Other comprehensive income (loss) | 38 | 38 | |||||||||
Ending balance at Jun. 30, 2023 | (61,460) | $ 118,024 | 2,656 | (64,097) | (19) | ||||||
Ending balance, shares at Jun. 30, 2023 | 875,279 | 33,336,282 | |||||||||
Exercise of common stock options | 5 | 1 | 4 | ||||||||
Exercise of common stock options, shares | 2,798 | ||||||||||
Conversion of convertible preferred stock to common stock in connection with the Reverse Merger | 118,024 | 1 | $ (118,024) | 118,023 | |||||||
Conversion of convertible preferred stock to common stock in connection with the Reverse Merger, shares | 7,269,183 | (33,336,282) | |||||||||
Issuance of common stock and pre-funded warrants in the pre-closing financing, net of issuance costs | 67,750 | 67,750 | |||||||||
Issuance of common stock and pre-funded warrants in the pre-closing financing, net of issuance costs, shares | 2,873,988 | ||||||||||
Issuance of common stock to former stockholders of Magenta Therapeutics, Inc. in connection with the Reverse Merger | 71,595 | 71,595 | |||||||||
Issuance of common stock to former stockholders of MagentaTherapeutics, Inc. in connection with the Reverse Merger, shares | 3,796,514 | ||||||||||
Adjustment for change in common stock par value in connection with the Reverse Merger | 13 | (13) | |||||||||
Reverse recapitalization transaction costs | (3,964) | (3,964) | |||||||||
Stock-based compensation expense | 1,179 | 1,179 | |||||||||
Net loss | (14,763) | (14,763) | |||||||||
Other comprehensive income (loss) | 15 | 15 | |||||||||
Ending balance at Sep. 30, 2023 | $ 178,381 | $ 15 | $ 0 | $ 257,230 | $ (78,860) | $ (4) | |||||
Ending balance, shares at Sep. 30, 2023 | 14,817,762 | 0 |
Condensed Consolidated Statem_3
Condensed Consolidated Statements of Changes in Convertible Preferred Stock and Stockholders' Equity/(Deficit) (Parenthetical) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended | ||
Sep. 30, 2023 | Jun. 30, 2022 | Dec. 31, 2022 | Dec. 31, 2021 | |
Stock issuance cost | $ 4,250 | |||
Convertible Preferred Stock [Member] | ||||
Stock issuance cost | $ 3,324 | |||
Series Seed Two Redeemable Convertible Preferred Stock [Member] | ||||
Stock issuance cost | $ 88 | |||
Series A Redeemable Convertible Preferred Stock [Member] | ||||
Stock issuance cost | $ 3,324 |
Condensed Consolidated Statem_4
Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands | 9 Months Ended | 12 Months Ended | ||
Sep. 30, 2023 | Sep. 30, 2022 | Dec. 31, 2022 | Dec. 31, 2021 | |
Cash flows from operating activities: | ||||
Net loss | $ (32,992) | $ (18,360) | $ (28,476) | $ (13,109) |
Adjustments to reconcile net loss to net cash used in operating activities: | ||||
Depreciation expense | 47 | 19 | 30 | 0 |
Stock-based compensation expense | 2,174 | 1,005 | 1,518 | 63 |
Accretion of discount on short-term investments | (896) | (204) | (606) | |
Amortization of right-of-use lease assets | 205 | 79 | 117 | |
Changes in operating assets and liabilities: | ||||
Receivable from related party | 4,468 | (1,083) | (4,231) | (469) |
Unbilled receivable from related party | 419 | (1,927) | 69 | (1,007) |
Prepaid expenses and other current assets | 2,546 | (862) | (631) | (271) |
Other assets | 10 | (49) | (31) | (30) |
Accounts payable, accrued expenses and lease liabilities | (942) | 249 | 2,280 | 4,919 |
Deferred revenue—related party | (46) | 914 | 891 | 0 |
Net cash used in operating activities | (25,007) | (20,219) | (29,070) | (9,904) |
Cash flows from investing activities: | ||||
Capital expenditures | (100) | (110) | (139) | (33) |
Purchases of short-term investments | (31,195) | (47,044) | (61,680) | 0 |
Proceeds from maturities of short-term investments | 59,785 | 0 | 2,000 | 0 |
Net cash provided by/(used in) investing activities | 28,490 | (47,154) | (59,819) | (33) |
Cash flows from financing activities: | ||||
Proceeds from exercise of stock options | 5 | 0 | ||
Proceeds from the pre-closing financing | 72,000 | 0 | ||
Payment of issuance costs in connection with pre-closing financing | (50) | 0 | ||
Cash acquired in connection with the reverse recapitalization | 69,738 | 0 | ||
Payment of reverse recapitalization transaction costs | (3,254) | 0 | ||
Proceeds from issuance of promissory notes payable to related party | 377 | 0 | ||
Repayment of promissory notes payable to related party | (377) | 0 | ||
Proceeds from issuance of Series A convertible preferred stock | 0 | 100,000 | ||
Payment of issuance costs for Series A convertible preferred stock | 0 | (3,324) | ||
Net cash provided by financing activities | 138,439 | 96,676 | 96,676 | 14,912 |
Increase in cash, cash equivalents and restricted cash | 141,922 | 29,303 | 7,787 | 4,975 |
Cash, cash equivalents and restricted cash, beginning of period | 15,425 | 7,638 | 7,638 | 2,663 |
Cash, cash equivalents and restricted cash, end of period | 157,347 | 36,941 | 15,425 | 7,638 |
Supplemental Disclosure | ||||
Cash and cash equivalents | 157,282 | 36,881 | 15,365 | 7,638 |
Restricted cash | 65 | 60 | 60 | 0 |
Total cash, cash equivalents and restricted cash | 157,347 | 36,941 | 15,425 | 7,638 |
Cash paid for interest | 0 | 0 | 0 | 0 |
Cash paid for taxes | 0 | 0 | 0 | 0 |
Issuance costs in connection with pre-closing financing included in accrued expenses | 4,200 | 0 | ||
Transaction costs related to reverse recapitalization included in accounts payable and accrued expenses | 710 | 0 | ||
Conversion of convertible preferred stock into common stock | 118,024 | 0 | ||
Additions to right-of-use lease assets from new operating lease liabilities | $ 89 | $ 931 | 931 | 0 |
Series A Redeemable Convertible Preferred Stock [Member] | ||||
Cash flows from financing activities: | ||||
Proceeds from issuance of convertible preferred stock | 100,000 | |||
Payment of issuance costs in connection with pre-closing financing | $ (3,324) | |||
Series Seed Two Redeemable Convertible Preferred Stock [Member] | ||||
Cash flows from financing activities: | ||||
Proceeds from issuance of convertible preferred stock | 15,000 | |||
Payment of issuance costs in connection with pre-closing financing | $ (88) |
Organization, Description of Bu
Organization, Description of Business and Liquidity | 9 Months Ended | 12 Months Ended |
Sep. 30, 2023 | Dec. 31, 2022 | |
Nature of the Business and Basis of Presentation | 1. Organization, Description of Business and Liquidity Business Dianthus Therapeutics, Inc. (formerly Magenta Therapeutics, Inc.) (the “Company” or “Dianthus”) is a clinical-stage biotechnology company focused on developing next-generation complement therapeutics for patients with severe autoimmune and inflammatory diseases. The Company’s corporate headquarters are in New York, New York. Currently, the Company is devoting substantially all efforts and resources toward product research and development of its product candidates. The Company has incurred losses from operations and negative operating cash flows since its inception. There can be no assurance that its research and development programs will be successful, that products developed, if any, will obtain necessary regulatory approval, or that any approved product, if any, will be commercially viable. In addition, the Company operates in an environment of rapid technological change and is largely dependent on the services of its key employees, consultants, and advisors. Reverse Merger and Pre-Closing On September 11, 2023, the Company completed its business combination with Dianthus Therapeutics, OpCo Inc. (formerly Dianthus Therapeutics, Inc.) (“Former Dianthus”) in accordance with the terms of the Agreement and Plan of Merger, dated as of May 2, 2023 (the “Merger Agreement”), by and among the Company, Dio Merger Sub, Inc., a Delaware corporation and a wholly owned subsidiary of the Company (“Merger Sub”), and Former Dianthus, pursuant to which, among other matters, Merger Sub merged with and into Former Dianthus, with Former Dianthus surviving as a wholly owned subsidiary of the Company (the “Reverse Merger”). In connection with the completion of the Reverse Merger, the Company changed its name from “Magenta Therapeutics, Inc.” to “Dianthus Therapeutics, Inc.,” and the business conducted by the Company became primarily the business conducted by Former Dianthus. Unless context otherwise requires, references herein to “Dianthus,” the “Company,” or the “combined company” refer to Dianthus Therapeutics, Inc. (formerly Magenta Therapeutics, Inc.) after completion of the Reverse Merger, the term “Former Dianthus” refers to Dianthus Therapeutics OpCo, Inc. (formerly Dianthus Therapeutics, Inc.), and the term “Magenta” refers to the Company prior to completion of the Reverse Merger. The Company was incorporated in June 2015 and Former Dianthus was incorporated in May 2019. Immediately prior to the effective time of the Reverse Merger, the Company effected a 1-for-16 At the effective time of the Reverse Merger, the Company issued an aggregate of 11,021,248 shares of Company common stock to the Former Dianthus stockholders, based on the exchange ratio of approximately 0.2181 shares of Company common stock for each share of Former Dianthus common stock, including those shares of Former Dianthus common stock issued upon the conversion of Former Dianthus preferred stock and those shares of the Former Dianthus common stock issued in the pre-closing At the effective time of the Reverse Merger, the 2019 Stock Plan (as discussed in Note 12) was assumed by the Company, and each outstanding and unexercised option to purchase shares of Former Dianthus common stock immediately prior to the effective time of the Reverse Merger was assumed by the Company and converted into an option to purchase shares of Company common stock, with necessary adjustments to the number of shares and exercise price to reflect the exchange ratio, and each outstanding and unexercised warrant to purchase shares of Former Dianthus common stock immediately prior to the effective time of the Reverse Merger (including the Former Dianthus pre-funded pre-closing The Reverse Merger was accounted for as a reverse recapitalization in accordance with generally accepted accounting principles in the United States of America (“U.S. GAAP”). Under this method of accounting, Former Dianthus was deemed to be the accounting acquirer for financial reporting purposes. This determination was primarily based on the expectation that, immediately following the Reverse Merger: (i) Former Dianthus’ stockholders own a substantial majority of the voting rights in the combined company; (ii) Former Dianthus’ largest stockholders retain the largest interest in the combined company; (iii) Former Dianthus designated a majority (six of eight) of the initial members of the board of directors of the combined company; and (iv) Former Dianthus’ executive management team became the management team of the combined company. Accordingly, for accounting purposes: (i) the Reverse Merger was treated as the equivalent of Former Dianthus issuing stock to acquire the net assets of Magenta; (ii) the net assets of Magenta are recorded at their acquisition-date fair value in the unaudited condensed consolidated financial statements of Former Dianthus and (iii) the reported historical operating results of the combined company prior to the Reverse Merger are those of Former Dianthus. Additional information regarding the Reverse Merger is included in Note 3. Historical common share figures of Former Dianthus have been retroactively restated based on the exchange ratio of approximately 0.2181. On September 11, 2023, prior to the effective time of the Reverse Merger, the Company entered into a contingent value rights agreement (the “CVR Agreement”) with a rights agent, pursuant to which pre-Reverse non-transferable pre-Reverse pre-Reverse Concurrently with the execution and delivery of the Merger Agreement, and in order to provide Former Dianthus with additional capital for its development programs, Former Dianthus entered into a subscription agreement, as amended (the “Subscription Agreement”), with certain investors named therein (the “Investors”), pursuant to which, subject to the terms and conditions of the Subscription Agreement, immediately prior to the effective time of the Reverse Merger, Former Dianthus issued and sold, and the Investors purchased, (i) 2,873,988 shares of Former Dianthus common stock and (ii) 210,320 pre-funded “pre-closing Risks and Uncertainties The Company is subject to risks and uncertainties common to early-stage companies in the biotechnology industry including, but not limited to, uncertainty of product development and commercialization, lack of marketing and sales history, development by its competitors of new technological innovations, dependence on its key personnel, market acceptance of products, product liability, protection of proprietary technology, ability to raise additional financing and compliance with government regulations. If the Company does not successfully commercialize any of its product candidates, it will be unable to generate recurring product revenue or achieve profitability. The Company’s potential product candidates that are in development require significant additional research and development efforts, including extensive preclinical and clinical testing and regulatory approval prior to commercialization. These efforts require significant amounts of additional capital, adequate personnel and infrastructure, and extensive compliance-reporting capabilities. Even if its product development efforts are successful, it is uncertain when, if ever, the Company will generate revenue from product sales. Liquidity In accordance with Accounting Standards Update No. 2014-15, Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern 205-40), • Since its inception, the Company has funded its operations primarily with outside capital and has incurred significant recurring losses, including net losses of $33.0 million and $ 18.4 • The Company expects to continue to incur significant recurring losses and rely on outside capital to fund its operations for the foreseeable future; and • As of the issuance date, the Company expects that its existing cash, cash equivalents and short-term investments on hand as of the issuance date will be sufficient to fund its obligations as they become due for at least twelve months beyond the issuance date. The Company expects that its research and development and general and administrative costs will continue to increase significantly, including in connection with conducting clinical trials and manufacturing for its existing product candidate and any future product candidates to support commercialization and providing general and administrative support for its operations, including the costs associated with operating as a public company. In the event the Company is unable to secure additional outside capital, management will be required to seek other alternatives which may include, among others, a delay or termination of clinical trials or the development of its product candidates, temporary or permanent curtailment of the Company’s operations, a sale of assets, or other alternatives with strategic or financial partners. The accompanying unaudited condensed consolidated financial statements do not include any adjustments that might result from the outcome of these uncertainties. Accordingly, the unaudited condensed consolidated financial statements have been prepared on a basis that assumes the Company will continue as a going concern and which contemplates the realization of assets and satisfaction of liabilities and commitments in the ordinary course of business. | 1. Nature of Organization and Operations Dianthus Therapeutics, Inc. (“Dianthus” or the “Company”) is a clinical-stage biotechnology company focused on developing next-generation complement therapeutics for patients with severe autoimmune and inflammatory diseases. Dianthus was incorporated in the State of Delaware on May 1, 2019 and its corporate headquarters is located in New York, New York. Currently, the Company is devoting substantially all efforts and resources toward product research and development. The Company has incurred losses from operations and negative operating cash flows since its inception. There can be no assurance that its research and development programs will be successful, that products developed will obtain necessary regulatory approval, or that any approved product will be commercially viable. In addition, the Company operates in an environment of rapid technological change and is largely dependent on the services of its key employees, consultants, and advisors. The Company is subject to risks and uncertainties common to early-stage companies in the biotechnology industry including, but not limited to, uncertainty of product development and commercialization, lack of marketing and sales history, development by its competitors of new technological innovations, dependence on its key personnel, market acceptance of products, product liability, protection of proprietary technology, ability to raise additional financing, and compliance with government regulations. If the Company does not successfully commercialize any of its product candidates, it will be unable to generate recurring product revenue or achieve profitability. The Company’s potential product candidates that are in development require significant additional research and development efforts, including extensive preclinical and clinical testing and regulatory approval prior to commercialization. These efforts require significant amounts of additional capital, adequate personnel and infrastructure, and extensive compliance-reporting capabilities. Even if its product development efforts are successful, it is uncertain when, if ever, the Company will generate revenue from product sales. Liquidity and Going Concern In accordance with Accounting Standards Update No. 2014-15, Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern 205-40), • Since its inception, the Company has funded its operations primarily with outside capital (i.e., proceeds from the sale of preferred stock) and has incurred significant recurring losses, including net losses of $28.5 million and $13.1 million for the years ended December 31, 2022 and 2021, respectively. In addition, the Company had an accumulated deficit of $45.9 million as of December 31, 2022; • The Company expects to continue to incur significant recurring losses and rely on outside capital to fund its operations for the foreseeable future; and • The Company expects its available cash, cash equivalents and short-term investments on hand as of the issuance date will not be sufficient to fund its obligations as they become due for at least one year beyond the issuance date. While the Company is seeking to secure additional outside capital as of the issuance date, management can provide no assurance such capital will be secured or on terms that are acceptable to the Company. Similarly, as disclosed in Note 17, while the Company plans to consummate a reverse merger and concurrent private financing during the second half of fiscal year 2023, management can provide no assurance the reverse merger and concurrent private financing will be consummated on terms that are acceptable to the Company, if at all. In the event the Company is unable to secure additional outside capital and/or consummate the reverse merger and concurrent private financing, management will be required to seek other alternatives which may include, among others, a delay or termination of clinical trials or the development of its product candidates, temporary or permanent curtailment of the Company’s operations, a sale of assets, or other alternatives with strategic or financial partners. These uncertainties raise substantial doubt about the Company’s ability to continue as a going concern. The accompanying financial statements do not include any adjustments that might result from the outcome of these uncertainties. Accordingly, the financial statements have been prepared on a basis that assumes the Company will continue as a going concern and which contemplates the realization of assets and satisfaction of liabilities and commitments in the ordinary course of business. Merger and Exchange Ratio On May 2, 2023, the Company entered into a Merger Agreement with Magenta Therapeutics, Inc. (“Magenta”) and Dio Merger Sub, Inc. (“Merger Sub”). Pursuant to the Merger Agreement, among other matters, Merger Sub merged with and into the Company with the Company continuing as a wholly owned subsidiary of Magenta and the surviving corporation of the merger (“Merger”). Concurrently with the execution of the Merger Agreement, and in order to provide the Company with additional capital for its development programs prior to the closing of this Merger, certain new and existing investors purchased an aggregate of approximately On September 11, 2023, the Company completed its Merger with Magenta and Merger Sub. In connection with the completion of the Merger, the Company changed its name from “Dianthus Therapeutics, Inc.” to “Dianthus Therapeutics OpCo, Inc.,” Magenta changed its name to “Dianthus Therapeutics, Inc.” and the business conducted by Magenta became primarily the business conducted by the Company. At the effective time of the Merger, Magenta issued an aggregate of shares of its common stock to the Company’s stockholders (after giving effect to the 1-for-16 reverse stock split of Magenta common stock in connection with the Merger), based on the exchange ratio of approximately 0.2181 shares of Magenta common stock for each share of the Company’s common stock, including those shares of the Company’s common stock issued upon the conversion of the Company’s preferred stock and those shares of the Company’s common stock issued in the pre-closing financing (as defined above), resulting in 14,817,762 shares of the Company’s common stock being issued and outstanding following the effective time of the Merger. The Merger has been accounted for as a reverse recapitalization in accordance with generally accepted accounting principles in the United States of America (“U.S. GAAP”). Under this method of accounting, the Company is deemed to be the accounting acquirer for financial reporting purposes. This determination was based on the fact that, immediately following the Merger: (i) the Company’s stockholders own a substantial majority of the voting rights in the combined company; (ii) the Company’s largest stockholders retained the largest interest in the combined company; (iii) the Company designated a majority (six of eight) of the initial members of the board of directors of the combined company; and (iv) the Company’s executive management team became the management team of the combined company. Historical common share figures of the Company have been retroactively restated based on the exchange ratio of approximately . |
Summary of Significant Accounti
Summary of Significant Accounting Policies | 9 Months Ended | 12 Months Ended |
Sep. 30, 2023 | Dec. 31, 2022 | |
Summary of Significant Accounting Policies | 2. Summary of Significant Accounting Policies Basis of Presentation The accompanying unaudited condensed consolidated financial statements as of September 30, 2023 and for the nine months ended September 30, 2023 and 2022 have been prepared in conformity with U.S. GAAP, for interim financial information and pursuant to Article 10 of Regulation S-X period. The unaudited condensed consolidated balance sheet as of December 31, 2022 has been derived from the audited financial statements at that date but does not include all disclosures required by U.S. GAAP for complete financial statements. Because all of the disclosures required by U.S. GAAP for complete financial statements are not included herein, these unaudited condensed consolidated financial statements and the notes accompanying them should be read in conjunction with the Former Dianthus’ audited financial statements as of and for the years ended December 31, 2022 and 2021, included as Exhibit 99.5 of the Company’s Current Report on Form 8-K Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of expenses during the reporting period. Actual results may differ materially from those estimates. Management considers many factors in selecting appropriate financial accounting policies and controls, and in developing the estimates and assumptions that are used in the preparation of these financial statements. Management must apply significant judgment in this process. In addition, other factors may affect estimates including the following: expected business and operational changes, sensitivity and volatility associated with the assumptions used in developing estimates, and whether historical trends are expected to be representative of future trends. The estimation process often may yield a range of potentially reasonable estimates of the ultimate future outcomes, and management must select an amount that falls within that range of reasonable estimates. Significant estimates are used in the following areas, among others: the recognition of research and development expense, stock-based compensation expense and revenue recognition. Cash and Cash Equivalents All short-term, highly liquid investments with original maturities of 90 days or less are considered to be cash and cash equivalents. The carrying amounts reported in the unaudited condensed consolidated balance sheets for cash and cash equivalents are valued at cost, which approximates fair value. Concentration of Credit Risk Financial instruments that potentially subject the Company to concentrations of credit risk consist principally of cash, cash equivalents and short-term investments. The Company regularly maintains deposits in accredited financial institutions in excess of federally insured limits. The Company invests its excess cash primarily in money market funds, U.S. treasury securities and U.S. government agency securities in accordance with the Company’s investment policy. The Company’s investment policy defines allowable investments and establishes guidelines relating to credit quality, diversification, and maturities of its investments to preserve principal and maintain liquidity. The Company has not experienced any realized losses related to its cash, cash equivalents and short-term investments and management believes the Company is not exposed to significant risks of losses. As of September 30, 2023 and December 31, 2022, the Company held cash deposits at Silicon Valley Bank (“SVB”) in excess of government insured limits. On March 10, 2023, SVB was closed by the California Department of Financial Protection and Innovation, and the Federal Deposit Insurance Corporation was appointed as receiver. No losses were incurred by the Company on deposits that were held at SVB. Management believes that the Company is not currently exposed to significant credit risk as the vast majority of the Company’s deposits were either owned directly by the Company and held in custody at a third-party financial institution or, subsequent to March 10, 2023, have been transferred to a third-party financial institution. The Company does not currently have any other significant relationships with SVB. Short-term Investments Short-term investments consist of investments in U.S. treasury and U.S. government agency securities. Management of the Company determines the appropriate classification of the securities at the time they are acquired and evaluates the appropriateness of such classifications at each balance sheet date. The Company classifies its short-term investments as available-for-sale Investments – Debt and Equity Securities, Effective January 1, 2023, when the fair value is below the amortized cost of a marketable security, an estimate of expected credit losses is made. The credit-related impairment amount is recognized in the unaudited condensed consolidated statements of operations and comprehensive loss. Credit losses are recognized through the use of an allowance for credit losses account in the unaudited condensed consolidated balance sheet and subsequent improvements in expected credit losses are recognized as a reversal of an amount in the allowance account. If the Company has the intent to sell the security or it is more likely than not that the Company will be required to sell the security prior to recovery of its amortized cost basis, then the allowance for the credit loss is written-off Additional information regarding short-term investments is included in Note 4. Receivable from Related Party and Unbilled Receivable from Related Party The receivable from related party and unbilled receivable from related party results from option and license agreements with Zenas BioPharma Limited (“Zenas”), a related party. See Notes 13 and 16 for more information. The receivable represents amounts earned and billed to Zenas but not yet collected while unbilled receivable represents amounts earned but not yet billed to Zenas. The receivable and unbilled receivable are reported at net realizable value. The Company regularly evaluates the creditworthiness of Zenas and their financial condition and does not require collateral from Zenas. As of September 30, 2023 and December 31, 2022, no allowance for doubtful accounts was recorded as all accounts were considered collectible. Property and Equipment Property and equipment are recorded at cost. Depreciation is provided using the straight-line method over estimated useful lives of three years for computer equipment and five years for furniture and fixtures. Expenditures for major renewals and betterments that extend the useful lives are capitalized. Expenditures for normal maintenance and repairs are expensed as incurred. The cost of assets sold or abandoned, and the related accumulated depreciation are eliminated from the accounts and any gains or losses are recognized in the accompanying unaudited condensed consolidated statements of operations and comprehensive loss of the respective period. Leases Operating leases are accounted for in accordance with ASU 2016-02, Leases Right-of-use based on the present value of future lease payments over the lease term. As the Company’s leases do not provide an implicit rate, management used the Company’s incremental borrowing rate based on the information available at the lease commencement date in determining the present value of future lease payments. The right-of-use right-of-use The Company’s leases do not have significant rent escalation, holidays, concessions, material residual value guarantees, material restrictive covenants or contingent rent provisions. The Company’s leases include both lease (e.g., fixed payments including rent, taxes, and insurance costs) and non-lease non-lease Additional information and disclosures required under ASC 842 are included in Note 9. Restricted Cash In accordance with ASU 2016-18, Statement of Cash Flows (Topic 230): Restricted Cash Fair Value Measurements The Company calculates the fair value of assets and liabilities that qualify as financial instruments and includes additional information in the notes to the financial statements when the fair value is different than the carrying value of these financial instruments. The Company is required to disclose information on all assets and liabilities reported at fair value that enables an assessment of the inputs used in determining the reported fair values. ASC Topic 820, Fair Value Measurements and Disclosures Observable inputs are inputs that market participants would use in pricing the asset or liability based on market data obtained from sources independent of the Company. Unobservable inputs are inputs that reflect management’s assumptions about the inputs that market participants would use in pricing the asset or liability and are developed based on the best information available in the circumstances. The fair value hierarchy applies only to the valuation inputs used in determining the reported fair value of the investments and is not a measure of the investment credit quality. The three levels of the fair value hierarchy are described below: • Level 1—Quoted prices in active markets for identical assets or liabilities. • Level 2—Observable inputs other than quoted prices included in Level 1, such as quoted prices for similar assets and liabilities in active markets; quoted prices for identical or similar assets and liabilities in markets that are not active; or other inputs that are observable or can be corroborated by observable market data. • Level 3—Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets and liabilities. This includes certain pricing models, discounted cash flow methodologies and similar valuation techniques that use significant unobservable inputs. To the extent that a valuation is based on models or inputs that are less observable or unobservable in the market, the determination of fair value requires more judgment. Accordingly, the degree of judgment exercised by management in determining fair value is greatest for instruments categorized in Level 3. A financial instrument’s level within the fair value hierarchy is based on the lowest level of any input that is significant to the fair value measurement. Management has segregated all financial assets and liabilities that are measured at fair value on a recurring basis into the most appropriate level within the fair value hierarchy based on the inputs used to determine the fair value at the measurement date in the table below. The Company’s valuation techniques for its Level 2 financial assets included using quoted prices for similar assets in active markets and quoted prices for similar assets in markets that are not active. The estimated fair value of receivable from related party, unbilled receivable from related party, accounts payable and accrued expenses approximate their carrying amounts due to the relatively short maturity of these instruments. Additional information regarding fair value measurements is included in Note 7. Convertible Preferred Stock Convertible preferred stock is recorded at its original issuance price, less direct and incremental offering costs, as stipulated by its terms. The Company has applied the guidance in ASC 480-10-S99, Distinguishing Liabilities from Equity-Overall-SEC Segment Information Operating segments are defined as components of an entity for which separate financial information is available and that is regularly reviewed by the Chief Operating Decision Maker (“CODM”) in deciding how to allocate resources and in assessing performance. The Company’s CODM is its Chief Executive Officer (“CEO”). The Company operates as a single operating segment and has one reportable segment. License Revenue – Related Party To date, the Company’s only revenue has been attributable to an upfront payment and cost reimbursements under the Company’s license agreement with Zenas. The Company has not generated any revenue from product sales and does not expect to generate any revenue from product sales for the foreseeable future. The Company recognizes revenue pursuant to ASC 606, Revenue from Contracts with Customers (ii) identify the performance obligations in the contract; (iii) determine the transaction price; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when the performance obligation is satisfied. The Company evaluates the performance obligations promised in a contract that are based on goods and services that will be transferred to the customer and determine whether those obligations are both (i) capable of being distinct and (ii) distinct in the context of the contract. To the extent a contract includes multiple promised goods and services, the Company applies judgment to determine whether promised goods and services are both capable of being distinct and are distinct in the context of the contract. If these criteria are not met, the promised goods and services are accounted for as a combined performance obligation. Arrangements that include rights to additional goods or services that are exercisable at a customer’s discretion are generally considered options. The Company assesses if these options provide a material right to the customer and if so, they are considered performance obligations. The Company estimates the transaction price based on the amount expected to be received for transferring the promised goods or services in the contract. The consideration may include fixed consideration or variable consideration. At the inception of each arrangement that includes variable consideration, the Company evaluates the amount of potential transaction price and the likelihood that the transaction price will be received. Variable consideration is included in the transaction price if, in management’s judgment, it is probable that a significant future reversal of cumulative revenue under the contract will not occur. Any estimates, including the effect of the constraint on variable consideration, are evaluated at each reporting period for any changes. The Company then allocates the transaction price to each performance obligation and recognizes as revenue the amount of the transaction price that is allocated to the respective performance obligation when (or as) control is transferred to the customer and the performance obligation is satisfied. Amounts received prior to satisfying the revenue recognition criteria are recorded as deferred revenue in the Company’s balance sheets. If the related performance obligation is expected to be satisfied within the next twelve months this will be classified in current liabilities. Additional information and disclosures required under ASC 606 are included in Note 13. Research and Development Costs Research and development expenses are recorded as expense, as incurred. Research and development expenses consists of (i) costs to engage contractors who specialize in the development activities of the Company; (ii) external research and development costs incurred under arrangements with third parties, such as contract research organizations and consultants; and (iii) costs associated with preclinical activities and regulatory operations. The Company enters into consulting, research, and other agreements with commercial firms, researchers, and others for the provision of goods and services. Under such agreements, the Company may pay for services on a monthly, quarterly, project or other basis. Such arrangements are generally cancelable upon reasonable notice and payment of costs incurred. Costs are considered incurred based on an evaluation of the progress to completion of specific tasks under each contract using information and data provided by the service providers and vendors, whereas payments are dictated by the terms of each agreement. As such, depending on the timing of payment relative to the receipt of goods or services, management may record either prepaid expenses or accrued services. These costs consist of direct and indirect costs associated with specific projects, as well as fees paid to various entities that perform certain research on behalf of the Company. Patent costs Patent costs are expensed as incurred and recorded within general and administrative expenses. Income Taxes Income taxes are recorded in accordance with ASC 740, Income Taxes The Company accounts for uncertain tax positions in accordance with the provisions of ASC 740. When uncertain tax positions exist, the Company recognizes the tax benefit of tax positions to the extent that the benefit will more likely than not be realized. The determination as to whether the tax benefit will more likely than not be realized is based upon the technical merits of the tax position, as well as consideration of the available facts and circumstances. As of September 30, 2023 and December 31, 2022, the Company did not have any material uncertain tax positions. The Company recognizes interest and penalties related to uncertain tax positions, if any exist, in income tax expense. Stock-Based Compensation The Company accounts for stock-based compensation awards in accordance with ASC Topic 718, Compensation – Stock Compensation Prior to the Reverse Merger, management utilized valuation methodologies in accordance with the framework of the American Institute of Certified Public Accountants Technical Practice Aid, Valuation of Privately Held Company Equity Securities Issued as Compensation Due to a lack of company-specific historical and implied volatility data, management bases its estimate of expected volatility on the historical volatility of a representative group of companies with similar characteristics to the Company, including stage of product development and life science industry focus. Management believes the group selected has sufficiently similar economic and industry characteristics and includes companies that are most representative of the Company. Management uses the simplified method, as prescribed by the SEC Staff Accounting Bulletin No. 107, Share-Based Payment rates appropriate for the term of the awards. The dividend yield assumption is based on history and expectation of paying no dividends. Compensation expense related to stock-based awards is calculated on a straight-line basis by recognizing the grant date fair value, over the associated service period of the award, which is generally the vesting term. Additional information regarding share-based compensation is included in Note 12. Comprehensive Loss The only component of comprehensive loss other than net loss is change in unrealized losses related to available-for-sale Net Loss per Share Basic and diluted net loss per share attributable to common stockholders are calculated in conformity with the two-class two-class Diluted net loss per share of common stock includes the effect, if any, from the potential exercise or conversion of securities, such as convertible preferred stock, stock options and unvested restricted common stock, which would result in the issuance of incremental shares of common stock. For diluted net loss per share, the weighted-average number of shares of common stock is the same for basic net loss per share due to the fact that when a net loss exists, dilutive securities are not included in the calculation as the impact is anti-dilutive. For all periods presented, basic and diluted net loss per share were the same, as any additional share equivalents would be anti-dilutive. Additional information is included in Note 14. Recently Adopted Accounting Pronouncements On January 1, 2023, the Company adopted ASU No. 2016-13, Financial Instruments – Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments available-for-sale, | 2. Summary of Significant Accounting Policies Basis of Presentation The financial statements have been prepared in conformity with U.S. generally accepted accounting principles (“U.S. GAAP”). Any reference in these notes to applicable guidance is meant to refer to authoritative U.S. GAAP as found in the Accounting Standards Codification (“ASC”) and Accounting Standards Updates (“ASU”) of the Financial Accounting Standards Board (“FASB”). Segment Information Operating segments are defined as components of an entity for which separate financial information is available and that is regularly reviewed by the Chief Operating Decision Maker (“CODM”) in deciding how to allocate resources and in assessing performance. The Company’s CODM is its Chief Executive Officer (“CEO”). The Company operates as a single one Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of expenses during the reporting period. Actual results may differ materially from those estimates. Management considers many factors in selecting appropriate financial accounting policies and controls, and in developing the estimates and assumptions that are used in the preparation of these financial statements. Management must apply significant judgment in this process. In addition, other factors may affect estimates including the following: expected business and operational changes, sensitivity and volatility associated with the assumptions used in developing estimates, and whether historical trends are expected to be representative of future trends. The estimation process often may yield a range of potentially reasonable estimates of the ultimate future outcomes, and management must select an amount that falls within that range of reasonable estimates. Significant estimates are used in the following areas, among others: the recognition of research and development expense, stock-based compensation expense and revenue recognition. Cash and Cash Equivalents All short-term, Concentration of Credit Risk Financial instruments that potentially subject the Company to concentrations of credit risk consist principally of cash, cash equivalents and short-term investments. The Company regularly maintains deposits in accredited financial institutions in excess of federally insured limits. The Company invests its excess cash primarily in money market funds, U.S. treasury securities and U.S. government agency securities in accordance with the Company’s investment policy. The Company’s investment policy defines allowable investments and establishes guidelines relating to credit quality, diversification, and maturities of its investments to preserve principal and maintain liquidity. The Company has not experienced any realized losses related to its cash, cash equivalents and short-term investments and management believes the Company is not exposed to significant risks of losses. As of December 31, 2022, the Company held cash deposits at Silicon Valley Bank (“SVB”) in excess of government insured limits. On March 10, 2023, SVB was closed by the California Department of Financial Protection and Innovation, and the Federal Deposit Insurance Corporation was appointed as receiver. No losses were incurred by the Company on deposits that were held at SVB. Management believes that the Company is not currently exposed to significant credit risk as the vast majority of the Company’s deposits were either owned directly by the Company and held in custody at a third-party financial institution or, subsequent to March 10, 2023, have been transferred to a third-party financial institution. The Company does not currently have any other significant relationships with SVB. Short-term Investments Short-term investments consist of investments in U.S. treasury and U.S. government agency securities. Management of the Company determines the appropriate classification of the securities at the time they are acquired and evaluates the appropriateness of such classifications at each balance sheet date. The Company classifies its short-term investments as available-for-sale Investments—Debt and Equity Securities Receivable from Related Party and Unbilled Receivable from Related Party The receivable from related party and unbilled receivable from related party results from option and license agreements with Zenas BioPharma Limited (“Zenas”), a related party. See Notes 12 and 16 for more information. The receivable represents amounts earned and billed to Zenas but not yet collected while unbilled receivable represents amounts estimated to be earned but not yet billed to Zenas. The receivable and unbilled receivable are reported at net realizable value. Management of the Company regularly evaluates the creditworthiness of Zenas and their financial condition and does not require collateral from Zenas. As of December 31, 2022 and 2021, no allowance for doubtful accounts was recorded as all accounts were considered collectible. Property and Equipment Property and equipment are recorded at cost. Depreciation is provided using the straight-line method over estimated useful lives of three years for computer equipment and five years for furniture and fixtures. Expenditures for major renewals and betterments that extend the useful lives are capitalized. Expenditures for normal maintenance and repairs are expensed as incurred. The cost of assets sold or abandoned, and the related accumulated depreciation are eliminated from the accounts and any gains or losses are recognized in the accompanying statements of operations and comprehensive loss of the respective period. Leases Operating leases are accounted for in accordance with ASU 2016-02, Leases Right-of-use right-of-use right-of-use The Company’s leases do not have significant rent escalation, holidays, concessions, material residual value guarantees, material restrictive covenants or contingent rent provisions. The Company’s leases include both lease (e.g., fixed payments including rent, taxes, and insurance costs) and non-lease non-lease Additional information and disclosures required under ASC 842 are included in Note 8. Restricted Cash In accordance with ASU 2016-18, Statement of Cash Flows (Topic 230): Restricted Cash Classification of Convertible Preferred Stock Convertible preferred stock is recorded at its original issuance price, less direct and incremental offering costs, as stipulated by its terms. The Company has adopted the guidance in ASC 480-10-S99, Distinguishing Liabilities from Equity-Overall-SEC Effective January 1, 2021, the Company early adopted ASU 2020-06, Debt—Debt with Conversion and Other Options (Subtopic 470-20) License Revenue—Related Party To date, the Company’s only revenue has been attributable to an upfront payment and cost reimbursements under the Company’s license agreement with Zenas. The Company has not generated any revenue from product sales and does not expect to generate any revenue from product sales for the foreseeable future. The Company recognizes revenue pursuant to ASC 606, Revenue from Contracts with Customers goods or services, in an amount that reflects the consideration that the entity expects to receive in exchange for those goods or services. To determine revenue recognition for arrangements that an entity determines are within the scope of ASC 606, the entity performs the following five steps: (i) identify the contract with a customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when the performance obligation is satisfied. The Company evaluates the performance obligations promised in a contract that are based on goods and services that will be transferred to the customer and determine whether those obligations are both (i) capable of being distinct and (ii) distinct in the context of the contract. To the extent a contract includes multiple promised goods and services, the Company applies judgment to determine whether promised goods and services are both capable of being distinct and are distinct in the context of the contract. If these criteria are not met, the promised goods and services are accounted for as a combined performance obligation. Arrangements that include rights to additional goods or services that are exercisable at a customer’s discretion are generally considered options. The Company assesses if these options provide a material right to the customer and if so, they are considered performance obligations. The Company estimates the transaction price based on the amount expected to be received for transferring the promised goods or services in the contract. The consideration may include fixed consideration or variable consideration. At the inception of each arrangement that includes variable consideration, the Company evaluates the amount of potential transaction price and the likelihood that the transaction price will be received. Variable consideration is included in the transaction price if, in management’s judgment, it is probable that a significant future reversal of cumulative revenue under the contract will not occur. Any estimates, including the effect of the constraint on variable consideration, are evaluated at each reporting period for any changes. The Company then allocates the transaction price to each performance obligation and recognizes as revenue the amount of the transaction price that is allocated to the respective performance obligation when (or as) control is transferred to the customer and the performance obligation is satisfied. Amounts received prior to satisfying the revenue recognition criteria are recorded as deferred revenue in the Company’s balance sheets. If the related performance obligation is expected to be satisfied within the next twelve months this will be classified in current liabilities. Additional information and disclosures required under ASC 606 are included in Note 12. Research and Development Costs Research and development expenses are recorded as expense, as incurred. Research and development expenses consists of (i) costs to engage contractors who specialize in the development activities of the Company; (ii) external research and development costs incurred under arrangements with third parties, such as contract research organizations and consultants; and (iii) costs associated with preclinical activities and regulatory operations. The Company enters into consulting, research, and other agreements with commercial firms, researchers, and others for the provision of goods and services. Under such agreements, the Company may pay for services on a monthly, quarterly, project or other basis. Such arrangements are generally cancellable upon reasonable notice and payment of costs incurred. Costs are considered incurred based on an evaluation of the progress to completion of specific tasks under each contract using information and data provided by the service providers and vendors, whereas payments are dictated by the terms of each agreement. As such, depending on the timing of payment relative to the receipt of goods or services, management may record either prepaid expenses or accrued services. These costs consist of direct and indirect costs associated with specific projects, as well as fees paid to various entities that perform certain research on behalf of the Company. Patent costs Patent costs are expensed as incurred and recorded within general and administrative expenses. Income Taxes Income taxes are recorded in accordance with ASC 740, Income Taxes ( The Company accounts for uncertain tax positions in accordance with the provisions of ASC 740. When uncertain tax positions exist, the Company recognizes the tax benefit of tax positions to the extent that the benefit will more likely than not be realized. The determination as to whether the tax benefit will more likely than not be realized is based upon the technical merits of the tax position, as well as consideration of the available facts and circumstances. As of December 31, 2022 and 2021, the Company did not have any material uncertain tax positions. The Company recognizes interest and penalties related to uncertain tax positions, if any exist, in income tax expense. Stock-Based Compensation The Company accounts for stock-based compensation awards in accordance with ASC Topic 718, Compensation —Stock Compensation Management utilizes estimates and assumptions in determining the fair value of the Company’s common stock. Stock options were granted at exercise prices that represented the fair value of the Company’s common stock on the specific grant dates. Management utilized valuation methodologies in accordance with the framework of the American Institute of Certified Public Accountants Technical Practice Aid, Valuation of Privately Held Company Equity Securities Issued as Compensation Due to the lack of a historical public market for the trading of the Company’s common stock and a lack of company-specific historical and implied volatility data, management based its estimate of expected volatility on the historical volatility of a representative group of companies with similar characteristics to the Company, including stage of product development and life science industry focus. Management believes the group selected has sufficient similar economic and industry characteristics and includes companies that are most representative of the Company. Management used the simplified method, as prescribed by the SEC Staff Accounting Bulletin No. 107, Share-Based Payment Compensation expense related to stock-based awards is calculated on a straight-line basis by recognizing the grant date fair value, over the associated service period of the award, which is generally the vesting term. Comprehensive Loss The only component of comprehensive loss other than net loss is change in unrealized losses related to available-for-sale Net Loss per Share Basic net income (loss) per share attributable to common stockholders is computed by dividing the net income (loss) by the weighted average number of shares of common stock outstanding for the period. Diluted net income (loss) per share attributable to common stockholders is computed by dividing net income (loss) by the weighted average number of common shares outstanding for the period, including potential dilutive common shares. For periods in which the Company has reported net losses, diluted net loss per share attributable to common stockholders is the same as basic net loss per share attributable to common stockholders, since dilutive common shares are not assumed to have been issued if their impact is anti-dilutive. Additional information is included in Note 14. Recently Issued Accounting Pronouncements In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments—Credit Losses (Topic 326) No. 2019-10, |
Reverse Merger
Reverse Merger | 9 Months Ended |
Sep. 30, 2023 | |
Business Combination and Asset Acquisition [Abstract] | |
Reverse Merger | 3. Reverse Merger As described in Note 1, Merger Sub merged with and into Former Dianthus, with Former Dianthus surviving as a wholly owned subsidiary of the Company on September 11, 2023. The Reverse Merger was accounted for as a reverse asset acquisition accounted for as a reverse recapitalization in accordance with U.S. GAAP with Former Dianthus as the accounting acquirer of Magenta. At the effective time of the Reverse Merger, substantially all of the assets of Magenta consisted of cash and cash equivalents, marketable securities, as well as other nominal non-operating As part of the recapitalization, the Company obtained the assets and liabilities listed below: Cash and cash equivalents $ 69,738 Other current assets 2,473 Accrued liabilities (616 ) Net assets acquired $ 71,595 The Company incurred $0.5 million in stock-based compensation expense as a result of the acceleration of vesting of stock options and restricted share units for certain former employees of Magenta at the time of the Reverse Merger. Of this amount, $0.2 million was recorded in the research and development expenses line item and $0.3 million was recorded in the general and administrative expenses in the accompanying unaudited condensed consolidated statements of operations and comprehensive loss for the each of the three and nine months ended September 30, 2023. Additionally, the Company incurred transaction costs of $4.0 million, and this amount was recorded as a reduction to additional paid-in With respect to the CVRs issued in connection with the Reverse Merger, the Company believes that the achievement of the milestones outlined in the CVR Agreement are highly susceptible to factors outside the Company’s influence that are not expected to be resolved for a long period of time, if at all. In particular, these amounts are primarily influenced by the actions and judgments of third parties and the buyers of such assets and are based on the buyers of such assets progressing the in-process |
Short-Term Investments
Short-Term Investments | 9 Months Ended | 12 Months Ended |
Sep. 30, 2023 | Dec. 31, 2022 | |
Short-Term Investments [Abstract] | ||
Short-Term Investments | 4. Short-Term Investments The following table provides a summary of short-term investments: September 30, 2023 Amortized Gross Gross Fair Value Available-for-sale, U.S. treasury securities $ 25,656 $ 2 $ (1 ) $ 25,657 U.S. government agency securities 6,930 2 (1 ) 6,931 Total available-for-sale, $ 32,586 $ 4 $ (2 ) $ 32,588 December 31, 2022 Amortized Gross Gross Fair Available-for-sale, U.S. treasury securities $ 47,630 $ 3 $ (122 ) $ 47,511 U.S. government agency securities 12,656 — (42 ) 12,614 Total available-for-sale, $ 60,286 $ 3 $ (164 ) $ 60,125 | 3. Short-Term Investments The table below provides a summary of short-term investments (in thousands) as of December 31, 2022. There were no short-term investments as of December 31, 2021. December 31, 2022 Amortized Gross Gross Fair Available-for-sale, U.S. treasury securities $ 47,630 $ 3 $ (122 ) $ 47,511 U.S. government agency securities 12,656 — (42 ) 12,614 Total available-for-sale, $ 60,286 $ 3 $ (164 ) $ 60,125 As of December 31, 2022, the available-for-sale available-for-sale available-for-sale |
Prepaid Expenses and Other Curr
Prepaid Expenses and Other Current Assets | 9 Months Ended | 12 Months Ended |
Sep. 30, 2023 | Dec. 31, 2022 | |
Prepaid Expense and Other Assets, Current [Abstract] | ||
Prepaid Expenses and Other Current Assets | 5. Prepaid Expenses and Other Current Assets The following table provides a summary of prepaid expenses and other current assets: September 30, December 31, Prepaid materials, supplies and research and development services $ 337 $ 820 Prepaid subscriptions, software and other administrative services 475 53 Prepaid insurance 20 32 Prepaid expenses and other current assets $ 832 $ 905 | 4. Prepaid Expenses and Other Current Assets The following table provides a summary of prepaid expenses and other current assets (in thousands): December 31, 2022 2021 Prepaid materials, supplies and services $ 820 $ 243 Prepaid insurance 32 21 Other 53 10 Prepaid expenses and other current assets $ 905 $ 274 |
Property and Equipment
Property and Equipment | 9 Months Ended | 12 Months Ended |
Sep. 30, 2023 | Dec. 31, 2022 | |
Property, Plant and Equipment [Abstract] | ||
Property and Equipment | 6. Property and Equipment The following table provides a summary of property and equipment: September 30, December 31, Computer equipment $ 231 $ 131 Furniture and fixtures 41 41 Subtotal 272 172 Less: accumulated depreciation (77 ) (30 ) Property and equipment, net $ 195 $ 142 Depreciation expense was $19 thousand and $47 thousand in the three and nine months ended September 30, 2023, respectively, and $6 thousand and $19 thousand in the three and nine months ended September 30, 2022, respectively. | 5. Property and Equipment The following table provides a summary of property and equipment (in thousands): December 31, 2022 2021 Computer equipment $ 131 $ — Furniture and fixtures 41 — Construction-in-process — 33 Subtotal 172 33 Less: accumulated depreciation (30 ) — Property and equipment, net $ 142 $ 33 Depreciation expense was $30 thousand for the year ended December 31, 2022. No depreciation expense was recognized during the year ended December 31, 2021 as the assets had not yet been placed in service as of that date |
Fair Value of Financial Instrum
Fair Value of Financial Instruments | 9 Months Ended | 12 Months Ended |
Sep. 30, 2023 | Dec. 31, 2022 | |
Fair Value Disclosures [Abstract] | ||
Fair Value of Financial Instruments | 7. Fair Value of Financial Instruments The following table provides a summary of financial assets measured at fair value on a recurring basis: Description Fair Value at Level 1 Level 2 Level 3 Recurring Assets: Cash equivalents: Money market funds $ 154,549 $ 154,549 $ — $ — Short-term investments: U.S. treasury securities 25,657 25,657 — — U.S. government agency securities 6,931 — 6,931 — Total assets measured at fair value $ 187,137 $ 180,206 $ 6,931 $ — Description Fair Value at Level 1 Level 2 Level 3 Recurring Assets: Cash equivalents: Money market funds $ 11,846 $ 11,846 $ — $ — U.S. government agency securities 1,999 — 1,999 — Short-term investments: U.S. treasury securities 20,775 20,775 — — U.S. government agency securities 39,350 26,736 12,614 — Total assets measured at fair value $ 73,970 $ 59,357 $ 14,613 $ — There have been no transfers between levels for the nine months ended September 30, 2023 or the year ended December 31, 2022. | 6. Fair Value of Financial Instruments Management calculates the fair value of assets and liabilities that qualify as financial instruments and includes additional information in the notes to the financial statements when the fair value is different than the carrying value of these financial instruments. The estimated fair value of accounts receivable, accounts payable and accrued expenses approximate their carrying amounts due to the relatively short maturity of these instruments. The Company is required to disclose information on all assets and liabilities reported at fair value that enables an assessment of the inputs used in determining the reported fair values. ASC Topic 820, Fair Value Measurements and Disclosures Observable inputs are inputs that market participants would use in pricing the asset or liability based on market data obtained from sources independent of the Company. Unobservable inputs are inputs that reflect management’s assumptions about the inputs that market participants would use in pricing the asset or liability and are developed based on the best information available in the circumstances. The fair value hierarchy applies only to the valuation inputs used in determining the reported fair value of the investments and is not a measure of the investment credit quality. The three levels of the fair value hierarchy are described below: • Level 1—Quoted prices in active markets for identical assets or liabilities. • Level 2—Observable inputs other than quoted prices included in Level 1, such as quoted prices for similar assets and liabilities in active markets; quoted prices for identical or similar assets and liabilities in markets that are not active; or other inputs that are observable or can be corroborated by observable market data. • Level 3—Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets and liabilities. This includes certain pricing models, discounted cash flow methodologies and similar valuation techniques that use significant unobservable inputs. To the extent that a valuation is based on models or inputs that are less observable or unobservable in the market, the determination of fair value requires more judgment. Accordingly, the degree of judgment exercised by management in determining fair value is greatest for instruments categorized in Level 3. A financial instrument’s level within the fair value hierarchy is based on the lowest level of any input that is significant to the fair value measurement. Management has segregated all financial assets and liabilities that are measured at fair value on a recurring basis into the most appropriate level within the fair value hierarchy based on the inputs used to determine the fair value at the measurement date in the table below. The Company’s valuation techniques for its Level 2 financial assets included using quoted prices for similar assets in active markets and quoted prices for similar assets in markets that are not active. The following table provides a summary of financial assets measured at fair value on a recurring basis (in thousands): Description Fair Value at Level 1 Level 2 Level 3 Recurring Assets: Cash equivalents: Money market fund $ 11,846 $ 11,846 $ — $ — U.S. government agency securities 1,999 — 1,999 — Short-term investments: U.S. treasury securities 20,775 20,775 — — U.S. government agency securities 39,350 26,736 12,614 — Total assets measured at fair value $ 73,970 $ 59,357 $ 14,613 $ — Description Fair Value at Level 1 Level 2 Level 3 Recurring Assets: Cash equivalents: Money market fund $ 7,675 $ 7,675 $ — $ — Total assets measured at fair value $ 7,675 $ 7,675 $ — $ — |
Accrued Expenses
Accrued Expenses | 9 Months Ended | 12 Months Ended |
Sep. 30, 2023 | Dec. 31, 2022 | |
Accrued Expenses | 8. Accrued Expenses The following table provides a summary of accrued expenses: September 30, December 31, Accrued external research and development $ 1,001 $ 4,329 Accrued compensation 4,429 2,084 Accrued issuance costs in connection with pre-closing 4,200 — Accrued transaction costs related to reverse recapitalization 419 — Accrued professional fees 667 162 Other accrued expenses 481 33 Accrued expenses $ 11,197 $ 6,608 | 7. Accrued Expenses The following table provides a summary of accrued expenses (in thousands): December 31, 2022 2021 Accrued external research and development $ 4,329 $ 3,560 Accrued compensation 2,084 207 Accrued professional fees and other 195 226 Accrued expenses $ 6,608 $ 3,993 |
Leases
Leases | 9 Months Ended | 12 Months Ended |
Sep. 30, 2023 | Dec. 31, 2022 | |
Leases [Abstract] | ||
Leases | 9. Leases The Company leases space under operating leases for administrative offices in New York, New York, and Waltham, Massachusetts and wet laboratory space in Watertown, Massachusetts. The Company also leased office space under operating leases, which had a non-cancelable right-of-use The following table provides a summary of the components of lease costs and rent: Three Months Nine Months 2023 2022 2023 2022 Operating lease cost $ 88 $ 66 $ 263 $ 110 Variable lease cost 7 1 20 4 Short-term lease cost — 6 — 34 Total operating lease costs $ 95 $ 73 $ 283 $ 148 The Company recorded operating lease costs of $95 thousand and $283 thousand within the general and administrative expenses line item in the unaudited condensed consolidated statements of operations and comprehensive loss for the three and nine months ended September 30, 2023, respectively. The Company recorded operating lease costs of $73 thousand and $148 thousand within the general and administrative expenses line item in the unaudited condensed consolidated statements of operations and comprehensive loss for the three and nine months ended September 30, 2022, respectively. Maturities of operating lease liabilities, which do not include short-term leases, as of September 30, 2023, are as follows: 2023 (remaining 3 months) $ 102 2024 417 2025 222 Total undiscounted operating lease payments 741 Less: imputed interest (71 ) Present value of operating lease liabilities $ 670 Balance sheet classification: Current portion of lease liabilities $ 413 Long-term lease liabilities 257 Total operating lease liabilities $ 670 The weighted-average remaining term of operating leases was 22 months and the weighted-average discount rate used to measure the present value of operating lease liabilities was 10.6% as of September 30, 2023. | 8. Leases The Company leases space under operating leases for administrative offices in New York, New York and Waltham, Massachusetts. The Company also leased office space under operating leases, which had a non-cancelable right-of-use The following table provides a summary of the components of lease costs and rent (in thousands): Years Ended 2022 2021 Operating lease cost $ 198 $ — Variable lease cost 4 — Short-term lease cost 34 17 Total operating lease costs $ 236 $ 17 The Company records the operating lease costs within the general and administrative expenses line item in the statements of operations and comprehensive loss during the years ended December 31, 2022 and 2021. Maturities of operating lease liabilities, which do not include short-term leases, as of December 31, 2022, are as follows (in thousands): 2023 $ 351 2024 365 2025 188 Total undiscounted operating lease payments 904 Less: imputed interest (116 ) Present value of operating lease liabilities $ 788 Balance sheet classification: Current portion of lease liabilities $ 350 Long-term lease liabilities 438 Total operating lease liabilities $ 788 The weighted-average remaining term of operating leases was 30 months and the weighted-average discount rate used to measure the present value of operating lease liabilities was 10.3% as of December 31, 2022. |
Convertible Preferred Stock
Convertible Preferred Stock | 12 Months Ended |
Dec. 31, 2022 | |
Temporary Equity Disclosure [Abstract] | |
Convertible Preferred Stock | 9. Convertible Preferred Stock As of December 31, 2022 and 2021, the Company was authorized to issue 33,336,283 and 10,329,266 shares of preferred stock, respectively, par value $0.0001 per share. Series Seed 1: 1 On December 1, 2020, the Company executed an amendment to the Series Seed 1 providing for a third closing which was completed on the same date. In connection with this amendment, the Company issued 3,000,000 shares of Series Seed 1 Convertible Preferred Stock, at a price of $1.00 per share. Gross proceeds from the third closing issuance were $3.0 million. This amendment provided for a potential fourth closing, which did not occur. Series Seed 2: Series A: The Series Seed 1, Series Seed 2 and Series A preferred stock are collectively referred to as “Preferred Stock” and have the following characteristics: Voting Each holder of outstanding shares of Preferred Stock shall be entitled to cast the number of votes equal to the number of whole shares of Common Stock into which the shares of Preferred Stock held by such holder are convertible as of the record date for determining stockholders entitled to vote on such matter. Dividends The holders of Preferred Stock are entitled to receive dividends, as specified in the Company’s Amended and Restated Certificate of Incorporation (the “Certificate of Incorporation”), if and when declared by the Company’s Board of Directors. The Series Seed preferred stockholders are entitled to receive dividends at a rate of $0.06 per annum per share. The Series Seed 2 preferred stockholders are entitled to receive dividends at a rate of $0.235 per annum per share. The Series A preferred stockholders are entitled to receive dividends at a rate of $0.2608 per annum per share. Such dividends are not cumulative. Since the Company’s inception, no dividends have been declared or paid to the holders of Preferred Stock. Liquidation, dissolution or winding up In the event of any voluntary or involuntary liquidation, dissolution or winding up of the Company or deemed liquidation event (as defined in the Certificate of Incorporation), the holders of the Preferred Stock have first priority to be paid an amount equal to the greater of (i) the respective Preferred Stock issuance price plus dividends declared but unpaid or (ii) such amounts that would have been owed to the holders of Preferred Stock if the Preferred Stock shares had been converted to common stock prior to the liquidation event. Following payment to the holders of Preferred Stock, all remaining assets of the Company will be distributed to the common stock shareholders on a pro rata basis. Conversion Each share of Preferred Stock is convertible, at the option of the holder thereof, at any time and from time to time, and without the payment of additional consideration by the holder thereof, into such number of fully paid and non-assessable Mandatory conversion shall occur upon either (a) the closing of the sale of shares of common stock to the public at a price of at least $8.6930 per share (subject to appropriate adjustment as defined in the Certificate of Incorporation), in a firm-commitment underwritten public offering pursuant to an effective registration statement under the Securities Act of 1933, as amended, resulting in at least $40.0 million of gross proceeds to the Company and in connection with such offering the Common Stock is listed for trading on the Nasdaq Stock Market’s National Market, the New York Stock Exchange or another exchange or marketplace approved the Company’s Board of Directors, or (b) the date and time, or the occurrence of an event, specified by vote or written consent of the Requisite Holders (as defined in the Certificate of Incorporation). Redemption Shares of Preferred Stock are not redeemable at the election of the holder thereof. Any shares of Preferred Stock that are redeemed or otherwise acquired by the Company shall be automatically and immediately cancelled and retired (as defined in the Certificate of Incorporation). Adjustment of conversion price upon issuance of additional shares of common stock In the event the Company issues additional shares of common stock without consideration or consideration less than the Preferred Stock conversion price in effect immediately prior to such issuance, then the Preferred Stock conversion price shall be adjusted in accordance with the adjustment formula (as set forth in the Certificate of Incorporation). |
Common Stock
Common Stock | 9 Months Ended | 12 Months Ended |
Sep. 30, 2023 | Dec. 31, 2022 | |
Equity [Abstract] | ||
Common Stock | 10. Common Stock At the effective time of the Reverse Merger on September 11, 2023, the Company issued an aggregate of 11,021,248 shares of Company common stock to the Former Dianthus stockholders, based on the exchange ratio of approximately 0.2181 shares of Company common stock for each share of Former Dianthus common stock, including those shares of Former Dianthus common stock issued upon the conversion of Former Dianthus preferred stock and those shares of the Former Dianthus common stock issued in the pre-closing As of September 30, 2023 and December 31, 2022, the Company was authorized to issue up to 150,000,000 shares of $0.001 par value of Company common stock and 8,722,279 shares of $0.0001 par value of Company common stock, respectively. In the Company’s Form 10-Q filing for the period ended September 30, 2023, the Company incorrectly reported that it was authorized to issue up to 40,000,000 shares of $0.0001 par value of Company common stock as of December 31, 2022. As of September 30, 2023 and December 31, 2022, the Company had issued and outstanding shares of 14,817,762 and 875,279, respectively. Each share of Company common stock entitles the holder to one vote on all matters submitted to a vote of the Company’s stockholders. Common stockholders are entitled to receive dividends, as may be declared by the Company’s board of directors, if any. No dividends have been declared or paid by the Company through September 30, 2023. The Company had the following shares of Company common stock reserved for future issuance as of September 30, 2023 and December 31, 2022: As of As of Conversion of convertible preferred stock — 7,269,183 Issuance of common stock upon exercise of stock options 1,772,179 1,273,454 Equity awards available for grant under stock awards 767,454 414,679 Shares available for issuance under the Employee Stock Purchase Plan 37,078 — Issuance of common stock upon exercise of warrants 214,997 4,677 Total common stock reserved for future issuance 2,791,708 8,961,993 | 10. Stockholders’ Equity/(Deficit) Common Stock As of December 31, 2022 and 2021, the Company was authorized to issue 8,722,279 and 3,706,968 shares of common stock, respectively, with a par value of $0.0001 per share. In January 2023, the Company amended its Certificate of Incorporation to increase the authorized common stock to 9,837,322 shares. The Common Stock has the following characteristics: Voting The holders of common stock are entitled to one vote for each share of common stock held at all meetings of stockholders (and written actions in lieu of meetings); provided, however, that, except as otherwise required by law, holders of common stock, as such, shall not be entitled to vote on any amendment to the Certificate of Incorporation that relates solely to the terms of one or more outstanding series of preferred stock if the holders of such affected series are entitled, either separately or together with the holders of one or more other such series, to vote thereon pursuant to the Certificate of Incorporation or pursuant to the Delaware General Corporation Law. Dividends The holders of common stock are entitled to receive dividends, if and when declared by the Company’s Board of Directors. Since the Company’s inception, no dividends have been declared or paid to the holders of common stock. Liquidation, dissolution or winding up In the event of any voluntary or involuntary liquidation, dissolution, or winding-up |
Preferred Stock and Convertible
Preferred Stock and Convertible Preferred Stock | 9 Months Ended |
Sep. 30, 2023 | |
Stockholders' Equity Note [Abstract] | |
Preferred Stock and Convertible Preferred Stock | 11. Preferred Stock and Convertible Preferred Stock Preferred Stock As of September 30, 2023, the Company was authorized to issue up to 10,000,000 shares of preferred stock at a par value of $0.001. As of September 30, 2023, no shares of preferred stock were issued and outstanding. Convertible Preferred Stock On September 11, 2023, the Company completed the Reverse Merger with Former Dianthus in accordance with the Merger Agreement. Under the terms of the Merger Agreement, immediately prior to the effective time of the Reverse Merger, each share of Former Dianthus convertible preferred stock was converted into a share of Former Dianthus common stock. At closing of the Reverse Merger, the Company issued an aggregate of 7,269,183 shares of its common stock to Former Dianthus convertible preferred stockholders, based on the exchange ratio of approximately 0.2181 shares of Company common stock for each share of Former Dianthus common stock outstanding immediately prior to the Reverse Merger. The authorized, issued and outstanding shares of the convertible preferred stock and liquidation preferences of Former Dianthus as of December 31, 2022 were as follows: Issued Authorized Shares Per Share Aggregate Proceeds Series Seed 1 Convertible Preferred Stock July 2019, April 2020 and December 2020 6,500,000 6,500,000 $ 1.000 $ 6,500 $ 6,436 Series Seed 2 Convertible Preferred Stock May 2021 3,829,266 3,829,265 $ 3.9172 15,000 14,912 Series A Convertible Preferred Stock April 2022 23,007,017 23,007,017 $ 4.3465 100,000 96,676 Total Convertible Preferred Stock 33,336,283 33,336,282 $ 121,500 $ 118,024 |
Stock-Based Compensation
Stock-Based Compensation | 9 Months Ended | 12 Months Ended |
Sep. 30, 2023 | Dec. 31, 2022 | |
Share-Based Payment Arrangement [Abstract] | ||
Stock-Based Compensation | 12. Stock-Based Compensation 2018 Stock Option and Incentive Plan The Company grants stock-based awards under the Amended and Restated Dianthus Therapeutics, Inc. Stock Option and Incentive Plan (the “2018 Incentive Plan”), which originally became effective on June 19, 2018 as the Magenta Therapeutics, Inc. 2018 Stock Option and Incentive Plan and was amended and restated in September 2023 and renamed the Amended and Restated Dianthus Therapeutics, Inc. Stock Option and Incentive Plan. The 2018 Incentive Plan provides for the grant of incentive stock options, nonqualified stock options, stock appreciation rights, restricted stock awards, restricted stock units, unrestricted stock awards, cash-based awards, and dividend equivalent rights. In connection with the Reverse Merger, the 2018 Incentive Plan also provides for the assumption of shares remaining available for delivery under the 2019 Stock Plan (as defined below), and such shares will be available for the granting of awards under the 2018 Incentive Plan in accordance with applicable stock exchange requirements. The Company also has outstanding stock options under the Magenta Therapeutics, Inc. 2016 Stock Option and Grant Plan, as amended (the “2016 Plan”), but is no longer granting awards under the 2016 Plan. Following the Reverse Stock Split effected on September 11, 2023, and after adjustments for the assumption of shares available under the 2019 Stock Plan, the number of shares reserved for issuance under the 2018 Incentive Plan is equal to 1,039,611 shares of the Company’s common stock. The 2018 Incentive Plan provides that the number of shares reserved and available for issuance under the 2018 Incentive Plan will automatically increase each January 1 beginning with January 1, 2024 by 4% of the outstanding number of shares of the Company’s common stock on the immediately preceding December 31 or such lesser number of shares as determined by the Company’s board of directors or compensation committee of the board of directors. This number is subject to adjustment in the event of a stock split, stock dividend or other change in capitalization. Shares of common stock underlying any awards under the 2018 Incentive Plan and the 2016 Plan that are forfeited, cancelled, held back upon exercise or settlement of an award to satisfy the exercise price or tax withholding, reacquired by the Company prior to vesting, satisfied without any issuance of stock, expire or are otherwise terminated (other than by exercise) will be available for future awards under the 2018 Incentive Plan. As of September 30, 2023, 767,454 shares of the Company’s common stock were available for issuance under the 2018 Incentive Plan. The 2018 Incentive Plan is administered by either the board of directors or the compensation committee of the board of directors. The exercise prices, vesting and other restrictions are determined at the discretion of the administrator, except that the term of stock options and stock appreciation rights may not be greater than ten years (or five years for certain incentive stock options). Awards typically vest over 12 months to four years. The exercise price for stock options granted may not be less than the fair value of common stock as of the date of grant (or 110% of the fair value of common stock for certain incentive stock options). The fair value of common stock is based on quoted market prices. 2019 Stock Plan In July 2019, Former Dianthus’ Board of Directors adopted, and the Former Dianthus’ stockholders approved, the Dianthus Therapeutics, Inc. 2019 Stock Plan (the “2019 Stock Plan”). In connection with the Reverse Merger, the Company assumed options to purchase shares of Former Dianthus’s common stock that were outstanding under the 2019 Stock Plan immediately prior to the Reverse Merger and such options were converted into options to purchase 1,486,408 shares of Company’s common stock (the “Assumed Options”). No further awards will be made under the 2019 Stock Plan; however, the Assumed Options will remain outstanding under the 2019 Stock Plan in accordance with their terms, as adjusted to reflect the Reverse Merger. 2019 Employee Stock Purchase Plan Employees may elect to participate in the Magenta Therapeutics, Inc. 2019 Employee Stock Purchase Plan (the “ESPP”). The purchase price of common stock under the ESPP is equal to 85% of the lower of the fair market value of the common stock on the offering date or the exercise date. The six-month The ESPP provides that the number of shares reserved and available for issuance under the ESPP will automatically increase each January 1 through January 1, 2029, by the lesser of (i) 1% of the number of shares issued and outstanding on the immediately preceding December 31, (ii) 1,000,000 shares and (iii) such number of shares as determined by the Company’s board of directors or its appointed administrator. The number of shares reserved for issuance under the ESPP did not increase on January 1, 2023. Stock Options The following table summarizes stock option activity for the nine months ended September 30, 2023: Number of Weighted Weighted Aggregate (in years) Balance at January 1, 2023 529,773 $ 94.59 8.2 $ — Assumption of options in connection with the Reverse Merger 1,273,454 7.95 177 Options granted, fair value of $10.86 per share 440,041 12.31 159 Options exercised (2,798 ) 1.66 46 Options forfeited (468,291 ) 68.14 397 Balance at September 30, 2023 1,772,179 $ 19.04 8.0 $ 7,763 Exercisable options at September 30, 2023 699,237 $ 33.25 6.5 $ 2,949 Unvested options at September 30, 2023 1,072,942 $ 9.78 8.9 $ 4,814 The aggregate intrinsic value of options is calculated as the difference between the exercise price of the options and the fair value of the common stock for those options that had exercise prices lower than the fair value of the common stock. The weighted average grant-date fair value per share of stock options granted during the nine months ended September 30, 2023 was $10.86 per share. The table below summarizes the assumptions used to determine the grant-date fair value of stock options issued, presented on a weighted average basis during the nine months ended September 30, 2023 and 2022. Nine Months Nine Months Risk-free interest rate 3.9 % 3.1 % Expected term (in years) 6.0 5.9 Expected volatility 86.4 % 87.3 % Expected dividend yield 0.0 % 0.0 % Restricted Stock Units The following table summarizes restricted stock unit activity for the nine months ended September 30, 2023: Number of Weighted average Balance at January 1, 2023 16,084 $ 70.09 Restricted share units granted 7,696 8.80 Restricted share units vested (6,495 ) 68.96 Restricted share units forfeited (17,285 ) 43.22 Balance at September 30, 2023 — $ — Restricted Stock In April 2020, Former Dianthus executed a restricted stock award agreement with a consultant to purchase 3,052 shares of common stock at an exercise price of $0.14 per share. The restricted stock award vests over a four-year requisite service period, with 25% vesting on the first anniversary of the vesting commencement date and 2.0833% per month thereafter. The agreement contains restrictions on the ability to sell, assign or pledge the shares awarded. The restricted stock agreement contains a right of repurchase whereby, at the election of the Company, the Company may purchase back all unvested stock should the relationship between the recipient and the Company cease. The fair value of the restricted stock award on the date of the award was $0.14 per share. Former Dianthus has not issued any restricted stock since April 2020. As of September 30, 2023, a total of 2,989 shares of restricted common stock were vested and 63 shares remained unvested. As of September 30, 2023, the unrecognized stock-based compensation expense for the restricted award was immaterial. Stock Warrants In April 2021, Former Dianthus issued 4,677 warrants for the purchase of common stock at an exercise price of $1.65 per share. The warrants vested on July 30, 2023 and have a grant date fair value of $1.16 per warrant. Former Dianthus has not issued any warrants since April 2021. As of September 30, 2023, the warrants have a weighted average remaining contractual term of 7.6 years. Stock-based Compensation Expense The following table provides a summary of stock-based compensation expense related to stock options, restricted stock units, restricted stock, and warrants: Three Months Nine Months Ended 2023 2022 2023 2022 Research and development $ 379 $ 144 $ 711 $ 256 General and administrative 800 517 1,463 749 Total stock-based compensation expense $ 1,179 $ 661 $ 2,174 $ 1,005 As of September 30, 2023, there was $7.8 million of total unrecognized compensation cost related to granted stock options. The Company expects to recognize that cost over a remaining weighted-average period of 2.6 years. | 11. Stock-Based Compensation In July 2019, the Company’s Board of Directors adopted, and the stockholders approved, the Dianthus Therapeutics, Inc. 2019 Stock Plan (the “2019 Plan”). As of December 31, 2022, there were 1,691,208 shares of common stock reserved under the 2019 Plan for issuance to officers, employees, consultants, and directors of the Company. The 2019 Plan is administered by the Compensation Committee of the Company’s Board of Directors. As of December 31, 2022, the Company had issued 1,273,454 awards from the 2019 Plan and had 417,755 shares available for future grant. Shares that are expired, terminated, surrendered, or canceled under the 2019 Plan without having been fully exercised will be available for future awards. Stock Options The exercise price for stock options is determined at the discretion of the Compensation Committee of the Company’s Board of Directors. All stock options granted to any person possessing less than 10% of the total combined consolidated voting power of all classes of stock may not have an exercise price of less than 100% of the fair market value of the common stock on the grant date. All stock options granted to any person possessing more than 10% of the total combined consolidated voting power of all classes of stock may not have an exercise price of less than 110% of the fair market value of the common stock on the grant date. The option term may not be greater than ten years from the date of the grant. Stock options granted to persons possessing more than 10% of the total combined consolidated voting power of all classes of stock may not have an option term of greater than five years from the date of the grant. The vesting period for equity-based awards is determined at the discretion of the Compensation Committee of the Company’s Board of Directors, which is generally four years. For awards granted to employees and non-employees • 25% of the option vests on the first anniversary of the grant date and the remaining stock vest equally each month for three years thereafter, or • Equal vesting on a monthly basis, on the last day of the month following the vesting commencement date. The following table summarizes the assumptions used to determine the grant-date fair value of stock options granted, presented on a weighted average basis: Years Ended December 31, 2022 2021 Risk-free interest rate 3.08 % 1.20 % Expected term (in years) 5.9 6.1 Expected volatility 87.28 % 87.67 % Expected dividend yield 0 % 0 % The following table summarizes stock option activity: Number of Weighted Weighted Aggregate (in years) (in thousands) Balance at January 1, 2021 — $ — $ — Granted, fair value of $4.31 per share 248,603 5.92 Balance at December 31, 2021 248,603 5.92 9.7 194 Granted, fair value of $6.24 per share 1,031,567 8.44 Forfeited (6,716 ) 7.55 Balance at December 31, 2022 1,273,454 $ 7.95 9.3 $ 621 Exercisable options at December 31, 2022 181,171 $ 7.18 9.1 $ 229 Unvested options at December 31, 2022 1,092,283 $ 8.08 9.4 $ 392 The aggregate intrinsic value of options is calculated as the difference between the exercise price of the options and the fair value of the common stock for those options that had exercise prices lower than the fair value of the common stock. The weighted average grant-date fair value per share of stock options granted during the years ended December 31, 2022 and 2021 was $6.24 and $4.31, respectively. Restricted Stock In April 2020, the Company executed a restricted stock award agreement with a consultant to purchase 3,052 shares of common stock at an exercise price of $0.14 per share. The restricted stock award vests over a four-year requisite service period, with 25% vesting on the first anniversary of the vesting commencement date and 2.0833% per month thereafter. The agreement contains restrictions on the ability to sell, assign or pledge the shares awarded. The restricted stock agreement contains a right of repurchase whereby, at the election of the Company, the Company may purchase back all unvested stock should the relationship between the recipient and the Company cease. The fair value of the Company’s common stock on the date of the award was $0.14 per share. The Company did not issue any restricted stock during the years ended December 31, 2022 and 2021. As of December 31, 2022, a total of approximately 2,417 shares of restricted common stock were vested and approximately 635 shares remained unvested. As of December 31, 2022, the unrecognized stock-based compensation expense for the restricted award was immaterial. Stock Warrants In April 2021, the Company issued 4,677 warrants for the purchase of common stock at an exercise price of $1.65 per share. The warrants vest over a four-year period on a straight-line basis and have a grant date fair value of $1.16 per warrant. The weighted average assumptions used to determine the fair value of the warrants were as follows: Year Ended Risk-free interest rate 1.14 % Expected term (in years) 6.1 Expected volatility 82.80 % Expected dividend yield 0 % The Company did not issue any warrants during the year ended December 31, 2022. As of December 31, 2022, the warrants have a weighted average remaining contractual term of 8.3 years and a remaining weighted average vesting period of 7 months. Stock-based compensation expense The following table provides a summary of stock-based compensation expense related to stock options, restricted stock, and warrants (in thousands): Years Ended 2022 2021 Research and development $ 416 $ 19 General and administrative 1,102 44 Total stock-based compensation expense $ 1,518 $ 63 As of December 31, 2022, there was $5.9 million of total unrecognized compensation cost related to stock options granted under the 2019 Plan. The Company expects to recognize that cost over a remaining weighted-average period of 3.2 years. |
License Revenue - Related Party
License Revenue - Related Party | 9 Months Ended | 12 Months Ended |
Sep. 30, 2023 | Dec. 31, 2022 | |
Related Party Transactions [Abstract] | ||
License Revenue - Related Party | 13. License Revenue – Related Party In September 2020, the Company entered into an Option Agreement with Zenas (“Zenas Option”), a related party (See Note 16). Through the Zenas Option, the Company provided Zenas an option to enter into an exclusive license agreement for the development and commercialization of products arising from its research of monoclonal antibody antagonists targeting certain specific complement proteins. In September 2021, the Company notified Zenas that it had elected the first antibody sequence as a clinical candidate. In October 2021, Zenas notified the Company that it was exercising its option for such clinical candidate. The Zenas Option provided that upon the exercise of the option, the Company would negotiate in good faith a license agreement with Zenas pursuant to which it would grant Zenas the exclusive license with respect to the antibody sequences for the Zenas Territory, which includes People’s Republic of China, including Hong Kong, Macau, and Taiwan. In accordance with Zenas Option, within 60 days following the execution of a license agreement, Zenas agreed to pay the Company a one-time In June 2022, the Company and Zenas executed the license agreement (“Zenas License”). The Zenas Option and Zenas License are collectively referred to as the “Zenas Agreements.” The Zenas License provides Zenas with a license in the People’s Republic of China, including Hong Kong, Macau, and Taiwan, for the development and commercialization of sequences and products under the first antibody sequence. The Company is also obligated to perform certain research and development and CMC services, and will also participate in a joint steering committee (“JSC”). Under the Zenas License, Zenas also has the right to exercise an option with respect to a second antibody sequence. If Zenas exercises the option and pays the Company the option exercise fee related to the second antibody sequence, the Company will grant Zenas an exclusive license to the sequences and products under this second antibody sequence. Since the Zenas Agreements were negotiated with a single commercial objective, they are treated as a combined contract for accounting purposes. The Company assessed the Zenas Agreements in accordance with ASC 606 and concluded that it represents a contract with a customer and is within the scope of ASC 606. The Company determined that there is one combined performance obligation that consists of the license and data transfer, the research and development and CMC services, and the participation in the JSC. The Company determined that Zenas’ right to exercise an option with respect to a second antibody sequence does not represent a material right. The consideration under the Zenas Agreements includes the following payments by Zenas to the Company: (i) a $1.0 million upfront payment upon execution of the Zenas License; (ii) an approximate $1.1 million payment representing reimbursement for a portion of development costs previously incurred by the Company; (iii) reimbursement of a portion of all CMC-related pre-defined non-CMC-related pre-defined mid-single The Company determined that the combined performance obligation is satisfied over time; therefore, the Company will recognize the transaction price from the license agreement over the Company’s estimated period to complete its activities. The Company concluded that it would utilize a cost-based input method to measure its progress toward completion of its performance obligation and to calculate the corresponding amount of revenue to recognize each period. The Company believes this is the best measure of progress because other measures do not reflect how the Company transfers its performance obligation to Zenas. In applying the cost-based input method of revenue recognition, the Company uses actual costs incurred relative to budgeted costs expected to be incurred for the combined performance obligation. These costs consist primarily of third-party contract costs. Revenue will be recognized based on the level of costs incurred relative to the total budgeted costs for the combined performance obligation. A cost-based input method of revenue recognition requires management to make estimates of costs to complete the Company’s performance obligation. In making such estimates, judgment is required to evaluate assumptions related to cost estimates. The Company also determined that the milestone payments of $11.0 million are variable consideration under ASC 606 which need to be added to the transaction price when it is probable that a significant revenue reversal will not occur. Based on the nature of the milestones, such as the regulatory approvals which are generally not within the Company’s control, the Company will not consider achievement of this milestone to be probable until the uncertainty associated with such milestone has been resolved. When it is probable that a significant reversal of revenue will not occur, the milestone payment will be added to the transaction price for which the Company recognizes revenue. As of September 30, 2023, no milestones have been achieved. There is a sales or usage-based royalty exception within ASC 606 that applies when a license of intellectual property is the predominant item to which the royalty relates. In accordance with this royalty exception, the Company will recognize royalty revenue at the later of (i) when the related sales occur, or (ii) when the performance obligation to which some or all of the royalty has been allocated has been satisfied (or partially satisfied). As of September 30, 2023, no royalty revenue has been recognized. For the three and nine months ended September 30, 2023, the Company recognized related party license revenue totaling $0.9 million and $2.4 million, respectively, associated with the Zenas Agreements. For the three and nine months ended September 30, 2022, the Company recognized related party license revenue totaling $1.2 million and $5.2 million, respectively, associated with the Zenas Agreements. As of September 30, 2023, the Company recorded a related party receivable of $0.2 million, unbilled related party receivable of $0.5 million, current deferred related party revenue of $0.1 million and noncurrent deferred related party revenue of $0.7 million on its unaudited condensed consolidated balance sheet. As of December 31, 2022, the Company recorded a related party receivable of $4.7 million, unbilled related party receivable of $0.9 million, current deferred related party revenue of $0.1 million and noncurrent deferred related party revenue of $0.8 million on its unaudited condensed consolidated balance sheet. | 12. License Revenue—Related Party In September 2020, the Company entered into an Option Agreement with Zenas (“Zenas Option”), a related party (See Note 16). Through the Zenas Option, the Company provided Zenas an option to enter into an exclusive license agreement for the development and commercialization of products arising from its research of monoclonal antibody antagonists targeting certain specific complement proteins. In September 2021, the Company notified Zenas that it had elected the first antibody sequence as a clinical candidate. In October 2021, Zenas notified the Company that it was exercising its option for such clinical candidate. The Zenas Option provided that upon the exercise of the option, the Company would negotiate in good faith a license agreement with Zenas pursuant to which it would grant Zenas the exclusive license with respect to the antibody sequences for the Zenas Territory, which includes People’s Republic of China, including Hong Kong, Macau, and Taiwan. In accordance with Zenas Option, within 60 days following the execution of a license agreement, Zenas agreed to pay the Company a one-time In June 2022, the Company and Zenas executed the license agreement (“Zenas License”). The Zenas Option and Zenas License are collectively referred to as the “Zenas Agreements”. The Zenas License provides Zenas with a license in the People’s Republic of China, including Hong Kong, Macau, and Taiwan, for the development and commercialization of sequences and products under the first antibody sequence. The Company is also obligated to perform certain research and development and CMC services, and will also participate in a joint steering committee (“JSC”). Under the Zenas License, Zenas also has the right to exercise an option with respect to a second antibody sequence. If Zenas exercises the option and pays the Company the option exercise fee related to the second antibody sequence, the Company will grant Zenas an exclusive license to the sequences and products under this second antibody sequence. Since the Zenas Agreements were negotiated with a single commercial objective, they are treated as a combined contract for accounting purposes. The Company assessed the Zenas Agreements in accordance with ASC 606 and concluded that it represents a contract with a customer and is within the scope of ASC 606. The Company determined that there is one combined performance obligation that consists of the license and data transfer, the research and development and CMC services, and the participation in the JSC. The Company determined that Zenas’ right to exercise an option with respect to a second antibody sequence does not represent a material right. The consideration under the Zenas Agreements includes the following payments by Zenas to the Company: (i) a $1 million upfront payment upon execution of the Zenas License; (ii) an approximate $1.1 million payment representing reimbursement for a portion of development costs previously incurred by the Company; (iii) reimbursement of a portion of all CMC-related costs and expenses for the first antibody sequence through the manufacture of the first two batches of drug product; (iv) reimbursement of a portion of all non-CMC-related mid-single The Company determined that the combined performance obligation is satisfied over time; therefore, the Company will recognize the transaction price from the license agreement over the Company’s estimated period to complete its activities. The Company concluded that it will utilize a cost-based input method to measure its progress toward completion of its performance obligation and to calculate the corresponding amount of revenue to recognize each period. The Company believes this is the best measure of progress because other measures do not reflect how the Company transfers its performance obligation to Zenas. In applying the cost-based input method of revenue recognition, the Company uses actual costs incurred relative to budgeted costs expected to be incurred for the combined performance obligation. These costs consist primarily of third-party contract costs. Revenue will be recognized based on the level of costs incurred relative to the total budgeted costs for the combined performance obligation. A cost-based input method of revenue recognition requires management to make estimates of costs to complete the Company’s performance obligation. In making such estimates, judgment is required to evaluate assumptions related to cost estimates. The Company also determined that the milestone payments of $11 million are variable consideration under ASC 606 which need to be added to the transaction price when it is probable that a significant revenue reversal will not occur. Based on the nature of the milestones, such as the regulatory approvals which are generally not within the Company’s control, the Company will not consider achievement of this milestone to be probable until the uncertainty associated with such milestone has been resolved. When it is probable that a significant reversal of revenue will not occur, the milestone payment will be added to the transaction price for which the Company recognizes revenue. As of December 31, 2022, no milestones had been achieved. There is a sales or usage-based royalty exception within ASC 606 that applies when a license of intellectual property is the predominant item to which the royalty relates. In accordance with this royalty exception, the Company will recognize royalty revenue at the later of (i) when the related sales occur, or (ii) when the performance obligation to which some or all of the royalty has been allocated has been satisfied (or partially satisfied). As of December 31, 2022, no royalty revenue has been recognized. For the years ended December 31, 2022 and 2021, the Company recognized related party license revenue totaling $6.4 million and $1.5 million, respectively, associated with the Zenas Agreements. As of December 31, 2022, the Company recorded a related party receivable of $4.7 million, unbilled related party receivable of $0.9 million, current deferred related party revenue of $0.1 million and noncurrent deferred related party revenue of $0.8 million on its balance sheet. |
Income Taxes
Income Taxes | 12 Months Ended |
Dec. 31, 2022 | |
Income Taxes | 13. Income Taxes For the years ended December 31, 2022 and 2021, the Company recorded no current or deferred income tax expenses or benefits as it has incurred losses since inception and has provided a full valuation allowance against its deferred tax assets. A reconciliation of the U.S. federal statutory income tax rate to the Company’s effective income tax rate is as follows: Years Ended 2022 2021 Federal statutory income tax rate 21.0 % 21.0 % State taxes, net of federal benefit 2.2 % 6.3 % Research tax credits 2.2 % 2.5 % Other -3.0 % -0.1 % Increase in deferred tax asset valuation allowance -22.4 % -29.7 % Effective income tax rate 0.0 % 0.0 % The following table provides a summary of net deferred tax assets (in thousands): December 31, 2022 2021 Deferred tax assets: Net operating loss carryforwards $ 5,383 $ 4,651 Tax credit carryforwards 1,120 483 Capitalized research and development costs 4,315 — Accrued expenses 484 57 Share-based compensation 273 4 Lease liabilities 183 — Organizational costs 4 5 Gross deferred tax assets 11,762 5,200 Valuation allowance (11,566 ) (5,194 ) Total deferred tax assets 196 6 Deferred tax liabilities: Right-of-use (189 ) — Prepaid expenses (7 ) (6 ) Net deferred tax assets $ — $ — As of December 31, 2022, the Company had federal net operating loss carryforwards of approximately $24.5 million, all of which have no expiration date and can be carried forward indefinitely; however, they are limited to a deduction to 80% of annual taxable income. The Company had state tax net operating loss carryforwards of approximately $20.1 million, which begin to expire in 2038. In assessing the realizability of the net deferred tax assets, management considers all relevant positive and negative evidence in determining whether it is more likely than not that some portion or all the deferred income tax assets will not be realized. The realization of the gross deferred tax assets is dependent on several factors, including the generation of sufficient taxable income prior to the expiration of the net operating loss carryforwards. Management believes that it is more likely than not that the Company’s deferred income tax assets will not be realized. Changes in the valuation allowance for deferred tax assets during the years ended December 31, 2022 and 2021 related primarily to the increase in net operating loss carryforwards, capitalized research and development expenses and research tax credit carryforwards. During the year ended December 31, 2022, capitalized research and development expenses increased pursuant to Section 174 of the Internal Revenue Code of 1986, as amended (the “Code”). The changes in the valuation allowance for the years ended December 31, 2022 and 2021 and were as follows (in thousands): Years Ended 2022 2021 Valuation allowance as of beginning of year $ 5,194 $ 1,307 Net increases recorded to income tax provision 6,372 3,887 Valuation allowance as of end of year $ 11,566 $ 5,194 Net operating loss carryforwards are subject to review and possible adjustment by the Internal Revenue Service and may become subject to an annual limitation in the event of certain cumulative changes in the ownership interest of significant shareholders over a three-year period in excess of 50% as defined under Sections 382 and 383 in the Code, which could limit the amount of tax attributes that can be utilized annually to offset future taxable income or tax liabilities. The amount of the annual limitation is determined based on the Company’s value immediately prior to the ownership change. Subsequent ownership changes may further affect the limitation in future years. The Company has not yet conducted a study to determine if any such changes have occurred that could limit the ability to use the net operating loss carryforwards. The Company has not recorded any liabilities for unrecognized tax benefits as of December 31, 2022 or 2021. The Company will recognize interest and penalties related to uncertain tax positions, if any, in income tax expense. As of December 31, 2022 and 2021, the Company had no accrued interest or penalties related to uncertain tax positions. |
Net Loss Per Share
Net Loss Per Share | 9 Months Ended | 12 Months Ended |
Sep. 30, 2023 | Dec. 31, 2022 | |
Earnings Per Share [Abstract] | ||
Net Loss Per Share | 14. Net Loss Per Share Basic and diluted net loss per common share were calculated as follows: Three Months Ended Nine Months Ended 2023 2022 2023 2022 Numerator: Net loss $ (14,763 ) $ (7,784 ) $ (32,992 ) $ (18,360 ) Denominator: Weighted-average common shares outstanding 3,907,075 875,279 1,896,983 875,279 Less: weighted-average unvested restricted shares of common stock (189 ) (952 ) (378 ) (1,141 ) Weighted-average shares used to compute net loss per common share, basic and diluted 3,906,886 874,327 1,896,605 874,138 Net loss per share attributable to common stockholders, basic and diluted $ (3.78 ) $ (8.90 ) $ (17.40 ) $ (21.00 ) The Company’s potential dilutive securities, which include convertible preferred stock, stock options, unvested restricted shares of common stock, and warrants for the purchase of common stock, have been excluded from the computation of diluted net loss per share as the effect would be antidilutive. Therefore, the weighted-average number of common shares outstanding used to calculate both basic and diluted net loss per share is the same. The following potential dilutive securities, presented on an as converted basis, were excluded from the calculation of net loss per share due to their anti-dilutive effect: Three Months Ended Nine Months Ended 2023 2022 2023 2022 Convertible preferred stock (as converted) — 7,269,183 — 7,269,183 Stock options outstanding 1,772,179 1,253,415 1,772,179 1,253,415 Unvested restricted shares of common stock 63 826 63 826 Warrants for the purchase of common stock 214,997 4,677 214,997 4,677 Total 1,987,239 8,528,101 1,987,239 8,528,101 | 14. Net Loss Per Share Basic and diluted net loss per common share were calculated as follows (in thousands, except share and per share data): Years Ended 2022 2021 Numerator: Net loss $ (28,476 ) $ (13,109 ) Denominator: Weighted-average common shares outstanding 875,279 875,279 Less: weighted-average unvested restricted shares of common stock (1,045 ) (1,808 ) Weighted-average shares used to compute net loss per common share, basic and diluted 874,234 873,471 Net loss per share attributable to common stockholders, basic and diluted $ (32.57 ) (15.01 ) The Company’s potential dilutive securities, which include convertible preferred stock, stock options, unvested restricted shares of common stock, and warrants for the purchase of common stock, have been excluded from the computation of diluted net loss per share as the effect would be antidilutive. Therefore, the weighted-average number of common shares outstanding used to calculate both basic and diluted net loss per share is the same. The following potential dilutive securities, presented on an as converted basis, were excluded from the calculation of net loss per share due to their anti-dilutive effect: Years Ended December 31, 2022 2021 Convertible preferred stock (as converted) 7,269,183 2,252,357 Stock options outstanding 1,273,454 248,603 Unvested restricted shares of common stock 635 1,398 Warrants for the purchase of common stock 4,677 4,677 Total 8,547,949 2,507,035 |
Commitments and Contingencies
Commitments and Contingencies | 9 Months Ended | 12 Months Ended |
Sep. 30, 2023 | Dec. 31, 2022 | |
Commitments and Contingencies Disclosure [Abstract] | ||
Commitments and Contingencies | 15. Commitments and Contingencies Alloy Therapeutics, LLC In August 2019, the Company entered into a license agreement with Alloy Therapeutics, LLC (“Alloy”). The license agreement was amended in October 2022. The license agreement with Alloy grants to the Company the following: • A worldwide, non-exclusive non-clinical • With respect to Alloy antibodies and platform assisted antibodies that are selected by the Company for inclusion into a partnered antibody program, a worldwide, assignable license to make, have made, use, offer for sale, sell, import, develop, manufacture, and commercialize products comprising partnered antibody programs selected from Alloy antibodies and platform assisted antibodies in any field of use. The Company pays annual license fees and annual partnered antibody program fees totaling $0.1 million to Alloy. The Company is also obligated to pay a $0.1 million fee to Alloy if the Company sublicenses a product developed with Alloy antibodies or platform assisted antibodies. Upon the achievement, with the first selected antibody for products developed with Alloy, of (i) certain development milestones and (ii) certain commercial milestones, the Company is obligated to make additional payments to Alloy of up to $1.8 million and $11.0 million, respectively. Upon the achievement, with the second selected antibody for products developed with Alloy, of (i) certain development milestones and (ii) certain commercial milestones, the Company is obligated to make additional payments to Alloy of up to $3.1 million and $15.0 million, respectively. The Company recorded $50 thousand and $0.1 million during the three and nine months ended September 30, 2023, respectively, and $50 thousand during each of the three and nine months ended September 30, 2022, for amounts owed under the Alloy license agreement within the research and development expenses line item in the unaudited condensed consolidated statement of operations and comprehensive loss. Crystal Bioscience, Inc. and OmniAb, Inc. In September 2022, the Company entered into a commercial platform license agreement and services agreement with Crystal Bioscience, Inc. (“Crystal”) and OmniAb, Inc. (“OmniAb”), both subsidiaries of Ligand Pharmaceuticals Incorporated (collectively, “Ligand”). • Crystal granted the Company a worldwide, non-exclusive, non-sublicensable • OmniAb granted the Company a worldwide, non-exclusive non-sublicensable Upon the achievement of certain development milestones, the Company is obligated to make additional payments to Ligand of up to $12.2 million. Upon the achievement of certain commercial milestones, the Company is obligated to make royalty payments in the low to mid-single IONTAS Limited In July 2020, the Company entered into a collaborative research agreement with IONTAS Limited (“IONTAS”) to perform certain milestone-based research and development activities for the Company under its first development program. This agreement was amended in January 2023 to extend their services to additional development programs. IONTAS provides dedicated resources to perform the research and development activities and receives compensation for those resources as well as success-based milestone payments. Upon the achievement, with the first development program with IONTAS, of (i) certain development milestones and (ii) certain commercial milestones, the Company is obligated to make additional payments to IONTAS of up to £3.1 million (approximately $3.9 million) and £2.3 million (approximately $2.9 million), respectively. Upon the achievement, with the second development program with IONTAS, of certain development milestones, the Company is obligated to make additional payments to IONTAS of up to £2.5 million (approximately $3.1 million). The Company recorded $0.6 million and $2.0 million during the three and nine months ended September 30, 2023, respectively, and $0.2 million and $0.8 million during the three and nine months ended September 30, 2022, respectively, for amounts owed under the IONTAS collaborative research license agreement within the research and development expenses line item in the unaudited condensed consolidated statement of operations and comprehensive loss. Indemnification Agreements In the ordinary course of business, the Company may provide indemnification of varying scope and terms to employees, consultants, vendors, business partners and other parties with respect to certain matters including, but not limited to, losses arising out of breach of such agreements or from intellectual property infringement claims made by third parties. To date, the Company has not incurred any material costs as a result of such indemnification agreements. The Company is not aware of any indemnification arrangements that could have a material effect on its financial position, results of operations or cash flows, and has not accrued any liabilities related to such obligations in its unaudited condensed consolidated financial statements as of September 30, 2023 and December 31, 2022. Litigation From time to time, the Company may be exposed to litigation relating to potential products and operations. The Company is not currently engaged in any legal proceedings that are expected, individually or in the aggregate, to have a material adverse effect on its financial condition, results of operations or cash flows. Other As of September 30, 2023 and December 31, 2022, the Company had standing agreements with consultants, contractors or service providers whose terms do not yield material long-term commitments. | 15. Commitments and Contingencies Alloy Therapeutics, LLC: In August 2019, the Company entered into a license agreement with Alloy Therapeutics, LLC (“Alloy”). The license agreement was amended in October 2022. The license agreement with Alloy grants to the Company the following: • A worldwide, non-exclusive non-clinical • With respect to Alloy antibodies and platform assisted antibodies that are selected by the Company for inclusion into a partnered antibody program, a worldwide, assignable license to make, have made, use, offer for sale, sell, import, develop, manufacture, and commercialize products comprising partnered antibody programs selected from Alloy antibodies and platform assisted antibodies in any field of use. The Company pays annual license fees and annual partnered antibody program fees totaling $0.1 million to Alloy. The Company is also obligated to pay a $0.1 million fee to Alloy if the Company sublicenses a product developed with Alloy antibodies or platform assisted antibodies. Upon the achievement, with the first selected antibody for products developed with Alloy, of (i) certain development milestones and (ii) certain commercial milestones, the Company is obligated to make additional payments to Alloy of up to $1.8 million and $11.0 million, respectively. Upon the achievement, with the second selected antibody for products developed with Alloy, of (i) certain development milestones and (ii) certain commercial milestones, the Company is obligated to make additional payments to Alloy of up to $3.1 million and $15.0 million, respectively. The Company recorded $0.5 million and $0.1 million for amounts owed under the Alloy license agreement within the research and development expenses line item in the statements of operations and comprehensive loss during the years ended December 31, 2022 and 2021, respectively. Crystal Bioscience, Inc. and OmniAb, Inc.: In September 2022, the Company entered into a commercial platform license agreement and services agreement with Crystal Bioscience, Inc. (“Crystal”) and OmniAb, Inc. (“OmniAb”), both subsidiaries of Ligand Pharmaceuticals Incorporated (collectively, “Ligand”). • Crystal granted the Company a worldwide, non-exclusive, • OmniAb granted the Company a worldwide, non-exclusive Upon the achievement of certain development milestones, the Company is obligated to make additional payments to Ligand of up to $12.2 million. Upon the achievement of certain commercial milestones, the Company is obligated to make royalty payments in the low to mid-single IONTAS Limited: In July 2020, the Company entered into a collaborative research agreement with IONTAS Limited (“IONTAS”) to perform certain milestone-based research and development activities for the Company under its first development program. This agreement was amended in January 2023 to extend their services to additional development programs. IONTAS provides dedicated resources to perform the research and development activities and receives compensation for those resources as well as success-based milestone payments. Upon the achievement, with the first development program with IONTAS, of (i) certain development milestones and (ii) certain commercial milestones, the Company is obligated to make additional payments to IONTAS of up to £3.1 million and £2.3 million, respectively. Upon the achievement, with the second development program with IONTAS, of certain development milestones, the Company is obligated to make additional payments to IONTAS of up to £2.5 million. The Company has recorded $1.7 million and $2.7 million for amounts owed under the IONTAS collaborative research license agreement within the research and development expenses line item in the statements of operations and comprehensive loss during the years ended December 31, 2022 and 2021, respectively. Indemnification Agreements In the ordinary course of business, the Company may provide indemnification of varying scope and terms to employees, consultants, vendors, business partners and other parties with respect to certain matters including, but not limited to, losses arising out of breach of such agreements or from intellectual property infringement claims made by third parties. To date, the Company has not incurred any material costs as a result of such indemnification agreements. The Company is not aware of any indemnification arrangements that could have a material effect on its financial position, results of operations or cash flows, and has not accrued any liabilities related to such obligations in its financial statements as of December 31, 2022 or 2021. Litigation From time to time, the Company may be exposed to litigation relating to potential products and operations. The Company is not currently engaged in any legal proceedings that are expected, individually or in the aggregate, to have a material adverse effect on its financial condition, results of operations or cash flows. Other As of December 31, 2022 and 2021, the Company had standing agreements with consultants, contractors or service providers whose terms do not yield material long-term commitments. |
Related Party Transactions
Related Party Transactions | 9 Months Ended | 12 Months Ended |
Sep. 30, 2023 | Dec. 31, 2022 | |
Related Party Transactions [Abstract] | ||
Related Party Transactions | 16. Related Party Transactions Viridian, LLC In June 2019, the Company entered into a Technology Assignment Agreement (the “TAA”) with Viridian, LLC (“Viridian”), a related party. The Company considers Viridian to be a related party because two of its members have a seat on the Board of Directors of the Company. The TAA assigns to the Company exclusively throughout the world all rights, title, and interest to all technology and know-how Zenas BioPharma Limited The Company is a party to option and license agreements with Zenas, a related party. The Company considers Zenas to be a related party because (i) Tellus BioVentures LLC (“Tellus”), whose sole member is a significant shareholder in the Company and serves as Chairman of the Board of Directors of the Company, is also a significant shareholder in Zenas and serves as Chief Executive Officer and Chairman of the Board of Directors of Zenas and (ii) Fairmount Healthcare Fund LP and Fairmount Healthcare Fund II LP (together, the “Fairmount Funds”), who are significant shareholders in the Company and have a seat on the Board of Directors of the Company, are also significant shareholders in Zenas and have a seat on the Board of Directors of Zenas. As of September 30, 2023, Tellus and affiliated entities owned approximately 10%, and the Fairmount Funds and affiliated entities owned approximately 13% of the Company’s outstanding shares. See Note 13 for more information. In connection with these agreements, the Company recognized $0.9 million and $2.4 million within the license revenue – related party line item in the unaudited condensed consolidated statements of operations and comprehensive loss for the three and nine months ended September 30, 2023, respectively. In connection with these agreements, the Company recognized $1.2 million and $5.2 million within the license revenue – related party line item in the unaudited condensed consolidated statements of operations and comprehensive loss for the three and nine months ended September 30, 2022, respectively. As of September 30, 2023, the Company recorded a related party receivable of $0.2 million, unbilled related party receivable of $0.5 million, current deferred related party revenue of $0.1 million and noncurrent deferred related party revenue of $0.7 million on its unaudited condensed consolidated balance sheet. As of December 31, 2022, the Company recorded a related party receivable of $4.7 million, unbilled related party receivable of $0.9 million, current deferred related party revenue of $0.1 million and noncurrent deferred related party revenue of $0.8 million on its unaudited condensed consolidated balance sheet. In 2020, Zenas issued 156,848 common shares to the Company in exchange for the Zenas Option. The Company determined that the fair value on the date of issuance and as of September 30, 2023 and December 31, 2022, respectively, was not material to its unaudited condensed consolidated financial statements. The Company used the measurement alternative as the measurement attribute for accounting for the Zenas common shares which does not require it to assess the fair value of the common stock at each reporting period as the fair value of the Zenas common shares is not readily determinable nor is there a reliable source for observable transactions from which the Company could determine a fair value. In addition, the Company does not have ready access to significant events occurring at Zenas. If the Company does identify observable price changes in orderly transactions for the identical or similar common shares of Zenas, the Company will measure the common shares at fair value as of the date that the observable transaction occurred. On March 13, 2023, the Fairmount Funds issued promissory notes in the aggregate principal amount of $0.4 million Former Dianthus at an interest rate of 4.5% per annum. On March 15, 2023, Former Dianthus repaid principal and interest in the amount of $0.4 million to the Fairmount Funds in satisfaction of its obligations under the promissory notes. | 16. Related Party Transactions Viridian, LLC: In June 2019, the Company entered into a Technology Assignment Agreement (the “TAA”) with Viridian, LLC (“Viridian”), a related party. The Company considers Viridian to be a related party because two of its members have a seat on the Board of Directors of the Company. The TAA assigns to the Company exclusively throughout the world all rights, title, and interest to all technology and know-how with a fair value of $0.09 per share. There are no future obligations to Viridian in connection with the TAA. As of December 31, 2022 and 2021, Viridian owned approximately 13% and 35%, respectively, of the Company’s outstanding shares (assuming the conversion of all preferred stock into common stock). Zenas BioPharma Limited: The Company is a party to option and license agreements with Zenas, a related party. The Company considers Zenas to be a related party because (i) Tellus BioVentures LLC (“Tellus”), whose sole member is a significant shareholder in the Company and serves as Chairman of the Board of Directors of the Company, is also a significant shareholder in Zenas and serves as Executive Chairman of the Board of Directors of Zenas and (ii) the Fairmount Funds, who are significant shareholders in the Company and have a seat on the Board of Directors of the Company, are also significant shareholders in Zenas and have a seat on the Board of Directors of Zenas. As of December 31, 2022 and 2021, Tellus and affiliated entities owned approximately 17% and 42%, respectively, and Fairmount Funds and affiliated entities owned approximately 14% and 13%, respectively, of the Company’s outstanding shares (assuming the conversion of all preferred stock into common stock). See Note 12 for more information. In connection with these agreements, the Company recognized $6.4 million and $1.5 million within the license revenue—related party line item in the statements of operations and comprehensive loss for the years ended December 31, 2022 and 2021, respectively. As of December 31, 2022, the Company recorded a related party receivable of $4.7 million, unbilled related party receivable of $0.9 million, current deferred related party revenue of $0.1 million and noncurrent deferred related party revenue of $0.8 million on its balance sheet. As of December 31, 2021, the Company recorded a related party receivable of $0.5 million and unbilled related party receivable of $1.0 million on its balance sheet. In 2020, Zenas issued 156,848 common shares to the Company in exchange for the Zenas Option. The Company determined that the fair value on the date of issuance and as of December 31, 2022 and 2021, respectively, was not material to its financial statements. The Company used the measurement alternative as the measurement attribute for accounting for the Zenas common shares which does not require it to assess the fair value of the common stock at each reporting period as the fair value of the Zenas common shares is not readily determinable nor is there a reliable source for observable transactions from which the Company could determine a fair value. In addition, the Company does not have ready access to significant events occurring at Zenas. If the Company does identify observable price changes in orderly transactions for the identical or similar common shares of Zenas, the Company will measure the common shares at fair value as of the date that the observable transaction occurred. |
Subsequent Events
Subsequent Events | 9 Months Ended | 12 Months Ended |
Sep. 30, 2023 | Dec. 31, 2022 | |
Subsequent Events [Abstract] | ||
Subsequent Events | 17. Subsequent Events The Company evaluated subsequent events from September 30, 2023, the date of these unaudited condensed consolidated financial statements, through November 9, 2023, which represents the date the unaudited condensed consolidated financial statements were issued, for events requiring recording or disclosure in the unaudited condensed consolidated financial statements for the three and nine months ended September 30, 2023. The Company concluded that no events have occurred that would require recognition or disclosure in the unaudited condensed consolidated financial statements. | 17. Subsequent Events Management has evaluated subsequent events through May 15, 2023, the date which the financial statements were available to be issued and determined that there were no additional subsequent events requiring recording or disclosure in the Company’s financial statements except as noted below. The Company issued 209,046 stock option awards from the 2019 Plan during the period January 1, 2023 until May 15, 2023. |
Summary of Significant Accoun_2
Summary of Significant Accounting Policies (Policies) | 9 Months Ended | 12 Months Ended |
Sep. 30, 2023 | Dec. 31, 2022 | |
Basis of Presentation | Basis of Presentation The accompanying unaudited condensed consolidated financial statements as of September 30, 2023 and for the nine months ended September 30, 2023 and 2022 have been prepared in conformity with U.S. GAAP, for interim financial information and pursuant to Article 10 of Regulation S-X period. The unaudited condensed consolidated balance sheet as of December 31, 2022 has been derived from the audited financial statements at that date but does not include all disclosures required by U.S. GAAP for complete financial statements. Because all of the disclosures required by U.S. GAAP for complete financial statements are not included herein, these unaudited condensed consolidated financial statements and the notes accompanying them should be read in conjunction with the Former Dianthus’ audited financial statements as of and for the years ended December 31, 2022 and 2021, included as Exhibit 99.5 of the Company’s Current Report on Form 8-K | Basis of Presentation The financial statements have been prepared in conformity with U.S. generally accepted accounting principles (“U.S. GAAP”). Any reference in these notes to applicable guidance is meant to refer to authoritative U.S. GAAP as found in the Accounting Standards Codification (“ASC”) and Accounting Standards Updates (“ASU”) of the Financial Accounting Standards Board (“FASB”). |
Use of Estimates | Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of expenses during the reporting period. Actual results may differ materially from those estimates. Management considers many factors in selecting appropriate financial accounting policies and controls, and in developing the estimates and assumptions that are used in the preparation of these financial statements. Management must apply significant judgment in this process. In addition, other factors may affect estimates including the following: expected business and operational changes, sensitivity and volatility associated with the assumptions used in developing estimates, and whether historical trends are expected to be representative of future trends. The estimation process often may yield a range of potentially reasonable estimates of the ultimate future outcomes, and management must select an amount that falls within that range of reasonable estimates. Significant estimates are used in the following areas, among others: the recognition of research and development expense, stock-based compensation expense and revenue recognition. | Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of expenses during the reporting period. Actual results may differ materially from those estimates. Management considers many factors in selecting appropriate financial accounting policies and controls, and in developing the estimates and assumptions that are used in the preparation of these financial statements. Management must apply significant judgment in this process. In addition, other factors may affect estimates including the following: expected business and operational changes, sensitivity and volatility associated with the assumptions used in developing estimates, and whether historical trends are expected to be representative of future trends. The estimation process often may yield a range of potentially reasonable estimates of the ultimate future outcomes, and management must select an amount that falls within that range of reasonable estimates. Significant estimates are used in the following areas, among others: the recognition of research and development expense, stock-based compensation expense and revenue recognition. |
Cash and Cash Equivalents | Cash and Cash Equivalents All short-term, highly liquid investments with original maturities of 90 days or less are considered to be cash and cash equivalents. The carrying amounts reported in the unaudited condensed consolidated balance sheets for cash and cash equivalents are valued at cost, which approximates fair value. | Cash and Cash Equivalents All short-term, |
Concentration of Credit Risk | Concentration of Credit Risk Financial instruments that potentially subject the Company to concentrations of credit risk consist principally of cash, cash equivalents and short-term investments. The Company regularly maintains deposits in accredited financial institutions in excess of federally insured limits. The Company invests its excess cash primarily in money market funds, U.S. treasury securities and U.S. government agency securities in accordance with the Company’s investment policy. The Company’s investment policy defines allowable investments and establishes guidelines relating to credit quality, diversification, and maturities of its investments to preserve principal and maintain liquidity. The Company has not experienced any realized losses related to its cash, cash equivalents and short-term investments and management believes the Company is not exposed to significant risks of losses. As of September 30, 2023 and December 31, 2022, the Company held cash deposits at Silicon Valley Bank (“SVB”) in excess of government insured limits. On March 10, 2023, SVB was closed by the California Department of Financial Protection and Innovation, and the Federal Deposit Insurance Corporation was appointed as receiver. No losses were incurred by the Company on deposits that were held at SVB. Management believes that the Company is not currently exposed to significant credit risk as the vast majority of the Company’s deposits were either owned directly by the Company and held in custody at a third-party financial institution or, subsequent to March 10, 2023, have been transferred to a third-party financial institution. The Company does not currently have any other significant relationships with SVB. | Concentration of Credit Risk Financial instruments that potentially subject the Company to concentrations of credit risk consist principally of cash, cash equivalents and short-term investments. The Company regularly maintains deposits in accredited financial institutions in excess of federally insured limits. The Company invests its excess cash primarily in money market funds, U.S. treasury securities and U.S. government agency securities in accordance with the Company’s investment policy. The Company’s investment policy defines allowable investments and establishes guidelines relating to credit quality, diversification, and maturities of its investments to preserve principal and maintain liquidity. The Company has not experienced any realized losses related to its cash, cash equivalents and short-term investments and management believes the Company is not exposed to significant risks of losses. As of December 31, 2022, the Company held cash deposits at Silicon Valley Bank (“SVB”) in excess of government insured limits. On March 10, 2023, SVB was closed by the California Department of Financial Protection and Innovation, and the Federal Deposit Insurance Corporation was appointed as receiver. No losses were incurred by the Company on deposits that were held at SVB. Management believes that the Company is not currently exposed to significant credit risk as the vast majority of the Company’s deposits were either owned directly by the Company and held in custody at a third-party financial institution or, subsequent to March 10, 2023, have been transferred to a third-party financial institution. The Company does not currently have any other significant relationships with SVB. |
Short-term Investments | Short-term Investments Short-term investments consist of investments in U.S. treasury and U.S. government agency securities. Management of the Company determines the appropriate classification of the securities at the time they are acquired and evaluates the appropriateness of such classifications at each balance sheet date. The Company classifies its short-term investments as available-for-sale Investments – Debt and Equity Securities, Effective January 1, 2023, when the fair value is below the amortized cost of a marketable security, an estimate of expected credit losses is made. The credit-related impairment amount is recognized in the unaudited condensed consolidated statements of operations and comprehensive loss. Credit losses are recognized through the use of an allowance for credit losses account in the unaudited condensed consolidated balance sheet and subsequent improvements in expected credit losses are recognized as a reversal of an amount in the allowance account. If the Company has the intent to sell the security or it is more likely than not that the Company will be required to sell the security prior to recovery of its amortized cost basis, then the allowance for the credit loss is written-off Additional information regarding short-term investments is included in Note 4. | Short-term Investments Short-term investments consist of investments in U.S. treasury and U.S. government agency securities. Management of the Company determines the appropriate classification of the securities at the time they are acquired and evaluates the appropriateness of such classifications at each balance sheet date. The Company classifies its short-term investments as available-for-sale Investments—Debt and Equity Securities |
Receivable from Related Party and Unbilled Receivable from Related Party | Receivable from Related Party and Unbilled Receivable from Related Party The receivable from related party and unbilled receivable from related party results from option and license agreements with Zenas BioPharma Limited (“Zenas”), a related party. See Notes 13 and 16 for more information. The receivable represents amounts earned and billed to Zenas but not yet collected while unbilled receivable represents amounts earned but not yet billed to Zenas. The receivable and unbilled receivable are reported at net realizable value. The Company regularly evaluates the creditworthiness of Zenas and their financial condition and does not require collateral from Zenas. As of September 30, 2023 and December 31, 2022, no allowance for doubtful accounts was recorded as all accounts were considered collectible. | Receivable from Related Party and Unbilled Receivable from Related Party The receivable from related party and unbilled receivable from related party results from option and license agreements with Zenas BioPharma Limited (“Zenas”), a related party. See Notes 12 and 16 for more information. The receivable represents amounts earned and billed to Zenas but not yet collected while unbilled receivable represents amounts estimated to be earned but not yet billed to Zenas. The receivable and unbilled receivable are reported at net realizable value. Management of the Company regularly evaluates the creditworthiness of Zenas and their financial condition and does not require collateral from Zenas. As of December 31, 2022 and 2021, no allowance for doubtful accounts was recorded as all accounts were considered collectible. |
Property and Equipment | Property and Equipment Property and equipment are recorded at cost. Depreciation is provided using the straight-line method over estimated useful lives of three years for computer equipment and five years for furniture and fixtures. Expenditures for major renewals and betterments that extend the useful lives are capitalized. Expenditures for normal maintenance and repairs are expensed as incurred. The cost of assets sold or abandoned, and the related accumulated depreciation are eliminated from the accounts and any gains or losses are recognized in the accompanying unaudited condensed consolidated statements of operations and comprehensive loss of the respective period. | Property and Equipment Property and equipment are recorded at cost. Depreciation is provided using the straight-line method over estimated useful lives of three years for computer equipment and five years for furniture and fixtures. Expenditures for major renewals and betterments that extend the useful lives are capitalized. Expenditures for normal maintenance and repairs are expensed as incurred. The cost of assets sold or abandoned, and the related accumulated depreciation are eliminated from the accounts and any gains or losses are recognized in the accompanying statements of operations and comprehensive loss of the respective period. |
Leases | Leases Operating leases are accounted for in accordance with ASU 2016-02, Leases Right-of-use based on the present value of future lease payments over the lease term. As the Company’s leases do not provide an implicit rate, management used the Company’s incremental borrowing rate based on the information available at the lease commencement date in determining the present value of future lease payments. The right-of-use right-of-use The Company’s leases do not have significant rent escalation, holidays, concessions, material residual value guarantees, material restrictive covenants or contingent rent provisions. The Company’s leases include both lease (e.g., fixed payments including rent, taxes, and insurance costs) and non-lease non-lease Additional information and disclosures required under ASC 842 are included in Note 9. | Leases Operating leases are accounted for in accordance with ASU 2016-02, Leases Right-of-use right-of-use right-of-use The Company’s leases do not have significant rent escalation, holidays, concessions, material residual value guarantees, material restrictive covenants or contingent rent provisions. The Company’s leases include both lease (e.g., fixed payments including rent, taxes, and insurance costs) and non-lease non-lease Additional information and disclosures required under ASC 842 are included in Note 8. |
Restricted Cash | Restricted Cash In accordance with ASU 2016-18, Statement of Cash Flows (Topic 230): Restricted Cash | Restricted Cash In accordance with ASU 2016-18, Statement of Cash Flows (Topic 230): Restricted Cash |
Fair Value Measurements | Fair Value Measurements The Company calculates the fair value of assets and liabilities that qualify as financial instruments and includes additional information in the notes to the financial statements when the fair value is different than the carrying value of these financial instruments. The Company is required to disclose information on all assets and liabilities reported at fair value that enables an assessment of the inputs used in determining the reported fair values. ASC Topic 820, Fair Value Measurements and Disclosures Observable inputs are inputs that market participants would use in pricing the asset or liability based on market data obtained from sources independent of the Company. Unobservable inputs are inputs that reflect management’s assumptions about the inputs that market participants would use in pricing the asset or liability and are developed based on the best information available in the circumstances. The fair value hierarchy applies only to the valuation inputs used in determining the reported fair value of the investments and is not a measure of the investment credit quality. The three levels of the fair value hierarchy are described below: • Level 1—Quoted prices in active markets for identical assets or liabilities. • Level 2—Observable inputs other than quoted prices included in Level 1, such as quoted prices for similar assets and liabilities in active markets; quoted prices for identical or similar assets and liabilities in markets that are not active; or other inputs that are observable or can be corroborated by observable market data. • Level 3—Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets and liabilities. This includes certain pricing models, discounted cash flow methodologies and similar valuation techniques that use significant unobservable inputs. To the extent that a valuation is based on models or inputs that are less observable or unobservable in the market, the determination of fair value requires more judgment. Accordingly, the degree of judgment exercised by management in determining fair value is greatest for instruments categorized in Level 3. A financial instrument’s level within the fair value hierarchy is based on the lowest level of any input that is significant to the fair value measurement. Management has segregated all financial assets and liabilities that are measured at fair value on a recurring basis into the most appropriate level within the fair value hierarchy based on the inputs used to determine the fair value at the measurement date in the table below. The Company’s valuation techniques for its Level 2 financial assets included using quoted prices for similar assets in active markets and quoted prices for similar assets in markets that are not active. The estimated fair value of receivable from related party, unbilled receivable from related party, accounts payable and accrued expenses approximate their carrying amounts due to the relatively short maturity of these instruments. Additional information regarding fair value measurements is included in Note 7. | |
Convertible Preferred Stock | Convertible Preferred Stock Convertible preferred stock is recorded at its original issuance price, less direct and incremental offering costs, as stipulated by its terms. The Company has applied the guidance in ASC 480-10-S99, Distinguishing Liabilities from Equity-Overall-SEC | Classification of Convertible Preferred Stock Convertible preferred stock is recorded at its original issuance price, less direct and incremental offering costs, as stipulated by its terms. The Company has adopted the guidance in ASC 480-10-S99, Distinguishing Liabilities from Equity-Overall-SEC Effective January 1, 2021, the Company early adopted ASU 2020-06, Debt—Debt with Conversion and Other Options (Subtopic 470-20) |
Segment Information | Segment Information Operating segments are defined as components of an entity for which separate financial information is available and that is regularly reviewed by the Chief Operating Decision Maker (“CODM”) in deciding how to allocate resources and in assessing performance. The Company’s CODM is its Chief Executive Officer (“CEO”). The Company operates as a single operating segment and has one reportable segment. | Segment Information Operating segments are defined as components of an entity for which separate financial information is available and that is regularly reviewed by the Chief Operating Decision Maker (“CODM”) in deciding how to allocate resources and in assessing performance. The Company’s CODM is its Chief Executive Officer (“CEO”). The Company operates as a single one |
License Revenue - Related Party | License Revenue – Related Party To date, the Company’s only revenue has been attributable to an upfront payment and cost reimbursements under the Company’s license agreement with Zenas. The Company has not generated any revenue from product sales and does not expect to generate any revenue from product sales for the foreseeable future. The Company recognizes revenue pursuant to ASC 606, Revenue from Contracts with Customers (ii) identify the performance obligations in the contract; (iii) determine the transaction price; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when the performance obligation is satisfied. The Company evaluates the performance obligations promised in a contract that are based on goods and services that will be transferred to the customer and determine whether those obligations are both (i) capable of being distinct and (ii) distinct in the context of the contract. To the extent a contract includes multiple promised goods and services, the Company applies judgment to determine whether promised goods and services are both capable of being distinct and are distinct in the context of the contract. If these criteria are not met, the promised goods and services are accounted for as a combined performance obligation. Arrangements that include rights to additional goods or services that are exercisable at a customer’s discretion are generally considered options. The Company assesses if these options provide a material right to the customer and if so, they are considered performance obligations. The Company estimates the transaction price based on the amount expected to be received for transferring the promised goods or services in the contract. The consideration may include fixed consideration or variable consideration. At the inception of each arrangement that includes variable consideration, the Company evaluates the amount of potential transaction price and the likelihood that the transaction price will be received. Variable consideration is included in the transaction price if, in management’s judgment, it is probable that a significant future reversal of cumulative revenue under the contract will not occur. Any estimates, including the effect of the constraint on variable consideration, are evaluated at each reporting period for any changes. The Company then allocates the transaction price to each performance obligation and recognizes as revenue the amount of the transaction price that is allocated to the respective performance obligation when (or as) control is transferred to the customer and the performance obligation is satisfied. Amounts received prior to satisfying the revenue recognition criteria are recorded as deferred revenue in the Company’s balance sheets. If the related performance obligation is expected to be satisfied within the next twelve months this will be classified in current liabilities. Additional information and disclosures required under ASC 606 are included in Note 13. | License Revenue—Related Party To date, the Company’s only revenue has been attributable to an upfront payment and cost reimbursements under the Company’s license agreement with Zenas. The Company has not generated any revenue from product sales and does not expect to generate any revenue from product sales for the foreseeable future. The Company recognizes revenue pursuant to ASC 606, Revenue from Contracts with Customers goods or services, in an amount that reflects the consideration that the entity expects to receive in exchange for those goods or services. To determine revenue recognition for arrangements that an entity determines are within the scope of ASC 606, the entity performs the following five steps: (i) identify the contract with a customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when the performance obligation is satisfied. The Company evaluates the performance obligations promised in a contract that are based on goods and services that will be transferred to the customer and determine whether those obligations are both (i) capable of being distinct and (ii) distinct in the context of the contract. To the extent a contract includes multiple promised goods and services, the Company applies judgment to determine whether promised goods and services are both capable of being distinct and are distinct in the context of the contract. If these criteria are not met, the promised goods and services are accounted for as a combined performance obligation. Arrangements that include rights to additional goods or services that are exercisable at a customer’s discretion are generally considered options. The Company assesses if these options provide a material right to the customer and if so, they are considered performance obligations. The Company estimates the transaction price based on the amount expected to be received for transferring the promised goods or services in the contract. The consideration may include fixed consideration or variable consideration. At the inception of each arrangement that includes variable consideration, the Company evaluates the amount of potential transaction price and the likelihood that the transaction price will be received. Variable consideration is included in the transaction price if, in management’s judgment, it is probable that a significant future reversal of cumulative revenue under the contract will not occur. Any estimates, including the effect of the constraint on variable consideration, are evaluated at each reporting period for any changes. The Company then allocates the transaction price to each performance obligation and recognizes as revenue the amount of the transaction price that is allocated to the respective performance obligation when (or as) control is transferred to the customer and the performance obligation is satisfied. Amounts received prior to satisfying the revenue recognition criteria are recorded as deferred revenue in the Company’s balance sheets. If the related performance obligation is expected to be satisfied within the next twelve months this will be classified in current liabilities. Additional information and disclosures required under ASC 606 are included in Note 12. |
Research and Development Costs | Research and Development Costs Research and development expenses are recorded as expense, as incurred. Research and development expenses consists of (i) costs to engage contractors who specialize in the development activities of the Company; (ii) external research and development costs incurred under arrangements with third parties, such as contract research organizations and consultants; and (iii) costs associated with preclinical activities and regulatory operations. The Company enters into consulting, research, and other agreements with commercial firms, researchers, and others for the provision of goods and services. Under such agreements, the Company may pay for services on a monthly, quarterly, project or other basis. Such arrangements are generally cancelable upon reasonable notice and payment of costs incurred. Costs are considered incurred based on an evaluation of the progress to completion of specific tasks under each contract using information and data provided by the service providers and vendors, whereas payments are dictated by the terms of each agreement. As such, depending on the timing of payment relative to the receipt of goods or services, management may record either prepaid expenses or accrued services. These costs consist of direct and indirect costs associated with specific projects, as well as fees paid to various entities that perform certain research on behalf of the Company. | Research and Development Costs Research and development expenses are recorded as expense, as incurred. Research and development expenses consists of (i) costs to engage contractors who specialize in the development activities of the Company; (ii) external research and development costs incurred under arrangements with third parties, such as contract research organizations and consultants; and (iii) costs associated with preclinical activities and regulatory operations. The Company enters into consulting, research, and other agreements with commercial firms, researchers, and others for the provision of goods and services. Under such agreements, the Company may pay for services on a monthly, quarterly, project or other basis. Such arrangements are generally cancellable upon reasonable notice and payment of costs incurred. Costs are considered incurred based on an evaluation of the progress to completion of specific tasks under each contract using information and data provided by the service providers and vendors, whereas payments are dictated by the terms of each agreement. As such, depending on the timing of payment relative to the receipt of goods or services, management may record either prepaid expenses or accrued services. These costs consist of direct and indirect costs associated with specific projects, as well as fees paid to various entities that perform certain research on behalf of the Company. |
Patent costs | Patent costs Patent costs are expensed as incurred and recorded within general and administrative expenses. | Patent costs Patent costs are expensed as incurred and recorded within general and administrative expenses. |
Income Taxes | Income Taxes Income taxes are recorded in accordance with ASC 740, Income Taxes The Company accounts for uncertain tax positions in accordance with the provisions of ASC 740. When uncertain tax positions exist, the Company recognizes the tax benefit of tax positions to the extent that the benefit will more likely than not be realized. The determination as to whether the tax benefit will more likely than not be realized is based upon the technical merits of the tax position, as well as consideration of the available facts and circumstances. As of September 30, 2023 and December 31, 2022, the Company did not have any material uncertain tax positions. The Company recognizes interest and penalties related to uncertain tax positions, if any exist, in income tax expense. | Income Taxes Income taxes are recorded in accordance with ASC 740, Income Taxes ( The Company accounts for uncertain tax positions in accordance with the provisions of ASC 740. When uncertain tax positions exist, the Company recognizes the tax benefit of tax positions to the extent that the benefit will more likely than not be realized. The determination as to whether the tax benefit will more likely than not be realized is based upon the technical merits of the tax position, as well as consideration of the available facts and circumstances. As of December 31, 2022 and 2021, the Company did not have any material uncertain tax positions. The Company recognizes interest and penalties related to uncertain tax positions, if any exist, in income tax expense. |
Stock-Based Compensation | Stock-Based Compensation The Company accounts for stock-based compensation awards in accordance with ASC Topic 718, Compensation – Stock Compensation Prior to the Reverse Merger, management utilized valuation methodologies in accordance with the framework of the American Institute of Certified Public Accountants Technical Practice Aid, Valuation of Privately Held Company Equity Securities Issued as Compensation Due to a lack of company-specific historical and implied volatility data, management bases its estimate of expected volatility on the historical volatility of a representative group of companies with similar characteristics to the Company, including stage of product development and life science industry focus. Management believes the group selected has sufficiently similar economic and industry characteristics and includes companies that are most representative of the Company. Management uses the simplified method, as prescribed by the SEC Staff Accounting Bulletin No. 107, Share-Based Payment rates appropriate for the term of the awards. The dividend yield assumption is based on history and expectation of paying no dividends. Compensation expense related to stock-based awards is calculated on a straight-line basis by recognizing the grant date fair value, over the associated service period of the award, which is generally the vesting term. Additional information regarding share-based compensation is included in Note 12. | Stock-Based Compensation The Company accounts for stock-based compensation awards in accordance with ASC Topic 718, Compensation —Stock Compensation Management utilizes estimates and assumptions in determining the fair value of the Company’s common stock. Stock options were granted at exercise prices that represented the fair value of the Company’s common stock on the specific grant dates. Management utilized valuation methodologies in accordance with the framework of the American Institute of Certified Public Accountants Technical Practice Aid, Valuation of Privately Held Company Equity Securities Issued as Compensation Due to the lack of a historical public market for the trading of the Company’s common stock and a lack of company-specific historical and implied volatility data, management based its estimate of expected volatility on the historical volatility of a representative group of companies with similar characteristics to the Company, including stage of product development and life science industry focus. Management believes the group selected has sufficient similar economic and industry characteristics and includes companies that are most representative of the Company. Management used the simplified method, as prescribed by the SEC Staff Accounting Bulletin No. 107, Share-Based Payment Compensation expense related to stock-based awards is calculated on a straight-line basis by recognizing the grant date fair value, over the associated service period of the award, which is generally the vesting term. |
Comprehensive Loss | Comprehensive Loss The only component of comprehensive loss other than net loss is change in unrealized losses related to available-for-sale | Comprehensive Loss The only component of comprehensive loss other than net loss is change in unrealized losses related to available-for-sale |
Net Loss per Share | Net Loss per Share Basic and diluted net loss per share attributable to common stockholders are calculated in conformity with the two-class two-class Diluted net loss per share of common stock includes the effect, if any, from the potential exercise or conversion of securities, such as convertible preferred stock, stock options and unvested restricted common stock, which would result in the issuance of incremental shares of common stock. For diluted net loss per share, the weighted-average number of shares of common stock is the same for basic net loss per share due to the fact that when a net loss exists, dilutive securities are not included in the calculation as the impact is anti-dilutive. For all periods presented, basic and diluted net loss per share were the same, as any additional share equivalents would be anti-dilutive. Additional information is included in Note 14. | Net Loss per Share Basic net income (loss) per share attributable to common stockholders is computed by dividing the net income (loss) by the weighted average number of shares of common stock outstanding for the period. Diluted net income (loss) per share attributable to common stockholders is computed by dividing net income (loss) by the weighted average number of common shares outstanding for the period, including potential dilutive common shares. For periods in which the Company has reported net losses, diluted net loss per share attributable to common stockholders is the same as basic net loss per share attributable to common stockholders, since dilutive common shares are not assumed to have been issued if their impact is anti-dilutive. Additional information is included in Note 14. |
Recently Adopted Accounting Pronouncements | Recently Adopted Accounting Pronouncements On January 1, 2023, the Company adopted ASU No. 2016-13, Financial Instruments – Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments available-for-sale, | Recently Issued Accounting Pronouncements In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments—Credit Losses (Topic 326) No. 2019-10, |
Summary of Significant Accoun_3
Summary of Significant Accounting Policies (Tables) | 9 Months Ended | 12 Months Ended |
Sep. 30, 2023 | Dec. 31, 2022 | |
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share | The following potential dilutive securities, presented on an as converted basis, were excluded from the calculation of net loss per share due to their anti-dilutive effect: Three Months Ended Nine Months Ended 2023 2022 2023 2022 Convertible preferred stock (as converted) — 7,269,183 — 7,269,183 Stock options outstanding 1,772,179 1,253,415 1,772,179 1,253,415 Unvested restricted shares of common stock 63 826 63 826 Warrants for the purchase of common stock 214,997 4,677 214,997 4,677 Total 1,987,239 8,528,101 1,987,239 8,528,101 | The following potential dilutive securities, presented on an as converted basis, were excluded from the calculation of net loss per share due to their anti-dilutive effect: Years Ended December 31, 2022 2021 Convertible preferred stock (as converted) 7,269,183 2,252,357 Stock options outstanding 1,273,454 248,603 Unvested restricted shares of common stock 635 1,398 Warrants for the purchase of common stock 4,677 4,677 Total 8,547,949 2,507,035 |
Reverse Merger (Tables)
Reverse Merger (Tables) | 9 Months Ended |
Sep. 30, 2023 | |
Business Combination and Asset Acquisition [Abstract] | |
Schedule of Company Obtained Assets and Liabilities | As part of the recapitalization, the Company obtained the assets and liabilities listed below: Cash and cash equivalents $ 69,738 Other current assets 2,473 Accrued liabilities (616 ) Net assets acquired $ 71,595 |
Short-Term Investments (Tables)
Short-Term Investments (Tables) | 9 Months Ended | 12 Months Ended |
Sep. 30, 2023 | Dec. 31, 2022 | |
Short-Term Investments [Abstract] | ||
Schedule of short-term investments | The following table provides a summary of short-term investments: September 30, 2023 Amortized Gross Gross Fair Value Available-for-sale, U.S. treasury securities $ 25,656 $ 2 $ (1 ) $ 25,657 U.S. government agency securities 6,930 2 (1 ) 6,931 Total available-for-sale, $ 32,586 $ 4 $ (2 ) $ 32,588 December 31, 2022 Amortized Gross Gross Fair Available-for-sale, U.S. treasury securities $ 47,630 $ 3 $ (122 ) $ 47,511 U.S. government agency securities 12,656 — (42 ) 12,614 Total available-for-sale, $ 60,286 $ 3 $ (164 ) $ 60,125 | The table below provides a summary of short-term investments (in thousands) as of December 31, 2022. There were no short-term investments as of December 31, 2021. December 31, 2022 Amortized Gross Gross Fair Available-for-sale, U.S. treasury securities $ 47,630 $ 3 $ (122 ) $ 47,511 U.S. government agency securities 12,656 — (42 ) 12,614 Total available-for-sale, $ 60,286 $ 3 $ (164 ) $ 60,125 |
Prepaid Expenses and Other Cu_2
Prepaid Expenses and Other Current Assets (Tables) | 9 Months Ended | 12 Months Ended |
Sep. 30, 2023 | Dec. 31, 2022 | |
Prepaid Expense and Other Assets, Current [Abstract] | ||
Summary of Prepaid Expenses and Other Current Assets | The following table provides a summary of prepaid expenses and other current assets: September 30, December 31, Prepaid materials, supplies and research and development services $ 337 $ 820 Prepaid subscriptions, software and other administrative services 475 53 Prepaid insurance 20 32 Prepaid expenses and other current assets $ 832 $ 905 | The following table provides a summary of prepaid expenses and other current assets (in thousands): December 31, 2022 2021 Prepaid materials, supplies and services $ 820 $ 243 Prepaid insurance 32 21 Other 53 10 Prepaid expenses and other current assets $ 905 $ 274 |
Property and Equipment (Tables)
Property and Equipment (Tables) | 9 Months Ended | 12 Months Ended |
Sep. 30, 2023 | Dec. 31, 2022 | |
Property, Plant and Equipment [Abstract] | ||
Schedule of Property and Equipment, Net | The following table provides a summary of property and equipment: September 30, December 31, Computer equipment $ 231 $ 131 Furniture and fixtures 41 41 Subtotal 272 172 Less: accumulated depreciation (77 ) (30 ) Property and equipment, net $ 195 $ 142 | The following table provides a summary of property and equipment (in thousands): December 31, 2022 2021 Computer equipment $ 131 $ — Furniture and fixtures 41 — Construction-in-process — 33 Subtotal 172 33 Less: accumulated depreciation (30 ) — Property and equipment, net $ 142 $ 33 |
Fair Value of Financial Instr_2
Fair Value of Financial Instruments (Tables) | 9 Months Ended | 12 Months Ended |
Sep. 30, 2023 | Dec. 31, 2022 | |
Fair Value Disclosures [Abstract] | ||
Schedule of Financial Assets Measured at Fair Value on Recurring Basis | The following table provides a summary of financial assets measured at fair value on a recurring basis: Description Fair Value at Level 1 Level 2 Level 3 Recurring Assets: Cash equivalents: Money market funds $ 154,549 $ 154,549 $ — $ — Short-term investments: U.S. treasury securities 25,657 25,657 — — U.S. government agency securities 6,931 — 6,931 — Total assets measured at fair value $ 187,137 $ 180,206 $ 6,931 $ — Description Fair Value at Level 1 Level 2 Level 3 Recurring Assets: Cash equivalents: Money market funds $ 11,846 $ 11,846 $ — $ — U.S. government agency securities 1,999 — 1,999 — Short-term investments: U.S. treasury securities 20,775 20,775 — — U.S. government agency securities 39,350 26,736 12,614 — Total assets measured at fair value $ 73,970 $ 59,357 $ 14,613 $ — | The following table provides a summary of financial assets measured at fair value on a recurring basis (in thousands): Description Fair Value at Level 1 Level 2 Level 3 Recurring Assets: Cash equivalents: Money market fund $ 11,846 $ 11,846 $ — $ — U.S. government agency securities 1,999 — 1,999 — Short-term investments: U.S. treasury securities 20,775 20,775 — — U.S. government agency securities 39,350 26,736 12,614 — Total assets measured at fair value $ 73,970 $ 59,357 $ 14,613 $ — Description Fair Value at Level 1 Level 2 Level 3 Recurring Assets: Cash equivalents: Money market fund $ 7,675 $ 7,675 $ — $ — Total assets measured at fair value $ 7,675 $ 7,675 $ — $ — |
Accrued Expenses (Tables)
Accrued Expenses (Tables) | 9 Months Ended | 12 Months Ended |
Sep. 30, 2023 | Dec. 31, 2022 | |
Schedule of Accrued Expenses | The following table provides a summary of accrued expenses: September 30, December 31, Accrued external research and development $ 1,001 $ 4,329 Accrued compensation 4,429 2,084 Accrued issuance costs in connection with pre-closing 4,200 — Accrued transaction costs related to reverse recapitalization 419 — Accrued professional fees 667 162 Other accrued expenses 481 33 Accrued expenses $ 11,197 $ 6,608 | The following table provides a summary of accrued expenses (in thousands): December 31, 2022 2021 Accrued external research and development $ 4,329 $ 3,560 Accrued compensation 2,084 207 Accrued professional fees and other 195 226 Accrued expenses $ 6,608 $ 3,993 |
Leases (Tables)
Leases (Tables) | 9 Months Ended | 12 Months Ended |
Sep. 30, 2023 | Dec. 31, 2022 | |
Leases [Abstract] | ||
Summary of the Components of Lease Costs and Rent | The following table provides a summary of the components of lease costs and rent: Three Months Nine Months 2023 2022 2023 2022 Operating lease cost $ 88 $ 66 $ 263 $ 110 Variable lease cost 7 1 20 4 Short-term lease cost — 6 — 34 Total operating lease costs $ 95 $ 73 $ 283 $ 148 | The following table provides a summary of the components of lease costs and rent (in thousands): Years Ended 2022 2021 Operating lease cost $ 198 $ — Variable lease cost 4 — Short-term lease cost 34 17 Total operating lease costs $ 236 $ 17 |
Schedule of Maturities of Operating Lease Liabilities | Maturities of operating lease liabilities, which do not include short-term leases, as of September 30, 2023, are as follows: 2023 (remaining 3 months) $ 102 2024 417 2025 222 Total undiscounted operating lease payments 741 Less: imputed interest (71 ) Present value of operating lease liabilities $ 670 Balance sheet classification: Current portion of lease liabilities $ 413 Long-term lease liabilities 257 Total operating lease liabilities $ 670 | Maturities of operating lease liabilities, which do not include short-term leases, as of December 31, 2022, are as follows (in thousands): 2023 $ 351 2024 365 2025 188 Total undiscounted operating lease payments 904 Less: imputed interest (116 ) Present value of operating lease liabilities $ 788 Balance sheet classification: Current portion of lease liabilities $ 350 Long-term lease liabilities 438 Total operating lease liabilities $ 788 |
Income Taxes (Tables)
Income Taxes (Tables) | 12 Months Ended |
Dec. 31, 2022 | |
Schedule of Reconciliation of U.S. Federal Statutory Rate to Effective Tax Rate | A reconciliation of the U.S. federal statutory income tax rate to the Company’s effective income tax rate is as follows: Years Ended 2022 2021 Federal statutory income tax rate 21.0 % 21.0 % State taxes, net of federal benefit 2.2 % 6.3 % Research tax credits 2.2 % 2.5 % Other -3.0 % -0.1 % Increase in deferred tax asset valuation allowance -22.4 % -29.7 % Effective income tax rate 0.0 % 0.0 % |
Company's Deferred Tax Assets | The following table provides a summary of net deferred tax assets (in thousands): December 31, 2022 2021 Deferred tax assets: Net operating loss carryforwards $ 5,383 $ 4,651 Tax credit carryforwards 1,120 483 Capitalized research and development costs 4,315 — Accrued expenses 484 57 Share-based compensation 273 4 Lease liabilities 183 — Organizational costs 4 5 Gross deferred tax assets 11,762 5,200 Valuation allowance (11,566 ) (5,194 ) Total deferred tax assets 196 6 Deferred tax liabilities: Right-of-use (189 ) — Prepaid expenses (7 ) (6 ) Net deferred tax assets $ — $ — |
Changes in Deferred Tax Asset Valuation Allowance | During the year ended December 31, 2022, capitalized research and development expenses increased pursuant to Section 174 of the Internal Revenue Code of 1986, as amended (the “Code”). The changes in the valuation allowance for the years ended December 31, 2022 and 2021 and were as follows (in thousands): Years Ended 2022 2021 Valuation allowance as of beginning of year $ 5,194 $ 1,307 Net increases recorded to income tax provision 6,372 3,887 Valuation allowance as of end of year $ 11,566 $ 5,194 |
Common Stock (Tables)
Common Stock (Tables) | 9 Months Ended |
Sep. 30, 2023 | |
Equity [Abstract] | |
Schedule of Common Stock Shares Reserved for Future Issuance | The Company had the following shares of Company common stock reserved for future issuance as of September 30, 2023 and December 31, 2022: As of As of Conversion of convertible preferred stock — 7,269,183 Issuance of common stock upon exercise of stock options 1,772,179 1,273,454 Equity awards available for grant under stock awards 767,454 414,679 Shares available for issuance under the Employee Stock Purchase Plan 37,078 — Issuance of common stock upon exercise of warrants 214,997 4,677 Total common stock reserved for future issuance 2,791,708 8,961,993 |
Preferred Stock and Convertib_2
Preferred Stock and Convertible Preferred Stock (Tables) | 9 Months Ended |
Sep. 30, 2023 | |
Stockholders' Equity Note [Abstract] | |
Schedule of Preferred Stock Activity | The authorized, issued and outstanding shares of the convertible preferred stock and liquidation preferences of Former Dianthus as of December 31, 2022 were as follows: Issued Authorized Shares Per Share Aggregate Proceeds Series Seed 1 Convertible Preferred Stock July 2019, April 2020 and December 2020 6,500,000 6,500,000 $ 1.000 $ 6,500 $ 6,436 Series Seed 2 Convertible Preferred Stock May 2021 3,829,266 3,829,265 $ 3.9172 15,000 14,912 Series A Convertible Preferred Stock April 2022 23,007,017 23,007,017 $ 4.3465 100,000 96,676 Total Convertible Preferred Stock 33,336,283 33,336,282 $ 121,500 $ 118,024 |
Stock-Based Compensation (Table
Stock-Based Compensation (Tables) | 9 Months Ended | 12 Months Ended |
Sep. 30, 2023 | Dec. 31, 2022 | |
Share-Based Payment Arrangement [Abstract] | ||
Schedule of Stock Option Activity | The following table summarizes stock option activity for the nine months ended September 30, 2023: Number of Weighted Weighted Aggregate (in years) Balance at January 1, 2023 529,773 $ 94.59 8.2 $ — Assumption of options in connection with the Reverse Merger 1,273,454 7.95 177 Options granted, fair value of $10.86 per share 440,041 12.31 159 Options exercised (2,798 ) 1.66 46 Options forfeited (468,291 ) 68.14 397 Balance at September 30, 2023 1,772,179 $ 19.04 8.0 $ 7,763 Exercisable options at September 30, 2023 699,237 $ 33.25 6.5 $ 2,949 Unvested options at September 30, 2023 1,072,942 $ 9.78 8.9 $ 4,814 | The following table summarizes stock option activity: Number of Weighted Weighted Aggregate (in years) (in thousands) Balance at January 1, 2021 — $ — $ — Granted, fair value of $4.31 per share 248,603 5.92 Balance at December 31, 2021 248,603 5.92 9.7 194 Granted, fair value of $6.24 per share 1,031,567 8.44 Forfeited (6,716 ) 7.55 Balance at December 31, 2022 1,273,454 $ 7.95 9.3 $ 621 Exercisable options at December 31, 2022 181,171 $ 7.18 9.1 $ 229 Unvested options at December 31, 2022 1,092,283 $ 8.08 9.4 $ 392 |
Schedule of Grant-Date Fair Value of Stock Options Issued, Presented on a Weighted Average Basis | The table below summarizes the assumptions used to determine the grant-date fair value of stock options issued, presented on a weighted average basis during the nine months ended September 30, 2023 and 2022. Nine Months Nine Months Risk-free interest rate 3.9 % 3.1 % Expected term (in years) 6.0 5.9 Expected volatility 86.4 % 87.3 % Expected dividend yield 0.0 % 0.0 % | The following table summarizes the assumptions used to determine the grant-date fair value of stock options granted, presented on a weighted average basis: Years Ended December 31, 2022 2021 Risk-free interest rate 3.08 % 1.20 % Expected term (in years) 5.9 6.1 Expected volatility 87.28 % 87.67 % Expected dividend yield 0 % 0 % |
Schedule of Activity Relating to Restricted Stock Units | The following table summarizes restricted stock unit activity for the nine months ended September 30, 2023: Number of Weighted average Balance at January 1, 2023 16,084 $ 70.09 Restricted share units granted 7,696 8.80 Restricted share units vested (6,495 ) 68.96 Restricted share units forfeited (17,285 ) 43.22 Balance at September 30, 2023 — $ — | |
Schedule of Stock Based Compensation Expense | The following table provides a summary of stock-based compensation expense related to stock options, restricted stock units, restricted stock, and warrants: Three Months Nine Months Ended 2023 2022 2023 2022 Research and development $ 379 $ 144 $ 711 $ 256 General and administrative 800 517 1,463 749 Total stock-based compensation expense $ 1,179 $ 661 $ 2,174 $ 1,005 | The following table provides a summary of stock-based compensation expense related to stock options, restricted stock, and warrants (in thousands): Years Ended 2022 2021 Research and development $ 416 $ 19 General and administrative 1,102 44 Total stock-based compensation expense $ 1,518 $ 63 |
Schedule of assumptions used to determine the fair value of warrant | The weighted average assumptions used to determine the fair value of the warrants were as follows: Year Ended Risk-free interest rate 1.14 % Expected term (in years) 6.1 Expected volatility 82.80 % Expected dividend yield 0 % |
Net Loss Per Share (Tables)
Net Loss Per Share (Tables) | 9 Months Ended | 12 Months Ended |
Sep. 30, 2023 | Dec. 31, 2022 | |
Earnings Per Share [Abstract] | ||
Schedule of Basic and diluted net loss per common share | Basic and diluted net loss per common share were calculated as follows: Three Months Ended Nine Months Ended 2023 2022 2023 2022 Numerator: Net loss $ (14,763 ) $ (7,784 ) $ (32,992 ) $ (18,360 ) Denominator: Weighted-average common shares outstanding 3,907,075 875,279 1,896,983 875,279 Less: weighted-average unvested restricted shares of common stock (189 ) (952 ) (378 ) (1,141 ) Weighted-average shares used to compute net loss per common share, basic and diluted 3,906,886 874,327 1,896,605 874,138 Net loss per share attributable to common stockholders, basic and diluted $ (3.78 ) $ (8.90 ) $ (17.40 ) $ (21.00 ) | Basic and diluted net loss per common share were calculated as follows (in thousands, except share and per share data): Years Ended 2022 2021 Numerator: Net loss $ (28,476 ) $ (13,109 ) Denominator: Weighted-average common shares outstanding 875,279 875,279 Less: weighted-average unvested restricted shares of common stock (1,045 ) (1,808 ) Weighted-average shares used to compute net loss per common share, basic and diluted 874,234 873,471 Net loss per share attributable to common stockholders, basic and diluted $ (32.57 ) (15.01 ) |
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share | The following potential dilutive securities, presented on an as converted basis, were excluded from the calculation of net loss per share due to their anti-dilutive effect: Three Months Ended Nine Months Ended 2023 2022 2023 2022 Convertible preferred stock (as converted) — 7,269,183 — 7,269,183 Stock options outstanding 1,772,179 1,253,415 1,772,179 1,253,415 Unvested restricted shares of common stock 63 826 63 826 Warrants for the purchase of common stock 214,997 4,677 214,997 4,677 Total 1,987,239 8,528,101 1,987,239 8,528,101 | The following potential dilutive securities, presented on an as converted basis, were excluded from the calculation of net loss per share due to their anti-dilutive effect: Years Ended December 31, 2022 2021 Convertible preferred stock (as converted) 7,269,183 2,252,357 Stock options outstanding 1,273,454 248,603 Unvested restricted shares of common stock 635 1,398 Warrants for the purchase of common stock 4,677 4,677 Total 8,547,949 2,507,035 |
Organization, Description of _2
Organization, Description of Business and Liquidity - Additional Information (Detail) $ / shares in Units, $ in Thousands | 3 Months Ended | 9 Months Ended | 12 Months Ended | ||||||||||
Sep. 11, 2023 USD ($) $ / shares shares | Sep. 30, 2023 USD ($) shares | Jun. 30, 2023 USD ($) | Mar. 31, 2023 USD ($) | Sep. 30, 2022 USD ($) | Jun. 30, 2022 USD ($) | Mar. 31, 2022 USD ($) | Sep. 30, 2023 USD ($) shares | Sep. 30, 2022 USD ($) | Dec. 31, 2022 USD ($) shares | Dec. 31, 2021 USD ($) shares | May 02, 2023 USD ($) | Dec. 31, 2020 shares | |
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items] | |||||||||||||
Reverse stock split description | Immediately prior to the effective time of the Reverse Merger, the Company effected a 1-for-16 reverse stock split of its common stock (the “Reverse Stock Split”). Unless noted otherwise, all references herein to share and per share amounts reflect the Reverse Stock Split. | ||||||||||||
Net loss | $ | $ (14,763) | $ (11,140) | $ (7,089) | $ (7,784) | $ (5,695) | $ (4,881) | $ (32,992) | $ (18,360) | $ (28,476) | $ (13,109) | |||
Accumulated deficit | $ | $ (78,860) | $ (78,900) | $ (78,860) | $ (78,900) | $ (45,868) | $ (17,392) | |||||||
Common stock, Shares issued | 11,021,248 | 14,817,762 | 14,817,762 | 875,279 | 875,279 | ||||||||
Exchange ratio of reverse merger | 0.2181 | ||||||||||||
Shares of common stock issued in pre-closing financing | 2,873,988 | ||||||||||||
Shares pre-funded warrants to purchase | 210,320 | ||||||||||||
Pre-funded warrants exercisable | 210,320 | ||||||||||||
Prefunded warrants price per share | $ / shares | $ 23.34 | ||||||||||||
Common stock price per share | $ / shares | $ 23.34 | ||||||||||||
Proceeds from pre-closing financing | $ | $ 72,000 | ||||||||||||
Subsequent Event [Member] | |||||||||||||
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items] | |||||||||||||
Common stock, Shares issued | 11,021,248 | ||||||||||||
Exchange ratio of reverse merger | 0.2181 | ||||||||||||
Proceeds from pre-closing financing | $ | $ 72,000 | ||||||||||||
Common Stock [Member] | |||||||||||||
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items] | |||||||||||||
Common stock, Shares issued | 14,817,762 | 14,817,762 | 875,279 | ||||||||||
Common stock, Shares outstanding | 14,817,762 | 875,279 | 875,279 | 875,279 | |||||||||
Common Stock [Member] | Subsequent Event [Member] | |||||||||||||
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items] | |||||||||||||
Common stock, Shares outstanding | 14,817,762 |
Summary of Significant Accoun_4
Summary of Significant Accounting Policies - Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share (Detail) - shares | 3 Months Ended | 9 Months Ended | 12 Months Ended | |||
Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022 | Dec. 31, 2022 | Dec. 31, 2021 | |
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] | ||||||
Anti-dilutive securities excluded from computation of earnings per share, amount | 1,987,239 | 8,528,101 | 1,987,239 | 8,528,101 | 8,547,949 | 2,507,035 |
Stock Option | ||||||
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] | ||||||
Anti-dilutive securities excluded from computation of earnings per share, amount | 1,772,179 | 1,253,415 | 1,772,179 | 1,253,415 | 1,273,454 | 248,603 |
Restricted Stock | ||||||
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] | ||||||
Anti-dilutive securities excluded from computation of earnings per share, amount | 63 | 826 | 63 | 826 | 635 | 1,398 |
Summary of Significant Accoun_5
Summary of Significant Accounting Policies - Additional Information (Detail) $ in Thousands | 3 Months Ended | 9 Months Ended | 12 Months Ended | ||
Sep. 30, 2023 USD ($) | Sep. 30, 2023 USD ($) | Dec. 31, 2022 USD ($) OperatingSegments | Dec. 31, 2022 USD ($) ReportingSegments | Dec. 31, 2021 USD ($) | |
Summary Of Significant Accounting Policies [Line Items] | |||||
Credit losses recorded | $ 0 | $ 0 | |||
Allowance for doubtful accounts | 0 | 0 | $ 0 | $ 0 | |
Financial lease liability | 0 | 0 | |||
Unrecognized tax benefits | $ 0 | $ 0 | $ 0 | $ 0 | $ 0 |
Number of operating segments | 1 | 1 | |||
Computer Equipment [Member] | |||||
Summary Of Significant Accounting Policies [Line Items] | |||||
Property plant and equipment useful lives | 3 years | 3 years | |||
Furniture and Fixtures [Member] | |||||
Summary Of Significant Accounting Policies [Line Items] | |||||
Property plant and equipment useful lives | 5 years | 5 years |
Reverse Merger - Schedule of Co
Reverse Merger - Schedule of Company Obtained Assets and Liabilities (Detail) $ in Thousands | Sep. 11, 2023 USD ($) |
Business Acquisition [Line Items] | |
Cash and cash equivalents | $ 69,738 |
Other current assets | 2,473 |
Accrued liabilities | (616) |
Net assets acquired | $ 71,595 |
Reverse Merger - Additional Inf
Reverse Merger - Additional Information (Detail) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended | 12 Months Ended | ||||
Sep. 11, 2023 | Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022 | Dec. 31, 2022 | Dec. 31, 2021 | |
Business Acquisition [Line Items] | |||||||
Stock based compensation expense | $ 1,179 | $ 661 | $ 2,174 | $ 1,005 | $ 1,518 | $ 63 | |
Research and development | 7,960 | 7,218 | 24,060 | 19,548 | 29,379 | 12,606 | |
General and administrative | 8,723 | $ 2,209 | 13,527 | $ 4,706 | $ 6,743 | $ 1,956 | |
Transaction costs | 3,964 | ||||||
Dianthus [Member] | |||||||
Business Acquisition [Line Items] | |||||||
Stock based compensation expense | $ 500 | ||||||
Research and development | 200 | 200 | |||||
General and administrative | 300 | 300 | |||||
Transaction costs | $ 4,000 | $ 4,000 |
Short-Term Investments - Schedu
Short-Term Investments - Schedule of Short-term Investments (Detail) - USD ($) $ in Thousands | Sep. 30, 2023 | Dec. 31, 2022 |
Debt Securities, Available-for-Sale [Line Items] | ||
Amortized Cost | $ 32,586 | $ 60,286 |
Gross Unrealized Gain | 4 | 3 |
Gross Unrealized Loss | (2) | (164) |
Fair Value | 32,588 | 60,125 |
U.S. Treasury Securities | ||
Debt Securities, Available-for-Sale [Line Items] | ||
Amortized Cost | 25,656 | 47,630 |
Gross Unrealized Gain | 2 | 3 |
Gross Unrealized Loss | (1) | (122) |
Fair Value | 25,657 | 47,511 |
U.S. Government Agency Securities | ||
Debt Securities, Available-for-Sale [Line Items] | ||
Amortized Cost | 6,930 | 12,656 |
Gross Unrealized Gain | 2 | 0 |
Gross Unrealized Loss | (1) | (42) |
Fair Value | $ 6,931 | $ 12,614 |
Prepaid Expenses and Other Cu_3
Prepaid Expenses and Other Current Assets - Summary of Prepaid Expenses and Other Current Assets (Detail) - USD ($) $ in Thousands | Sep. 30, 2023 | Dec. 31, 2022 | Dec. 31, 2021 |
Prepaid Expense and Other Assets, Current [Abstract] | |||
Prepaid materials, supplies and services | $ 337 | $ 820 | $ 243 |
Prepaid subscriptions, software and other administrative services | 475 | 53 | |
Prepaid Insurance | 20 | 32 | 21 |
Other | 53 | 10 | |
Prepaid expenses and other current assets | $ 832 | $ 905 | $ 274 |
Property and Equipment - Schedu
Property and Equipment - Schedule of Property and Equipment, Net (Detail) - USD ($) $ in Thousands | Sep. 30, 2023 | Dec. 31, 2022 | Dec. 31, 2021 |
Property, Plant and Equipment [Line Items] | |||
Property and equipment, gross | $ 272 | $ 172 | $ 33 |
Less: accumulated depreciation | (77) | (30) | 0 |
Property, Plant and Equipment, Net, Total | 195 | 142 | 33 |
Computer Equipment [Member] | |||
Property, Plant and Equipment [Line Items] | |||
Property and equipment, gross | 231 | 131 | 0 |
Furniture and Fixtures [Member] | |||
Property, Plant and Equipment [Line Items] | |||
Property and equipment, gross | $ 41 | 41 | 0 |
Construction in Progress [Member] | |||
Property, Plant and Equipment [Line Items] | |||
Property and equipment, gross | $ 0 | $ 33 |
Property and Equipment - Additi
Property and Equipment - Additional Information (Detail) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended | 12 Months Ended | |||
Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022 | Dec. 31, 2022 | Dec. 31, 2021 | |
Property, Plant and Equipment [Abstract] | ||||||
Depreciation Expense | $ 19 | $ 6 | $ 47 | $ 19 | $ 30 | $ 0 |
Fair Value of Financial Instr_3
Fair Value of Financial Instruments - Schedule of Financial Assets Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands | Sep. 30, 2023 | Dec. 31, 2022 | Dec. 31, 2021 |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | |||
Short-term investments | $ 32,588 | $ 60,125 | |
Fair Value on Recurring Basis | |||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | |||
Total assets measured at fair value | 187,137 | 73,970 | $ 7,675 |
Level 1 | Fair Value on Recurring Basis | |||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | |||
Total assets measured at fair value | 180,206 | 59,357 | 7,675 |
Level 2 | Fair Value on Recurring Basis | |||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | |||
Total assets measured at fair value | 6,931 | 14,613 | 0 |
Money Market Funds | Fair Value on Recurring Basis | |||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | |||
Cash equivalents | 154,549 | 11,846 | 7,675 |
Money Market Funds | Level 1 | Fair Value on Recurring Basis | |||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | |||
Cash equivalents | 154,549 | 11,846 | $ 7,675 |
U.S. Treasury Securities | |||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | |||
Short-term investments | 25,657 | 47,511 | |
U.S. Treasury Securities | Fair Value on Recurring Basis | |||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | |||
Short-term investments | 25,657 | 20,775 | |
U.S. Treasury Securities | Level 1 | Fair Value on Recurring Basis | |||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | |||
Short-term investments | 25,657 | 20,775 | |
U.S. Government Agency Securities | |||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | |||
Short-term investments | 6,931 | 12,614 | |
U.S. Government Agency Securities | Fair Value on Recurring Basis | |||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | |||
Cash equivalents | 1,999 | ||
Short-term investments | 6,931 | 39,350 | |
U.S. Government Agency Securities | Level 1 | Fair Value on Recurring Basis | |||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | |||
Short-term investments | 26,736 | ||
U.S. Government Agency Securities | Level 2 | Fair Value on Recurring Basis | |||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | |||
Cash equivalents | 1,999 | ||
Short-term investments | $ 6,931 | $ 12,614 |
Fair Value of Financial Instr_4
Fair Value of Financial Instruments - Additional Information (Detail) - USD ($) $ in Thousands | 9 Months Ended | 12 Months Ended |
Sep. 30, 2023 | Dec. 31, 2022 | |
Fair Value Disclosures [Abstract] | ||
Fair Value on Recurring Basis Level 1 | $ 0 | $ 0 |
Fair Value on Recurring Basis Level 2 | 0 | |
Fair Value on Recurring Basis Level 3 | $ 0 |
Accrued Expenses - Schedule of
Accrued Expenses - Schedule of Accrued Expenses (Detail) - USD ($) $ in Thousands | Sep. 30, 2023 | Dec. 31, 2022 | Dec. 31, 2021 |
Payables and Accruals [Abstract] | |||
Accrued external research and development | $ 1,001 | $ 4,329 | $ 3,560 |
Accrued compensation | 4,429 | 2,084 | 207 |
Accrued issuance costs in connection with pre-closing financing | 4,200 | 0 | |
Accrued transaction costs related to reverse recapitalization | 419 | 0 | |
Accrued professional fees and other | 195 | ||
Accrued professional fees | 667 | 162 | 226 |
Other accrued expenses | 481 | 33 | |
Accrued expenses | $ 11,197 | $ 6,608 | $ 3,993 |
Leases - Additional Information
Leases - Additional Information (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended | 12 Months Ended | |||
Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022 | Dec. 31, 2022 | Dec. 31, 2021 | |
Leases [Line Items] | ||||||
Property sublease, description | The Company leases space under operating leases for administrative offices in New York, New York, and Waltham, Massachusetts and wet laboratory space in Watertown, Massachusetts. The Company also leased office space under operating leases, which had a non-cancelable lease term of less than one year and, therefore, management elected the practical expedient to exclude these short-term leases from right-of-use assets and lease liabilities. | The Company leases space under operating leases for administrative offices in New York, New York and Waltham, Massachusetts. The Company also leased office space under operating leases, which had a non-cancelable lease term of less than one year and, therefore, management elected the practical expedient to exclude these short-term leases from right-of-use assets and lease liabilities. | ||||
Operating lease costs | $ 95 | $ 73 | $ 283 | $ 148 | $ 236 | $ 17 |
Weighted-Average remaining lease term | 22 months | 22 months | 30 months | |||
Weighted-average discount rate - operating lease | 10.60% | 10.60% | 10.30% | |||
General and Administrative Expenses [Member] | ||||||
Leases [Line Items] | ||||||
Operating lease costs | $ 95 | $ 73 | $ 283 | $ 148 |
Leases - Summary of the Compone
Leases - Summary of the Components of Lease Costs and Rent (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended | 12 Months Ended | |||
Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022 | Dec. 31, 2022 | Dec. 31, 2021 | |
Lease, Cost [Abstract] | ||||||
Operating lease cost | $ 88 | $ 66 | $ 263 | $ 110 | $ 198 | $ 0 |
Variable lease cost | 7 | 1 | 20 | 4 | 4 | 0 |
Short-term lease cost | 0 | 6 | 0 | 34 | 34 | 17 |
Total operating lease costs | $ 95 | $ 73 | $ 283 | $ 148 | $ 236 | $ 17 |
Leases - Schedule of Maturities
Leases - Schedule of Maturities of Operating Lease Liabilities (Details) - USD ($) $ in Thousands | Sep. 30, 2023 | Dec. 31, 2022 | Dec. 31, 2021 |
Leases [Abstract] | |||
2023 (remaining 3 months) | $ 102 | ||
2023 | 417 | $ 351 | |
2024 | 222 | 365 | |
2025 | 188 | ||
Total undiscounted operating lease payments | 741 | 904 | |
Less: imputed interest | (71) | (116) | |
Present value of operating lease liabilities | 670 | 788 | |
Current portion of lease liabilities | 413 | 350 | $ 0 |
Long-term lease liabilities | 257 | 438 | $ 0 |
Operating Lease, Liability | $ 670 | $ 788 |
Convertible Preferred Stock - A
Convertible Preferred Stock - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands | 1 Months Ended | 12 Months Ended | |||||||||
Apr. 22, 2020 | Jul. 19, 2019 | Apr. 30, 2022 | May 31, 2021 | Dec. 31, 2020 | Dec. 31, 2022 | Dec. 31, 2021 | Sep. 30, 2023 | Apr. 01, 2022 | May 01, 2021 | Dec. 01, 2020 | |
Disclosure In Entirety Of Redeemable Convertible Preferred Stock [Line Items] | |||||||||||
Preferred stock, shares authorized | 33,336,283 | 10,329,266 | 10,000,000 | ||||||||
Common stock minimum issue price per share for conversion of temporary equity into permanent equity | $ 8.693 | ||||||||||
Minimum gross proceeds from the issuance of common stock for conversion of temporary equity into permanent equity. | $ 40,000 | ||||||||||
Preferred stock, par value | $ 0.0001 | $ 0.0001 | |||||||||
Series seed one redeemable convertible preferred stock [member] | |||||||||||
Disclosure In Entirety Of Redeemable Convertible Preferred Stock [Line Items] | |||||||||||
Preferred stock, shares authorized | 6,500,000 | 6,500,000 | |||||||||
Temporary equity shares issued issue price per share | $ 1 | $ 1 | $ 1 | ||||||||
Temporary equity stock issued during the period shares new issues | 1,857,500 | 1,642,500 | 3,000,000 | ||||||||
Proceeds from redeemable convertible preferred stock | $ 1,900 | $ 1,600 | $ 3,000 | ||||||||
Temporary equity dividend per share | $ 0.06 | ||||||||||
Series seed two redeemable convertible preferred stock [member] | |||||||||||
Disclosure In Entirety Of Redeemable Convertible Preferred Stock [Line Items] | |||||||||||
Preferred stock, shares authorized | 3,829,265 | 3,829,265 | |||||||||
Temporary equity shares issued issue price per share | $ 3.9172 | ||||||||||
Temporary equity stock issued during the period shares new issues | 3,829,265 | ||||||||||
Proceeds from redeemable convertible preferred stock | $ 15,000 | $ 15,000 | |||||||||
Temporary equity dividend per share | $ 0.235 | ||||||||||
Series a redeemable convertible preferred stock [member] | |||||||||||
Disclosure In Entirety Of Redeemable Convertible Preferred Stock [Line Items] | |||||||||||
Preferred stock, shares authorized | 23,007,017 | ||||||||||
Temporary equity shares issued issue price per share | $ 4.3465 | ||||||||||
Temporary equity stock issued during the period shares new issues | 23,007,017 | ||||||||||
Proceeds from redeemable convertible preferred stock | $ 100,000 | $ 100,000 | |||||||||
Temporary equity dividend per share | $ 0.2608 |
Common Stock - Additional Infor
Common Stock - Additional Information (Details) | 9 Months Ended | |||||
Sep. 30, 2023 $ / shares shares | Sep. 11, 2023 shares | Jan. 01, 2023 shares | Dec. 31, 2022 $ / shares shares | Dec. 31, 2021 $ / shares shares | Dec. 31, 2020 shares | |
Common stock, shares authorized | 150,000,000 | 8,722,279 | 3,706,968 | |||
Common stock, Shares issued | 14,817,762 | 11,021,248 | 875,279 | 875,279 | ||
Common stock, Shares outstanding | 14,817,762 | 875,279 | 875,279 | |||
Exchange ratio of reverse merger | 0.2181 | |||||
Common stock, Par value | $ / shares | $ 0.001 | $ 0.0001 | $ 0.0001 | |||
Common stock, dividends, per share, declared | $ / shares | $ 0 | |||||
Common Stock | ||||||
Common stock, shares authorized | 150,000,000 | 9,837,322 | 8,722,279 | 3,706,968 | ||
Common stock, Shares issued | 14,817,762 | 875,279 | ||||
Common stock, Shares outstanding | 14,817,762 | 875,279 | ||||
Common stock, Shares outstanding | 14,817,762 | 875,279 | 875,279 | 875,279 | ||
Common stock, Par value | $ / shares | $ 0.001 | $ 0.0001 | ||||
Common Stock | Previously Reported | ||||||
Common stock, shares authorized | 40,000,000 | |||||
Common stock, Par value | $ / shares | $ 0.0001 |
Common Stock - Schedule of Comm
Common Stock - Schedule of Common Stock Reserved For Future Issuance (Details) - shares | Sep. 30, 2023 | Dec. 31, 2022 |
Equity [Abstract] | ||
Conversion of convertible preferred stock | 0 | 7,269,183 |
Issuance of common stock upon exercise of stock options | 1,772,179 | 1,273,454 |
Equity awards available for grant under stock awards | 767,454 | 414,679 |
Shares available for issuance under the Employee Stock Purchase Plan | 37,078 | 0 |
Issuance of common stock upon exercise of warrants | 214,997 | 4,677 |
Total common stock reserved for future issuance | 2,791,708 | 8,961,993 |
Preferred Stock and Convertib_3
Preferred Stock and Convertible Preferred Stock - Additional Information (Details) | Sep. 30, 2023 $ / shares shares | Sep. 11, 2023 shares | Dec. 31, 2022 $ / shares shares | Dec. 31, 2021 shares |
Class of Stock [Line Items] | ||||
Preferred stock, Shares authorized | 10,000,000 | 33,336,283 | 10,329,266 | |
Preferred stock, par value | $ / shares | $ 0.001 | $ 0.001 | ||
Preferred stock, Shares issued | 0 | 0 | ||
Preferred stock, Shares outstanding | 0 | 0 | ||
Shares issued upon conversion of convertible preferred stock | 7,269,183 | |||
Exchange ratio of reverse merger | 0.2181 |
Preferred Stock and Convertib_4
Preferred Stock and Convertible Preferred Stock - Schedule of Preferred Stock Activity (Details) - USD ($) $ / shares in Units, $ in Thousands | 12 Months Ended | ||
Dec. 31, 2022 | Sep. 30, 2023 | Dec. 31, 2021 | |
Class of Stock [Line Items] | |||
Preferred Stock, Shares Authorized | 33,336,283 | 10,000,000 | 10,329,266 |
Preferred Stock, Shares Issued | 0 | 0 | |
Preferred Stock, Shares Outstanding | 0 | 0 | |
Preferred Stock, Value, Issued | $ 0 | $ 0 | |
Series Seed 1 Convertible Preferred Stock | Dianthus | |||
Class of Stock [Line Items] | |||
Preferred Stock, Shares Authorized | 6,500,000 | ||
Preferred Stock, Shares Issued | 6,500,000 | ||
Preferred Stock, Shares Outstanding | 6,500,000 | ||
Preferred Stock, Liquidation Preference Per Share | $ 1 | ||
Preferred Stock, Liquidation Preference, Value | $ 6,500 | ||
Preferred Stock, Value, Issued | $ 6,436 | ||
Series Seed 1 Convertible Preferred Stock | Dianthus | First Issue | |||
Class of Stock [Line Items] | |||
Preferred Stock Issued Date | 2019-07 | ||
Series Seed 1 Convertible Preferred Stock | Dianthus | Second Issue | |||
Class of Stock [Line Items] | |||
Preferred Stock Issued Date | 2020-04 | ||
Series Seed 1 Convertible Preferred Stock | Dianthus | Third issue | |||
Class of Stock [Line Items] | |||
Preferred Stock Issued Date | 2020-12 | ||
Series Seed 2 Convertible Preferred Stock | Dianthus | |||
Class of Stock [Line Items] | |||
Preferred Stock Issued Date | 2021-05 | ||
Preferred Stock, Shares Authorized | 3,829,266 | ||
Preferred Stock, Shares Issued | 3,829,265 | ||
Preferred Stock, Shares Outstanding | 3,829,265 | ||
Preferred Stock, Liquidation Preference Per Share | $ 3.9172 | ||
Preferred Stock, Liquidation Preference, Value | $ 15,000 | ||
Preferred Stock, Value, Issued | $ 14,912 | ||
Series A Convertible Preferred Stock | Dianthus | |||
Class of Stock [Line Items] | |||
Preferred Stock Issued Date | 2022-04 | ||
Preferred Stock, Shares Authorized | 23,007,017 | ||
Preferred Stock, Shares Issued | 23,007,017 | ||
Preferred Stock, Shares Outstanding | 23,007,017 | ||
Preferred Stock, Liquidation Preference Per Share | $ 4.3465 | ||
Preferred Stock, Liquidation Preference, Value | $ 100,000 | ||
Preferred Stock, Value, Issued | $ 96,676 | ||
Convertible Preferred Stock | Dianthus | |||
Class of Stock [Line Items] | |||
Preferred Stock, Shares Authorized | 33,336,283 | ||
Preferred Stock, Shares Issued | 33,336,282 | ||
Preferred Stock, Shares Outstanding | 33,336,282 | ||
Preferred Stock, Liquidation Preference, Value | $ 121,500 | ||
Preferred Stock, Value, Issued | $ 118,024 |
Stock-Based Compensation - Addi
Stock-Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions | 1 Months Ended | 9 Months Ended | 12 Months Ended | |||||
Apr. 30, 2021 | Apr. 30, 2020 | Sep. 30, 2023 | Sep. 30, 2022 | Dec. 31, 2022 | Dec. 31, 2021 | Sep. 11, 2023 | Jul. 31, 2019 | |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||||||||
Weighted average fair value of stock options granted | $ 10.86 | $ 6.24 | $ 4.31 | |||||
Number of units unvested | 0 | 16,084 | ||||||
Number of Shares, Options vested and expected to vest as of September 30, 2023 | 181,171 | |||||||
Warrant per grant date fair value | $ 0 | $ 70.09 | ||||||
Common stock shares reserved for future issuance | 2,791,708 | 8,961,993 | ||||||
Warrant [Member] | ||||||||
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||||||||
Common stock Purchased | 4,677 | |||||||
Common stock exercise price | $ 1.65 | $ 1.65 | ||||||
Share based compensation arrangement , requisite service period | 4 years | |||||||
Restricted stock award vested percentage | 1.16% | |||||||
Vesting period | 4 years | |||||||
Vesting period | 7 years 7 months 6 days | 8 years 3 months 18 days | ||||||
Warrants issued | 4,677 | 0 | ||||||
Warrant per grant date fair value | $ 1.16 | |||||||
Share based compensation by share based award weighted average remaning vesting period | 7 months | |||||||
Restricted Stock [Member] | ||||||||
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||||||||
Common stock Purchased | 3,052 | |||||||
Common stock exercise price | $ 0.14 | |||||||
Sharebased compensation arrangement by share based payment vested commencement percentage | 2.0833% | |||||||
Restricted stock award vested percentage | 25% | |||||||
Number of units vested | 2,989 | |||||||
Number of units unvested | 63 | 635 | ||||||
Warrants issued | 0 | 0 | ||||||
Share based compensation by share based award equity instruments other than options vested and expected to vest | 2,417 | |||||||
Grant weighted average grant date fair value per share | $ 0.14 | |||||||
Common Stock Exercise Price | $ 0.14 | |||||||
Common stock purchased | 3,052 | |||||||
2018 Stock Option and Incentive Plan [Member] | ||||||||
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||||||||
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized | 1,039,611 | |||||||
Share-Based Compensation Arrangement by Share-Based Payment Award, Terms of Award | The 2018 Incentive Plan provides for the grant of incentive stock options, nonqualified stock options, stock appreciation rights, restricted stock awards, restricted stock units, unrestricted stock awards, cash-based awards, and dividend equivalent rights. In connection with the Reverse Merger, the 2018 Incentive Plan also provides for the assumption of shares remaining available for delivery under the 2019 Stock Plan (as defined below), and such shares will be available for the granting of awards under the 2018 Incentive Plan in accordance with applicable stock exchange requirements. The Company also has outstanding stock options under the Magenta Therapeutics, Inc. 2016 Stock Option and Grant Plan, as amended (the “2016 Plan”), but is no longer granting awards under the 2016 Plan. | |||||||
Shares available for issuance | 767,454 | |||||||
Total unrecognized stock-based compensation expense related to unvested share-based awards | $ 7.8 | $ 5.9 | ||||||
Period for recognition of unrecognized expense | 2 years 7 months 6 days | 3 years 2 months 12 days | ||||||
Percentage of purchase price of common stock under the ESPP | 110% | |||||||
Number of shares reserved and available for issuance increment percentage | 4% | |||||||
2018 Stock Option and Incentive Plan [Member] | Restricted Stock [Member] | Minimum [Member] | ||||||||
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||||||||
Vesting period | 12 months | |||||||
2018 Stock Option and Incentive Plan [Member] | Restricted Stock [Member] | Maximum [Member] | ||||||||
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||||||||
Vesting period | 4 years | |||||||
2018 Stock Option and Incentive Plan [Member] | Stock Options and Stock Appreciation Rights [Member] | Maximum [Member] | ||||||||
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||||||||
Term of award | 10 years | |||||||
2018 Stock Option and Incentive Plan [Member] | Certain Incentive Stock Options [Member] | Maximum [Member] | ||||||||
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||||||||
Term of award | 5 years | |||||||
2019 Employee Stock Purchase Plan [Member] | ||||||||
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||||||||
Share-Based Compensation Arrangement by Share-Based Payment Award, Terms of Award | The ESPP provides that the number of shares reserved and available for issuance under the ESPP will automatically increase each January 1 through January 1, 2029, by the lesser of (i) 1% of the number of shares issued and outstanding on the immediately preceding December 31, (ii) 1,000,000 shares and (iii) such number of shares as determined by the Company’s board of directors or its appointed administrator. | |||||||
Shares available for issuance | 37,078 | |||||||
Percentage of purchase price of common stock under the ESPP | 85% | |||||||
Common stock purchased | 0 | 3,106 | ||||||
Stock issued, price per shares | $ 15.84 | |||||||
2019 Employee Stock Purchase Plan [Member] | Minimum [Member] | ||||||||
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||||||||
Number of shares reserved and available for issuance increment percentage | 1% | |||||||
Additional number of shares reserved and available for issuance | 1,000,000 | |||||||
2019 Stock Plan [Member] | ||||||||
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||||||||
Shares available for issuance | 417,755 | |||||||
Number of Shares, Options vested and expected to vest as of September 30, 2023 | 1,486,408 | |||||||
Common stock shares reserved for future issuance | 1,691,208 | |||||||
Share based compensation by share based cumulative options issued | 1,273,454 | |||||||
2019 Stock Plan [Member] | Employee Stock Option [Member] | ||||||||
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||||||||
Percentage of purchase price of common stock under the ESPP | 100% | |||||||
2019 Stock Plan [Member] | Employee Stock Option [Member] | Cliff Vesting [Member] | ||||||||
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||||||||
Restricted stock award vested percentage | 25% | |||||||
2019 Stock Plan [Member] | Tranche One [Member] | Employee Stock Option [Member] | ||||||||
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||||||||
Percentage of the total voting power | 10% | |||||||
2019 Stock Plan [Member] | Tranche Two [Member] | Employee Stock Option [Member] | ||||||||
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||||||||
Percentage of purchase price of common stock under the ESPP | 110% |
Stock-Based Compensation - Sche
Stock-Based Compensation - Schedule of Stock Option Activity (Detail) - USD ($) $ / shares in Units, $ in Thousands | 9 Months Ended | 12 Months Ended | |
Sep. 30, 2023 | Dec. 31, 2022 | Dec. 31, 2021 | |
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] | |||
Number of Shares, Beginning Balance | 1,273,454 | 248,603 | |
Number of Shares, Granted | 1,031,567 | 248,603 | |
Number of Shares, Forfeited | (6,716) | ||
Number of Shares, Ending Balance | 1,273,454 | 248,603 | |
Number of Shares, Options exercisable as of September 30, 2023 | 181,171 | ||
Number of Shares, Options vested and expected to vest as of September 30, 2023 | 1,092,283 | ||
Weighted-Average Exercise Price, Outstanding, Beginning balance | $ 7.95 | $ 5.92 | |
Weighted-Average Exercise Price, Granted | 8.44 | $ 5.92 | |
Weighted-Average Exercise Price, Forfeited | 7.55 | ||
Weighted-Average Exercise Price, Outstanding, Ending balance | 7.95 | $ 5.92 | |
Weighted-Average Exercise Price, Options exercisable as of September 30, 2023 | 7.18 | ||
Weighted-Average Exercise Price, Options vested and expected to vest as of September 30, 2023 | $ 8.08 | ||
Weighted Average Remaining Contractual Term | 9 years 3 months 18 days | 9 years 8 months 12 days | |
Weighted Average Remaining Contractual Term, Options exercisable as of September 30, 2023 | 9 years 1 month 6 days | ||
Weighted Average Remaining Contractual Term, Options vested and expected to vest as of September 30, 2023 | 9 years 4 months 24 days | ||
Aggregate Intrinsic Value, Ending Balance | $ 621 | $ 194 | |
Aggregate Intrinsic Value, Options exercisable as of September 30, 2023 | 229 | ||
Aggregate Intrinsic Value, Options vested and expected to vest as of September 30, 2023 | $ 392 | ||
Reverse Stock Split Event [Member] | |||
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] | |||
Number of Shares, Beginning Balance | 529,773 | ||
Assumption of options in connection with the reverse merger | 1,273,454 | ||
Number of Shares, Granted | 440,041 | ||
Number of Shares, Exercised | (2,798) | ||
Number of Shares, Forfeited | (468,291) | ||
Number of Shares, Ending Balance | 1,772,179 | 529,773 | |
Number of Shares, Options exercisable as of September 30, 2023 | 699,237 | ||
Number of Shares, Options vested and expected to vest as of September 30, 2023 | 1,072,942 | ||
Weighted-Average Exercise Price, Outstanding, Beginning balance | $ 94.59 | ||
Assumption of options in connection with the reverse merger | 7.95 | ||
Weighted-Average Exercise Price, Granted | 12.31 | ||
Weighted-Average Exercise Price, Exercised | 1.66 | ||
Weighted-Average Exercise Price, Forfeited | 68.14 | ||
Weighted-Average Exercise Price, Outstanding, Ending balance | 19.04 | $ 94.59 | |
Weighted-Average Exercise Price, Options exercisable as of September 30, 2023 | 33.25 | ||
Weighted-Average Exercise Price, Options vested and expected to vest as of September 30, 2023 | $ 9.78 | ||
Weighted Average Remaining Contractual Term | 8 years | 8 years 2 months 12 days | |
Weighted Average Remaining Contractual Term, Options exercisable as of September 30, 2023 | 6 years 6 months | ||
Weighted Average Remaining Contractual Term, Options vested and expected to vest as of September 30, 2023 | 8 years 10 months 24 days | ||
Assumption of options in connection with the Reverse Merger | $ 177 | ||
Aggregate Intrinsic Value, Granted | 159 | ||
Aggregate Intrinsic Value, Exercised | 46 | ||
Aggregate Intrinsic Value, Forfeited | 397 | ||
Aggregate Intrinsic Value, Ending Balance | 7,763 | ||
Aggregate Intrinsic Value, Options exercisable as of September 30, 2023 | 2,949 | ||
Aggregate Intrinsic Value, Options vested and expected to vest as of September 30, 2023 | $ 4,814 |
Stock-Based Compensation - Sc_2
Stock-Based Compensation - Schedule of Stock Option Activity (Parenthetical) (Detail) - $ / shares | 9 Months Ended | 12 Months Ended | |
Sep. 30, 2023 | Dec. 31, 2022 | Dec. 31, 2021 | |
Share-Based Payment Arrangement [Abstract] | |||
Weighted average fair value of stock options granted | $ 10.86 | $ 6.24 | $ 4.31 |
Stock-Based Compensation - Sc_3
Stock-Based Compensation - Schedule of Grant-date Fair Value of Stock Options Issued, Presented on a Weighted Average Basis (Detail) | 9 Months Ended | 12 Months Ended | ||
Sep. 30, 2023 | Sep. 30, 2022 | Dec. 31, 2022 | Dec. 31, 2021 | |
Share-Based Payment Arrangement [Abstract] | ||||
Risk-free interest rate | 3.90% | 3.10% | 3.08% | 1.20% |
Expected term | 6 years | 5 years 10 months 24 days | 5 years 10 months 24 days | 6 years 1 month 6 days |
Expected volatility | 86.40% | 87.30% | 87.28% | 87.67% |
Expected dividend yield | 0% | 0% | 0% | 0% |
Stock-Based Compensation - Sc_4
Stock-Based Compensation - Schedule of Activity Relating to Restricted Stock Units (Detail) | 9 Months Ended |
Sep. 30, 2023 $ / shares shares | |
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] | |
Number of units outstanding, Beginning Balance | shares | 16,084 |
Number of units outstanding, Ending Balance | shares | 0 |
Weighted average grant date fair value per share, Beginning Balance | $ / shares | $ 70.09 |
Weighted average grant date fair value per share, Ending Balance | $ / shares | $ 0 |
Restricted Stock Units [Member] | |
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] | |
Number of units outstanding, Granted | shares | 7,696 |
Number of units outstanding, Vested | shares | (6,495) |
Number of units outstanding, Forfeited | shares | (17,285) |
Weighted average grant date fair value per share, Granted | $ / shares | $ 8.8 |
Weighted average grant date fair value per share, Vested | $ / shares | 68.96 |
Weighted average grant date fair value per share, Forfeited | $ / shares | $ 43.22 |
Stock-Based Compensation - Sc_5
Stock-Based Compensation - Schedule of Stock Based Compensation Expense (Detail) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended | 12 Months Ended | |||
Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022 | Dec. 31, 2022 | Dec. 31, 2021 | |
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items] | ||||||
Stock based compensation expense | $ 1,179 | $ 661 | $ 2,174 | $ 1,005 | $ 1,518 | $ 63 |
Stock-based Compensation Expense | Research and Development Expenses [Member] | ||||||
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items] | ||||||
Stock based compensation expense | 379 | 144 | 711 | 256 | 416 | 19 |
Stock-based Compensation Expense | General and Administrative Expenses [Member] | ||||||
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items] | ||||||
Stock based compensation expense | $ 800 | $ 517 | $ 1,463 | $ 749 | $ 1,102 | $ 44 |
Stock-Based Compensation - Sc_6
Stock-Based Compensation - Schedule Of Assumptions Used To Determine The Fair Value Of Warrant (Detail) | Dec. 31, 2021 yr |
Measurement Input, Risk Free Interest Rate [Member] | |
Class of Warrant or Right [Line Items] | |
Warrants and Rights Outstanding, Measurement Input | 1.14 |
Measurement Input, Expected Term [Member] | |
Class of Warrant or Right [Line Items] | |
Warrants and Rights Outstanding, Measurement Input | 6.1 |
Measurement Input, Price Volatility [Member] | |
Class of Warrant or Right [Line Items] | |
Warrants and Rights Outstanding, Measurement Input | 82.8 |
Measurement Input, Expected Dividend Rate [Member] | |
Class of Warrant or Right [Line Items] | |
Warrants and Rights Outstanding, Measurement Input | 0 |
License Revenue - Related Par_2
License Revenue - Related Party - Additional Information (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended | 9 Months Ended | 12 Months Ended | ||||
Sep. 30, 2023 | Sep. 30, 2022 | Jun. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022 | Dec. 31, 2022 | Dec. 31, 2021 | Sep. 30, 2021 | |
Related Party Transaction [Line Items] | ||||||||
License revenue—related party | $ 924 | $ 1,173 | $ 2,369 | $ 5,242 | $ 6,417 | $ 1,476 | ||
Unbilled receivable from related party | 519 | 519 | 938 | 1,007 | ||||
Deferred revenue current | 100 | 100 | 100 | 0 | ||||
Deferred revenue noncurrent | 745 | 745 | 791 | 0 | ||||
Zenas BioPharma Limited [Member] | ||||||||
Related Party Transaction [Line Items] | ||||||||
Reimbursement of development costs | $ 1,100 | |||||||
License revenue—related party | 900 | $ 1,200 | 2,400 | $ 5,200 | 6,400 | 1,500 | ||
Related party receivable | 200 | 200 | 4,700 | 500 | ||||
Unbilled receivable from related party | 500 | 500 | 900 | $ 1,000 | ||||
Deferred revenue current | 100 | 100 | 100 | |||||
Deferred revenue noncurrent | $ 700 | 700 | 800 | |||||
Zenas BioPharma Limited [Member] | Milestone [Member] | ||||||||
Related Party Transaction [Line Items] | ||||||||
Development milestones | 11,000 | |||||||
Zenas BioPharma Limited [Member] | Royalty [Member] | ||||||||
Related Party Transaction [Line Items] | ||||||||
License revenue—related party | $ 0 | $ 0 | ||||||
Zenas BioPharma Limited [Member] | Upfront Payment [Member] | ||||||||
Related Party Transaction [Line Items] | ||||||||
Upfront payments | $ 1,000 | $ 1,000 |
Income Taxes - Schedule of Reco
Income Taxes - Schedule of Reconciliation of U.S. Federal Statutory Rate to Effective Tax Rate (Detail) | 12 Months Ended | |
Dec. 31, 2022 | Dec. 31, 2021 | |
Federal statutory income tax rate | 21% | 21% |
State taxes, net of federal benefit | 2.20% | 6.30% |
Research tax credits | 2.20% | 2.50% |
Other | (3.00%) | (0.10%) |
Increase in deferred tax asset valuation allowance | (22.40%) | (29.70%) |
Effective income tax rate | 0% | 0% |
Income Taxes - Company's Deferr
Income Taxes - Company's Deferred Tax Assets (Detail) - USD ($) $ in Thousands | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020 |
Deferred Tax Assets, Gross [Abstract] | |||
Net operating loss carryforwards | $ 5,383 | $ 4,651 | |
Capitalized research and development costs | 4,315 | 0 | |
Accrued expenses | 484 | 57 | |
Share-based compensation | 273 | 4 | |
Lease liabilities | 183 | 0 | |
Organizational costs | 4 | 5 | |
Gross deferred tax assets | 11,762 | 5,200 | |
Valuation allowance | (11,566) | (5,194) | $ (1,307) |
Total deferred tax assets | 196 | 6 | |
Tax credit carryforwards | 1,120 | 483 | |
Deferred Tax Liabilities, Gross [Abstract] | |||
Right-of-use lease assets | (189) | ||
Prepaid expenses | (7) | (6) | |
Net deferred tax assets | $ 0 | $ 0 |
Income Taxes - Changes in Defer
Income Taxes - Changes in Deferred Tax Asset Valuation Allowance (Detail) - USD ($) $ in Thousands | 12 Months Ended | |
Dec. 31, 2022 | Dec. 31, 2021 | |
Valuation allowance as of beginning of year | $ 5,194 | $ 1,307 |
Net increases recorded to income tax provision | 6,372 | 3,887 |
Valuation allowance as of end of year | $ 11,566 | $ 5,194 |
Income Taxes - Additional Infor
Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands | 12 Months Ended | ||
Dec. 31, 2022 | Dec. 31, 2021 | Sep. 30, 2023 | |
Income Tax Disclosure [Line Items] | |||
Maximum percentage change in ownership interest permissible | 50% | ||
Period over which ownership change is permitted | 3 years | ||
Unrecognized tax benefits | $ 0 | $ 0 | $ 0 |
Income tax expense (benefit) | $ 0 | $ 0 | |
State and Local Jurisdiction [Member] | |||
Income Tax Disclosure [Line Items] | |||
Operating Loss Carryforward Expiration Year Start | 2038 | ||
State and Local Jurisdiction [Member] | Expirable [Member] | |||
Income Tax Disclosure [Line Items] | |||
Net operating loss carryforwards | $ 20,100 | ||
Domestic Tax Authority [Member] | |||
Income Tax Disclosure [Line Items] | |||
Net operating loss carryforwards | $ 24,500 | ||
Domestic Tax Authority [Member] | Indefinitely [Member] | |||
Income Tax Disclosure [Line Items] | |||
Percentage of taxable income eligible to be set off against net operating loss | 80% |
Net Loss Per Share - Schedule o
Net Loss Per Share - Schedule of Basic and diluted net loss per common share (Detail) - USD ($) $ / shares in Units, $ in Thousands | 3 Months Ended | 9 Months Ended | 12 Months Ended | |||||||
Sep. 30, 2023 | Jun. 30, 2023 | Mar. 31, 2023 | Sep. 30, 2022 | Jun. 30, 2022 | Mar. 31, 2022 | Sep. 30, 2023 | Sep. 30, 2022 | Dec. 31, 2022 | Dec. 31, 2021 | |
Earnings Per Share [Abstract] | ||||||||||
Net loss | $ (14,763) | $ (11,140) | $ (7,089) | $ (7,784) | $ (5,695) | $ (4,881) | $ (32,992) | $ (18,360) | $ (28,476) | $ (13,109) |
Weighted-average common shares outstanding | 3,907,075 | 875,279 | 1,896,983 | 875,279 | 875,279 | 875,279 | ||||
Less: weighted-average unvested restricted shares of common stock | (189) | (952) | (378) | (1,141) | (1,045) | (1,808) | ||||
Weighted average number of shares outstanding, basic | 3,906,886 | 874,327 | 1,896,605 | 874,138 | 874,234 | 873,471 | ||||
Weighted average number of shares outstanding, diluted | 3,906,886 | 874,327 | 1,896,605 | 874,138 | 874,234 | 873,471 | ||||
Net loss per share attributable to common stockholders, basic | $ (3.78) | $ (8.9) | $ (17.4) | $ (21) | $ (32.57) | $ (15.01) | ||||
Net loss per share attributable to common stockholders, diluted | $ (3.78) | $ (8.9) | $ (17.4) | $ (21) | $ (32.57) | $ (15.01) |
Net Loss Per Share - Schedule_2
Net Loss Per Share - Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share (Detail) - shares | 3 Months Ended | 9 Months Ended | 12 Months Ended | |||
Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022 | Dec. 31, 2022 | Dec. 31, 2021 | |
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] | ||||||
Antidilutive securities excluded from computation of earnings per share, amount | 1,987,239 | 8,528,101 | 1,987,239 | 8,528,101 | 8,547,949 | 2,507,035 |
Convertible Preferred Stock | ||||||
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] | ||||||
Antidilutive securities excluded from computation of earnings per share, amount | 0 | 7,269,183 | 0 | 7,269,183 | 7,269,183 | 2,252,357 |
Stock Option | ||||||
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] | ||||||
Antidilutive securities excluded from computation of earnings per share, amount | 1,772,179 | 1,253,415 | 1,772,179 | 1,253,415 | 1,273,454 | 248,603 |
Restricted Stock | ||||||
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] | ||||||
Antidilutive securities excluded from computation of earnings per share, amount | 63 | 826 | 63 | 826 | 635 | 1,398 |
Warrants | ||||||
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] | ||||||
Antidilutive securities excluded from computation of earnings per share, amount | 214,997 | 4,677 | 214,997 | 4,677 | 4,677 | 4,677 |
Commitments and Contingencies -
Commitments and Contingencies - Additional Information (Details) £ in Millions | 3 Months Ended | 9 Months Ended | 12 Months Ended | ||||||
Sep. 30, 2023 USD ($) | Sep. 30, 2022 USD ($) | Sep. 30, 2023 USD ($) | Sep. 30, 2022 USD ($) | Dec. 31, 2022 USD ($) | Dec. 31, 2021 USD ($) | Sep. 30, 2023 GBP (£) | Jun. 30, 2023 USD ($) | Dec. 31, 2022 GBP (£) | |
Other Commitments [Line Items] | |||||||||
Research and development expense | $ 7,960,000 | $ 7,218,000 | $ 24,060,000 | $ 19,548,000 | $ 29,379,000 | $ 12,606,000 | |||
Alloy Therapeutics Llc [Member] | |||||||||
Other Commitments [Line Items] | |||||||||
Payment of annual license fees and program fees | 100,000 | 100,000 | |||||||
Research and development expense | 50,000 | 50,000 | 100,000 | 50,000 | 500,000 | 100,000 | |||
Alloy Therapeutics Llc [Member] | Development Milestone [Member] | First Selected Antibody [Member] | Maximum [Member] | |||||||||
Other Commitments [Line Items] | |||||||||
Potential milestone payments due | 1,800,000 | 1,800,000 | 1,800,000 | ||||||
Alloy Therapeutics Llc [Member] | Development Milestone [Member] | Second Selected Antibody [Member] | Maximum [Member] | |||||||||
Other Commitments [Line Items] | |||||||||
Potential milestone payments due | 3,100,000 | 3,100,000 | 3,100,000 | ||||||
Alloy Therapeutics Llc [Member] | Commercial Milestone [Member] | First Selected Antibody [Member] | Maximum [Member] | |||||||||
Other Commitments [Line Items] | |||||||||
Potential milestone payments due | 11,000,000 | 11,000,000 | 11,000,000 | ||||||
Alloy Therapeutics Llc [Member] | Commercial Milestone [Member] | Second Selected Antibody [Member] | Maximum [Member] | |||||||||
Other Commitments [Line Items] | |||||||||
Potential milestone payments due | 15,000,000 | 15,000,000 | 15,000,000 | ||||||
Ligand Pharmaceuticals Incorporated [Member] | |||||||||
Other Commitments [Line Items] | |||||||||
Research and development expense | 100,000 | 200,000 | 100,000 | 100,000 | |||||
Ligand Pharmaceuticals Incorporated [Member] | Development Milestone [Member] | |||||||||
Other Commitments [Line Items] | |||||||||
Potential milestone payments due | 12,200,000 | 12,200,000 | 12,200,000 | ||||||
Ligand Pharmaceuticals Incorporated [Member] | Commercial Milestone [Member] | |||||||||
Other Commitments [Line Items] | |||||||||
Potential milestone payments due | $ 0 | ||||||||
IONTAS Limited [Member] | |||||||||
Other Commitments [Line Items] | |||||||||
Research and development expense | 600,000 | $ 200,000 | 2,000,000 | $ 800,000 | $ 1,700,000 | $ 2,700,000 | |||
IONTAS Limited [Member] | Development Milestone [Member] | First Development Program [Member] | |||||||||
Other Commitments [Line Items] | |||||||||
Potential milestone payments due | 3,900,000 | 3,900,000 | £ 3.1 | £ 3.1 | |||||
IONTAS Limited [Member] | Development Milestone [Member] | Second Development Program [Member] | |||||||||
Other Commitments [Line Items] | |||||||||
Potential milestone payments due | 3,100,000 | 3,100,000 | 2.5 | 2.5 | |||||
IONTAS Limited [Member] | Commercial Milestone [Member] | First Development Program [Member] | |||||||||
Other Commitments [Line Items] | |||||||||
Potential milestone payments due | $ 2,900,000 | $ 2,900,000 | £ 2.3 | £ 2.3 |
Related Party Transactions - Ad
Related Party Transactions - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands | 3 Months Ended | 9 Months Ended | 12 Months Ended | |||||||
Mar. 15, 2023 | Mar. 13, 2023 | Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022 | Dec. 31, 2022 | Dec. 31, 2021 | Sep. 11, 2023 | Dec. 31, 2020 | |
Related Party Transaction [Line Items] | ||||||||||
Common stock, Shares issued | 14,817,762 | 14,817,762 | 875,279 | 875,279 | 11,021,248 | |||||
Common stock, Par value | $ 0.001 | $ 0.001 | $ 0.0001 | $ 0.0001 | ||||||
Unbilled receivable from related party | $ 519 | $ 519 | $ 938 | $ 1,007 | ||||||
Deferred revenue current | 100 | 100 | 100 | 0 | ||||||
Deferred revenue noncurrent | $ 745 | 745 | $ 791 | $ 0 | ||||||
Aggregate principal amount | 377 | $ 0 | ||||||||
Principal and interest repaid | $ 377 | 0 | ||||||||
Viridian Llc [Member] | ||||||||||
Related Party Transaction [Line Items] | ||||||||||
Common stock, Shares issued | 872,227 | 872,227 | 872,227 | |||||||
Common stock, Par value | $ 0.09 | $ 0.09 | $ 0.09 | |||||||
Percentage of outstanding shares | 7% | 7% | 13% | 35% | ||||||
Zenas BioPharma Limited [Member] | ||||||||||
Related Party Transaction [Line Items] | ||||||||||
Common stock, Shares issued | 156,848 | |||||||||
Related party receivable | $ 200 | $ 200 | $ 4,700 | $ 500 | ||||||
Unbilled receivable from related party | 500 | 500 | 900 | $ 1,000 | ||||||
Deferred revenue current | 100 | 100 | 100 | |||||||
Deferred revenue noncurrent | $ 700 | $ 700 | $ 800 | |||||||
Zenas BioPharma Limited [Member] | Dianthus [Member] | ||||||||||
Related Party Transaction [Line Items] | ||||||||||
Aggregate principal amount | $ 400 | |||||||||
Interest rate | 4.50% | |||||||||
Zenas BioPharma Limited [Member] | Tellus Bioventures Llc [Member] | ||||||||||
Related Party Transaction [Line Items] | ||||||||||
Percentage of outstanding shares | 10% | 10% | 17% | 42% | ||||||
Zenas BioPharma Limited [Member] | Fairmount Funds [Member] | ||||||||||
Related Party Transaction [Line Items] | ||||||||||
Percentage of outstanding shares | 13% | 13% | 14% | 13% | ||||||
Principal and interest repaid | $ 400 | |||||||||
License Revenue [Member] | Zenas BioPharma Limited [Member] | ||||||||||
Related Party Transaction [Line Items] | ||||||||||
Revenues | $ 900 | $ 1,200 | $ 2,400 | $ 5,200 | $ 6,400 | $ 1,500 |
Subsequent Events - Additional
Subsequent Events - Additional Information (Detail) - shares | 4 Months Ended | 12 Months Ended | |
May 15, 2023 | Dec. 31, 2022 | Dec. 31, 2021 | |
Subsequent Event [Line Items] | |||
Share based compensation by share based award options issued during the period | 1,031,567 | 248,603 | |
2019 Stock Plan [Member] | |||
Subsequent Event [Line Items] | |||
Share based compensation by share based award options issued during the period | 209,046 |