Sera Prognostics (SERA) 10-Q 7 Aug 24 2024 Q2 Quarterly report Financial data

Cover

Cover - shares	6 Months Ended
	Jun. 30, 2024	Aug. 02, 2024
Document Information [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2024
Document Transition Report	false
Entity File Number	001-40606
Entity Registrant Name	SERA PROGNOSTICS, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	26-1911522
Entity Address, Address Line One	2749 East Parleys Way
Entity Address, Address Line Two	Suite 200
Entity Address, City or Town	Salt Lake City
Entity Address, State or Province	UT
Entity Address, Postal Zip Code	84109
City Area Code	801
Local Phone Number	990-0520
Title of 12(b) Security	Class A Common Stock, $0.0001 par value per share
Trading Symbol	SERA
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Shell Company	false
Entity Central Index Key	0001534969
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	Q2
Amendment Flag	false
Class A common stock
Document Information [Line Items]
Entity Common Stock, Shares Outstanding (in shares)		32,400,832
Class B common stock
Document Information [Line Items]
Entity Common Stock, Shares Outstanding (in shares)		967,759

Condensed Balance Sheets (unaud

Condensed Balance Sheets (unaudited) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Current assets:
Cash and cash equivalents	$ 4,664	$ 3,880
Marketable securities	46,276	45,199
Accounts receivable	101	160
Other receivables	0	11,310
Prepaid expenses and other current assets	502	795
Total current assets	51,543	61,344
Property and equipment, net	1,607	1,999
Long-term marketable securities	30,006	30,841
Other assets	1,705	1,257
Total assets	84,861	95,441
Current liabilities:
Accounts payable	952	1,046
Accrued and other current liabilities	3,181	2,722
Finance lease obligation, current portion	396	440
Deferred revenue	20,228	20,235
Total current liabilities	24,757	24,443
Finance lease obligation, net of current portion	23	196
Long-term portion	328	644
Total liabilities	25,108	25,283
Commitments and Contingencies
Stockholders' equity:
Common stock, $0.0001 par value; 150,000,000 Class A shares authorized; 32,386,088 and 30,736,513 Class A shares issued and outstanding as of June 30, 2024 and December 31, 2023, respectively; 1,500,000 Class B shares authorized; 1,405,259 Class B shares issued as of June 30, 2024 and December 31, 2023; 967,759 Class B shares outstanding as of June 30, 2024 and December 31, 2023.	3	3
Additional paid-in capital	323,257	317,066
Accumulated other comprehensive loss	(211)	(15)
Accumulated deficit	(263,296)	(246,896)
Total stockholders' equity	59,753	70,158
Total liabilities and stockholders' equity	$ 84,861	$ 95,441

Condensed Balance Sheets (una_2

Condensed Balance Sheets (unaudited) (Parenthetical) - $ / shares	Jun. 30, 2024	Dec. 31, 2023
Class A common stock
Common stock, par value (in shares)	$ 0.0001	$ 0.0001
Common stock, shares authorized (in shares)	150,000,000	150,000,000
Common stock, shares issued (in shares)	32,386,088	30,736,513
Common stock, shares outstanding (in shares)	32,386,088	30,736,513
Class B common stock
Common stock, par value (in shares)	$ 0.0001	$ 0.0001
Common stock, shares authorized (in shares)	1,500,000	1,500,000
Common stock, shares issued (in shares)	1,405,259	1,405,259
Common stock, shares outstanding (in shares)	967,759	967,759

Condensed Statements of Operati

Condensed Statements of Operations and Comprehensive Loss (unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Income Statement [Abstract]
Revenue	$ 24	$ 123	$ 24	$ 223
Operating expenses:
Cost of revenue	20	80	37	142
Research and development	4,406	3,688	8,089	7,791
Selling and marketing	1,099	2,872	2,326	5,690
General and administrative	3,752	4,943	7,922	9,389
Total operating expenses	9,277	11,583	18,374	23,012
Loss from operations	(9,253)	(11,460)	(18,350)	(22,789)
Interest expense	(8)	(14)	(17)	(30)
Other income, net	958	932	1,967	1,712
Net loss	$ (8,303)	$ (10,542)	$ (16,400)	$ (21,107)
Net loss per share, basic (in usd per share)	$ (0.25)	$ (0.34)	$ (0.50)	$ (0.68)
Net loss per share, diluted (in usd per share)	$ (0.25)	$ (0.34)	$ (0.50)	$ (0.68)
Weighted-average shares of common stock outstanding, basic (in shares)	32,932,903	31,077,420	32,576,470	31,048,526
Weighted-average shares of common stock outstanding, diluted (In shares)	32,932,903	31,077,420	32,576,470	31,048,526
Other comprehensive (loss) income:
Unrealized (loss) gain on available-for-sale debt securities, net of tax	$ (30)	$ (215)	$ (196)	$ 309
Total other comprehensive (loss) income	(30)	(215)	(196)	309
Comprehensive loss	$ (8,333)	$ (10,757)	$ (16,596)	$ (20,798)

Condensed Statements of Convert

Condensed Statements of Convertible Preferred Stock and Stockholders’ Equity (Deficit) (unaudited) - USD ($) $ in Thousands	Total	Common Stock (Class A and B)	Additional Paid-In Capital	Accumulated Other Comprehensive Loss	Accumulated Deficit
Balance at the beginning (in shares) at Dec. 31, 2022		31,017,946
Balance at the beginning at Dec. 31, 2022	$ 98,943	$ 3	$ 310,575	$ (981)	$ (210,654)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of stock options (in shares)		4,094
Issuance of common stock upon exercise of stock options	4		4
Stock-based compensation expense	1,304		1,304
Other comprehensive loss	524			524
Net loss	(10,565)				(10,565)
Balance at the ending (in shares) at Mar. 31, 2023		31,022,040
Balance at the ending at Mar. 31, 2023	90,210	$ 3	311,883	(457)	(221,219)
Balance at the beginning (in shares) at Dec. 31, 2022		31,017,946
Balance at the beginning at Dec. 31, 2022	98,943	$ 3	310,575	(981)	(210,654)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Other comprehensive loss	309
Net loss	(21,107)
Balance at the ending (in shares) at Jun. 30, 2023		31,198,505
Balance at the ending at Jun. 30, 2023	81,137	$ 3	313,567	(672)	(231,761)
Balance at the beginning (in shares) at Mar. 31, 2023		31,022,040
Balance at the beginning at Mar. 31, 2023	90,210	$ 3	311,883	(457)	(221,219)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of stock options (in shares)		117,839
Issuance of common stock upon exercise of stock options	178		178
Stock-based compensation expense	1,440		1,440
Other comprehensive loss	(215)			(215)
Net loss	(10,542)				(10,542)
Balance at the ending (in shares) at Jun. 30, 2023		31,198,505
Balance at the ending at Jun. 30, 2023	81,137	$ 3	313,567	(672)	(231,761)
Balance at the beginning (in shares) at Dec. 31, 2023		31,704,272
Balance at the beginning at Dec. 31, 2023	70,158	$ 3	317,066	(15)	(246,896)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of stock options (in shares)		425,749
Issuance of common stock upon exercise of stock options	1,162		1,162
Stock Issued During Period, Value, Restricted Stock Award, Gross		431,152
Stock Issued During Period, Shares, Stock Warrant Exercised		6,168
Stock-based compensation expense	1,693		1,693
Other comprehensive loss	(166)			(166)
Net loss	(8,097)				(8,097)
Balance at the ending (in shares) at Mar. 31, 2024		32,567,341
Balance at the ending at Mar. 31, 2024	64,750	$ 3	319,921	(181)	(254,993)
Balance at the beginning (in shares) at Dec. 31, 2023		31,704,272
Balance at the beginning at Dec. 31, 2023	$ 70,158	$ 3	317,066	(15)	(246,896)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of stock options (in shares)	890,054
Stock Issued During Period, Shares, Stock Warrant Exercised	7,971
Other comprehensive loss	$ (196)
Net loss	(16,400)
Balance at the ending (in shares) at Jun. 30, 2024		33,353,847
Balance at the ending at Jun. 30, 2024	59,753	$ 3	323,257	(211)	(263,296)
Balance at the beginning (in shares) at Mar. 31, 2024		32,567,341
Balance at the beginning at Mar. 31, 2024	64,750	$ 3	319,921	(181)	(254,993)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of stock options (in shares)		464,305
Issuance of common stock upon exercise of stock options	1,258		1,258
Stock Issued During Period, Value, Restricted Stock Award, Gross		287,729
Stock Issued During Period, Shares, Stock Warrant Exercised		1,803
Stock-based compensation expense	2,023		2,023
Other comprehensive loss	(30)			(30)
Net loss	(8,303)				(8,303)
Balance at the ending (in shares) at Jun. 30, 2024		33,353,847
Balance at the ending at Jun. 30, 2024	$ 59,753	$ 3	$ 323,257	$ (211)	$ (263,296)

Condensed Statements of Conve_2

Condensed Statements of Convertible Preferred Stock and Stockholders’ Equity (Deficit) (unaudited) (Parenthetical) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2024	Mar. 31, 2024	Jun. 30, 2023	Mar. 31, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023	Dec. 31, 2022
Issuance of common stock upon exercise of stock options (in shares)					890,054
Issuance of common stock upon exercise of stock options	$ 1,258	$ 1,162	$ 178	$ 4
Stock-based compensation expense	2,023	1,693	1,440	1,304
Other comprehensive loss	(30)	(166)	(215)	524	$ (196)	$ 309
Net loss	(8,303)	(8,097)	(10,542)	(10,565)	(16,400)	(21,107)
Stockholders' Equity Attributable to Parent	59,753	$ 64,750	81,137	$ 90,210	$ 59,753	$ 81,137	$ 70,158	$ 98,943
Stock Issued During Period, Value, Employee Stock Purchase Plan	$ 55		$ 66
Common Stock (Class A and B)
Issuance of common stock upon exercise of stock options (in shares)	464,305	425,749	117,839	4,094
Common stock, shares issued (in shares)	33,353,847	32,567,341	31,198,505	31,022,040	33,353,847	31,198,505	31,704,272	31,017,946
Stockholders' Equity Attributable to Parent	$ 3	$ 3	$ 3	$ 3	$ 3	$ 3	$ 3	$ 3
Stock Issued During Period, Shares, Employee Stock Purchase Plans	32,669		58,626
Additional Paid-In Capital
Issuance of common stock upon exercise of stock options	$ 1,258	1,162	$ 178	4
Stock-based compensation expense	2,023	1,693	1,440	1,304
Stockholders' Equity Attributable to Parent	323,257	319,921	313,567	311,883	323,257	313,567	317,066	310,575
Stock Issued During Period, Value, Employee Stock Purchase Plan	55		66
Accumulated Other Comprehensive Loss
Other comprehensive loss	(30)	(166)	(215)	524
Stockholders' Equity Attributable to Parent	(211)	(181)	(672)	(457)	(211)	(672)	(15)	(981)
Accumulated Deficit
Net loss	(8,303)	(8,097)	(10,542)	(10,565)
Stockholders' Equity Attributable to Parent	$ (263,296)	$ (254,993)	$ (231,761)	$ (221,219)	$ (263,296)	$ (231,761)	$ (246,896)	$ (210,654)

Condensed Statements of Cash Fl

Condensed Statements of Cash Flows (unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023
Cash flows from operating activities
Net loss	$ (16,400)	$ (21,107)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	421	472
Operating Lease, Right-of-Use Asset, Amortization Expense	278	259
Noncash Investment Income Expense Net	(632)	(426)
Stock-based compensation	3,716	2,744
Other	16	12
Changes in operating assets and liabilities:
Accounts receivable	59	(50)
Other receivables	11,310	6,000
Prepaid expenses and other assets	203	872
Accounts payable	(42)	(289)
Accrued and other current liabilities	144	(1,284)
Deferred revenue	(7)	(32)
Net cash used in operating activities	(934)	(12,829)
Cash flows from investing activities
Purchases of marketable securities	(26,556)	(23,068)
Proceeds from maturities and sales of marketable securities	26,735	38,113
Purchases of property and equipment	(22)	(86)
Payments to Acquire Intangible Assets	(697)	0
Net cash (used in) provided by investing activities	(540)	15,228
Cash flows from financing activities
Proceeds from exercise of stock options	2,420	182
Finance lease principal payments	(217)	(240)
Net cash provided by financing activities	2,258	8
Net increase in cash and cash equivalents	784	2,407
Cash and cash equivalents at beginning of period	3,880	29,878
Cash and cash equivalents at end of period	4,664	32,285
Supplemental disclosure of cash flow information
Cash paid for interest	17	30
Supplemental disclosure of non-cash investing and financing information
Purchases of property and equipment in accounts payable and accrued and other current liabilities	8	0
Proceeds from disposal of property and equipment	0	269
Proceeds from employee stock purchase plan	$ 55	$ 66

Description of Business and Fin

Description of Business and Financial Condition	6 Months Ended
	Jun. 30, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of Business and Financial Condition	Description of Business and Financial Condition Sera Prognostics, Inc. (the “Company”) is a women’s health company utilizing its proprietary proteomics and bioinformatics platform, and significant data resources, to improve maternal and neonatal health by discovering, developing, and commercializing blood-based biomarker tests and predictive analytic products and services. The Company was incorporated in the State of Delaware on January 17, 2008 and its operations are located in Salt Lake City, Utah, including a Clinical Laboratory Improvement Amendments (“CLIA”)-certified laboratory. Since its inception, the Company’s activities have consisted of performing research and development and conducting clinical studies for its pipeline products and services, acquiring product rights, raising capital, establishing facilities, and organizing commercial operations to market its testing and analytics products, primarily the PreTRM test. Liquidity and Capital Resources The accompanying condensed financial statements have been prepared on a going concern basis, which contemplates the realization of assets and the satisfaction of liabilities and commitments in the normal course of business. The Company has incurred net losses and negative cash flows from operations since inception and had an accumulated deficit of $263.3 million as of June 30, 2024. The Company’s management expects the Company to incur significant additional operating losses and negative cash flows for the foreseeable future, principally as a result of the Company’s activities relating to the PreTRM test and the Company’s other pipeline products and services, including clinical and preclinical trials and anticipated research and development activities as well as commercialization activities. There can be no assurance that the Company will eventually achieve significant revenues or profitability to sustain operations, or if achieved, can sustain either on a continuing basis. If the Company is unable to achieve significant revenues or raise additional funds, when needed, it may not be able to continue the development or commercialization of its products and services and could be required to delay, scale back, or abandon some or all of its operations. No assurance can be given that the Company will be successful in raising the required capital on reasonable terms and at the required times, or at all. Any additional equity financing, if available to the Company, may not be available on favorable terms and may be dilutive to current stockholders, and any debt financing, if available, may involve restrictive covenants and dilutive financing instruments. The Company’s future operations are highly dependent on a combination of factors, including (i) the commercialization and market acceptance of the PreTRM test and the successful development, commercial launch, marketing, and distribution of other pipeline products and services; (ii) the success of scientific and clinical studies and other research and development programs that support current and future products and services; (iii) the development of competitive products by other biotechnology and laboratory companies; (iv) the Company’s ability to manage growth of the organization; (v) the Company’s ability to protect its intellectual property, technology, products and services; and, ultimately (vi) the timely and successful completion of any additional financing. The principal sources of the Company’s working capital to date have been the proceeds from the sale and issuance of convertible preferred stock and convertible notes, bank loans, and the sale and issuance of Class A common stock in an initial public offering (“IPO”), which was completed in July 2021. As of June 30, 2024, the Company had aggregate cash, cash equivalents, and available-for-sale securities of $80.9 million. See Note 3—Cash, Cash Equivalents and Marketable Securities. The Company believes that its existing financial resources are sufficient to continue operating activities at least 12 months from the issuance date of these unaudited condensed financial statements.

Significant Accounting Policies

Significant Accounting Policies	6 Months Ended
	Jun. 30, 2024
Accounting Policies [Abstract]
Significant Accounting Policies	Significant Accounting Policies Basis of Presentation The accompanying unaudited condensed financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”) and applicable rules and regulations of the U.S. Securities and Exchange Commission (the “SEC”) regarding interim financial reporting. Certain information and note disclosures normally included in the financial statements prepared in accordance with U.S. GAAP have been condensed or omitted pursuant to such rules and regulations. As such, these unaudited condensed financial statements should be read in conjunction with the audited financial statements and accompanying notes included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2023. The unaudited interim condensed financial statements have been prepared on a basis consistent with the audited annual financial statements as of and for the year ended December 31, 2023, and, in the opinion of the Company’s management, reflect all adjustments, consisting solely of normal recurring adjustments, necessary for the fair presentation of the Company’s financial results. The balance sheet as of December 31, 2023 has been derived from the audited financial statements at that date but does not include all information and footnotes required by U.S. GAAP for complete financial statements. The results of the three and six months ended June 30, 2024 are not necessarily indicative of the results to be expected for the full year ending December 31, 2024, or any other period. There have been no significant changes in the Company’s significant accounting policies during the six months ended June 30, 2024, as compared with those disclosed in its Annual Report on Form 10-K for the year ended December 31, 2023 filed with the SEC on March 20, 2024. Any reference in these notes to applicable accounting guidance is meant to refer to the authoritative U.S. GAAP included in the Accounting Standards Codification (“ASC”), and Accounting Standards Updates (“ASU”) issued by the Financial Accounting Standards Board (“FASB”). Use of Estimates The preparation of the condensed financial statements in conformity with U.S. GAAP requires the Company’s management to make estimates and assumptions that affect the amounts reported in the condensed financial statements and accompanying notes. The Company evaluates these estimates on an ongoing basis. The Company bases these estimates on historical and anticipated results, trends, and various other assumptions that the Company believes are reasonable under the circumstances, including assumptions as to future events. Actual results could differ materially from those estimates. The Company’s financial statements as of and for the three and six months ended June 30, 2024 reflect the Company’s estimates of the impact of the current macroeconomic environment, including the impact of inflation and higher interest rates. The extent to which these conditions will directly or indirectly impact the Company’s business, results of operations, and financial condition is uncertain. The Company is not aware of any specific event or circumstance that would require an update to its estimates, judgments and assumptions or a revision of the carrying value of the Company’s assets or liabilities as of the date of this filing. Recently Issued Accounting Pronouncements Not Yet Adopted In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures , which is intended to improve the transparency of income tax disclosures by requiring consistent categories and greater disaggregation of information in the effective tax rate reconciliation and income taxes paid by jurisdiction. The ASU is effective for public business entities’ annual periods beginning after December 15, 2024, with early adoption permitted. The Company is currently evaluating the impact of adopting this guidance on its financial statements. In November 2023, the FASB issued ASU No. 2023-07, Improvements to Reportable Segments Disclosures. While ASU 2023-07 requires incremental disclosures, it does not change how an entity identifies its operating segments, aggregates those operating segments, or applies the quantitative thresholds to determine reportable segments. This ASU is effective for all public business entities for fiscal years beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024. Entities must adopt the changes to the segment reporting guidance on a retrospective basis. The Company is currently evaluating the impact of adopting this guidance on its financial statements. Early adoption is permitted; however, the Company is not early adopting the standard.

Cash, Cash Equivalents and Mark

Cash, Cash Equivalents and Marketable Securities	6 Months Ended
	Jun. 30, 2024
Cash and Cash Equivalents [Abstract]
Cash, Cash Equivalents and Marketable Securities	Cash, Cash Equivalents and Marketable Securities The Company has classified its marketable securities as available-for-sale. The Company’s cash, cash equivalents and marketable securities by major security type as of June 30, 2024 and December 31, 2023 were as follows (in thousands): June 30, 2024 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value Cash and cash equivalents: Cash $ 1,761 $ — $ — $ 1,761 Money market funds 2,903 — — 2,903 Total cash and cash equivalents 4,664 — — 4,664 Current marketable securities: Commercial paper 7,939 — (9) 7,930 Corporate debt securities 11,823 — (23) 11,800 U.S. federal agency securities 20,331 — (78) 20,253 U.S. government securities 6,321 — (28) 6,293 Total current marketable securities 46,414 — (138) 46,276 Long-term marketable securities: Corporate debt securities 26,998 21 (92) 26,927 Municipal debt securities 3,081 — (2) 3,079 Total long-term marketable securities 30,079 21 (94) 30,006 Total cash, cash equivalents and marketable securities $ 81,157 $ 21 $ (232) $ 80,946 December 31, 2023 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value Cash and cash equivalents: Cash $ 2,608 $ — $ — $ 2,608 Money market funds 1,272 — — 1,272 Total cash and cash equivalents 3,880 — — 3,880 Current marketable securities: Commercial paper 11,769 6 (2) 11,773 Corporate debt securities 1,155 — (2) 1,153 U.S. federal agency securities 19,644 — (102) 19,542 U.S. government securities 12,812 — (81) 12,731 Total current marketable securities 45,380 6 (187) 45,199 Long-term marketable securities: U.S. federal agency securities 9,406 27 (17) 9,416 U.S. government securities 4,388 3 (5) 4,386 Corporate debt securities 16,880 159 — 17,039 Total long-term marketable securities 30,674 189 (22) 30,841 Total cash, cash equivalents and marketable securities $ 79,934 $ 195 $ (209) $ 79,920 The following tables summarize the Company’s available-for-sale debt securities and cash equivalents with unrealized losses as of June 30, 2024 and December 31, 2023, aggregated by major security type and the length of time that individual securities have been in a continuous loss position (in thousands): June 30, 2024 Less than 12 months 12 months or greater Total Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses Commercial paper $ 7,930 $ (9) $ — $ — $ 7,930 $ (9) Corporate debt securities 29,129 (111) 1,151 (4) 30,280 (115) U.S. federal agency securities 4,790 (14) 14,357 (64) 19,147 (78) U.S. government securities 1,475 (3) 4,818 (25) 6,293 (28) Municipal debt securities $ 3,079 $ (2) $ — $ — 3,079 (2) Total $ 46,403 $ (139) $ 20,326 $ (93) $ 66,729 $ (232) December 31, 2023 Less than 12 months 12 months or greater Total Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses Commercial paper $ 5,453 $ (2) $ — $ — $ 5,453 $ (2) Corporate debt securities 1,153 (2) — — 1,153 (2) U.S. federal agency securities 15,308 (52) 8,751 (67) 24,059 (119) U.S. government securities 4,769 (13) 10,895 (73) 15,664 (86) Total $ 26,683 $ (69) $ 19,646 $ (140) $ 46,329 $ (209) As of June 30, 2024 and December 31, 2023, the Company had not recorded any allowance for credit losses related to its available-for-sale securities. The Company attributes the declines in the fair value of its available-for-sale securities to normal market and interest rate fluctuations. The declines in fair value are not attributed to declines in credit quality. The Company does not intend to sell investments while they are in an unrealized loss position and does not believe that it is more likely than not that the Company will be required to sell the investments before recovery of their amortized cost basis, which may be maturity. All of the Company’s investments mature in less than three years. The Company’s marketable securities classified by contractual maturities as of June 30, 2024 were as follows (in thousands): Amortized Cost Fair Value Due within one year $ 46,414 $ 46,276 Due after one year through five years 30,079 30,006 Total $ 76,493 $ 76,282

Property and Equipment

Property and Equipment	6 Months Ended
	Jun. 30, 2024
Property, Plant and Equipment [Abstract]
Property and Equipment	Property and Equipment The following table presents the components of property and equipment, net, as of June 30, 2024 and December 31, 2023 (in thousands): June 30, December 31, Laboratory equipment $ 5,742 $ 5,734 Computer equipment 1,074 1,054 Leasehold improvements 772 772 Software 1,141 1,141 Furniture and fixtures 320 320 Total property and equipment 9,049 9,021 Less accumulated depreciation and amortization (7,442) (7,022) Property and equipment, net $ 1,607 $ 1,999 Depreciation and amortization expense was $0.2 million for each of the three months ended June 30, 2024 and 2023. Depreciation and amortization expense was $0.4 million and $0.5 million for the six months ended June 30, 2024 and 2023, respectively.

Other Assets

Other Assets	6 Months Ended
	Jun. 30, 2024
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Other Assets Disclosure	5. Other Assets The following table presents the components of other assets as of June 30, 2024 and December 31, 2023 (in thousands): June 30, December 31, Operating right-of-use asset $ 902 $ 1,180 Intangible assets 697 — Other assets 106 77 Total other assets $ 1,705 $ 1,257 During the six months ended June 30, 2024, the Company acquired domain names resulting in capitalized intangible assets of $697,000. The Company determined that the domain names have an indefinite useful life and are therefore not subject to amortization. The Company assesses its intangible assets for impairment annually, or more frequently if circumstances dictate.

Accrued and Other Current Liabi

Accrued and Other Current Liabilities	6 Months Ended
	Jun. 30, 2024
Accounts Payable and Accrued Liabilities, Current [Abstract]
Accrued and Other Current Liabilities	Accrued and Other Current Liabilities The following table presents the components of accrued and other current liabilities as of June 30, 2024 and December 31, 2023 (in thousands): June 30, December 31, Accrued compensation $ 513 $ 779 Accrued vacation 466 365 Accrued 401(k) matching contributions 216 74 Operating lease liability, current portion 610 578 Other current liabilities 1,376 926 Total accrued and other current liabilities $ 3,181 $ 2,722

Other Income, net

Other Income, net	6 Months Ended
	Jun. 30, 2024
Other Income and Expenses [Abstract]
Other Income, net	Other Income, net The following table presents the components of other income, net, for the three and six months ended June 30, 2024 and 2023 (in thousands): Three Months Ended Six Months Ended 2024 2023 2024 2023 Interest income $ 671 $ 337 $ 1,341 $ 593 Investment income, net 287 595 626 1,119 Other income, net $ 958 $ 932 $ 1,967 $ 1,712

Fair Value Measurements

Fair Value Measurements	6 Months Ended
	Jun. 30, 2024
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements As of June 30, 2024 and December 31, 2023, the carrying amounts of the Company’s receivables, prepaid and other current assets, accounts payable, and accrued and other current liabilities approximate their fair values, principally due to the short-term nature of the assets and liabilities. The recorded values of the finance leases approximate fair value as the interest rates approximate market interest rates. Money market funds are highly liquid investments and are actively traded. The pricing information on money market funds is readily available and can be independently validated as of the measurement date. This approach results in the classification of these securities as Level 1 of the fair value hierarchy. U.S. government agency bonds, U.S. government bonds, commercial paper, corporate debt securities, and municipal debt securities are measured at fair value using Level 2 inputs. The Company reviews trading activity and pricing for these investments as of each measurement date. The Company follows a fair value hierarchy that prioritizes the inputs to valuation techniques used to measure fair value. Fair value is defined as an exit price, representing the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. As such, fair value is a market-based measurement that should be determined based on assumptions that market participants would use in pricing an asset or liability. The three levels of the fair value hierarchy are as follows: Level 1 inputs are observable, quoted prices (unadjusted) in active markets for identical assets or liabilities that the Company can access at the measurement date. Level 2 inputs are observable inputs other than quoted prices included in Level 1 that are observable either directly or indirectly or quoted prices in markets that are not active; or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities. Level 3 inputs are unobservable inputs in which there is little or no market data, which require the Company to develop its own assumptions. The following table shows the Company’s assets measured at fair value on a recurring basis by level within the fair value hierarchy (in thousands) as of June 30, 2024: Level 1 Level 2 Level 3 Assets: Cash equivalents: Money market funds $ 2,903 $ — $ — Marketable securities: Commercial paper — 7,930 — Corporate debt securities — 38,727 — Municipal debt securities — 3,079 — U.S. federal agency securities — 20,253 — U.S. government securities — 6,293 — Total assets $ 2,903 $ 76,282 $ — The following table shows the Company’s assets measured at fair value on a recurring basis by level within the fair value hierarchy (in thousands) as of December 31, 2023: Level 1 Level 2 Level 3 Assets: Cash equivalents: Money market funds $ 1,272 $ — $ — Marketable securities: Commercial paper — 11,773 — Corporate debt securities — 18,192 — U.S. federal agency securities — 28,958 — U.S. government securities — 17,117 — Total assets $ 1,272 $ 76,040 $ —

Related Party Transactions

Related Party Transactions	6 Months Ended
	Jun. 30, 2024
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions In June 2019, the Company entered into a master services agreement with Carelon Research, a subsidiary of Elevance Health, Inc. (“Elevance Health”). This agreement covers a range of research projects, including Carelon Research’s role as a contract research organization for the P rematurity R isk Assessment Combined With Clinical I nterventions for Improving Neonatal outco ME s (“PRIME”) study. The Company paid fees related to this agreement of $0.8 million for each of the three months ended June 30, 2024 and 2023, and $1.4 million and $1.7 million for the six months ended June 30, 2024 and 2023, respectively, which were recorded in research and development expenses in the Company’s condensed statements of operations and comprehensive loss. In November 2020, the Company entered into a Laboratory Services Agreement with Elevance Health related to the PRIME study. This agreement provides a contracted rate for certain tests performed pursuant to the study. In December 2023, enrollment in the PRIME study was stopped due to efficacy, and as such, there was an immaterial amount of revenue recognized related to this agreement for the three and six months ended June 30, 2024. The Company recognized revenue related to this agreement of $14 thousand and $34 thousand for the three and six months ended June 30, 2023. In February 2021, the Company entered into a commercial collaboration agreement with Elevance Health and its affiliates (the “Commercial Collaboration Agreement”). The Commercial Collaboration Agreement provides defined payment within a defined period for use of the PreTRM test within Elevance Health’s network of covered members. Pursuant to the Commercial Collaboration Agreement, Elevance Health agreed to purchase a certain minimum number of tests for each of the first three years of the term of the agreement. Additionally, Elevance Health agreed to pay a certain minimum amount per year for the first three years of the term of the Commercial Collaboration Agreement. The Company received $11.2 million during the six months ended June 30, 2024, which amount related to the minimum payments for the year ended December 31, 2023. Such minimum payments were initially recorded as deferred revenue. Deferred revenue is recognized as revenue when the Company delivers PreTRM test results to Elevance Health patients pursuant to the Commercial Collaboration Agreement. The Company also agreed to develop a sales, marketing, and customer service program, and to provide training and marketing to duly licensed physicians specializing in obstetrics and gynecology or family medicine, or licensed nurse midwives, at the reasonable request of Elevance Health. Elevance Health has been participating in the Company’s PRIME study, and at the conclusion of the PRIME study, under the Commercial Collaboration Agreement, the parties agreed to use commercially reasonable efforts to enter into Elevance Health’s standard lab provider agreement. Unless earlier terminated due to breach, the Commercial Collaboration Agreement will remain in effect until the later of (a) the third anniversary of the effective date or (b) the date on which Elevance Health has purchased a fixed number of PreTRM tests as agreed by the parties. The Commercial Collaboration Agreement with Elevance Health is considered to be within the scope of ASC Topic 808, Collaborative Arrangements (“ASC 808”), as the parties are active participants and exposed to the risks and rewards of the collaborative activity. The Company determined the PreTRM tests to be a performance obligation for which Elevance Health is a customer and a unit of account within the scope of ASC 606. The associated transaction price is based on the contractual minimum number of tests and the agreed upon defined payment amount per test. The transaction price was allocated to this single performance obligation, which will be recognized upon delivery of test results expected to occur over the term of the agreement. All other items promised to Elevance Health are immaterial in the context of the Commercial Collaboration Agreement. There were no material revenues related to the Commercial Collaboration Agreement for the three and six months ended June 30, 2024 and 2023.

Capital Structure

Capital Structure	6 Months Ended
	Jun. 30, 2024
Stockholders' Equity Note [Abstract]
Capital Structure	Capital Structure The Company has two authorized classes of common stock, Class A and Class B. The rights of the holders of Class A and Class B common stock are identical, except with respect to voting and conversion. Each share of Class A common stock is entitled to one vote and shares of Class B common stock are non-voting. Each share of Class B common stock may be converted at any time to one share of Class A common stock at the option of its holder, subject to the ownership limitations provided for in the Company’s amended and restated certificate of incorporation. The following shares of Class A common stock were reserved for future issuance: June 30, December 31, Warrants to purchase Class A common stock 2,649,720 2,775,978 Options to purchase Class A common stock 6,336,742 7,251,663 Restricted stock units outstanding 2,118,834 2,692,459 Class A common stock available for future grants under the 2021 Equity Incentive Plan 2,111,162 1,002,091 Class A common stock available for future grants under the 2021 Employee Stock Purchase Plan 1,076,364 801,668 Total 14,292,822 14,523,859

Stock-Based Compensation

Stock-Based Compensation	6 Months Ended
	Jun. 30, 2024
Share-Based Payment Arrangement [Abstract]
Stock-Based Compensation	Stock-Based Compensation Equity Incentive Plans In November 2011, the Company established the 2011 Employee, Director and Consultant Equity Incentive Plan (the “2011 Plan”) and reserved shares of the Company’s common stock for sale and issuance under the 2011 Plan. Options granted under the 2011 Plan generally vest over a four-year period and generally expire ten years from the date of grant. Options are exercisable only to the extent vested. The 2011 Plan terminated in November 2021, and accordingly, no additional shares are available for grant under the 2011 Plan. The 2011 Plan continues to govern outstanding awards granted under the 2011 Plan. The 2021 Equity Incentive Plan (the “2021 Plan”) was established in July 2021. The 2021 Plan provides for the grant of incentive and non-statutory stock options as well as other stock rights to employees, directors, and consultants of the Company. Options generally vest over a four-year period, are exercisable only to the extent vested, and generally expire ten years from the date of grant. Restricted stock units (“RSUs”) generally vest over either a two-year or four-year period. The 2021 Plan includes provisions for annual automatic increases to the number of shares of Class A common stock reserved for issuance under the 2021 Plan. In addition, any shares that otherwise would be returned to the 2011 Plan as a result of the expiration or cancellation of stock options may be added to the 2021 Plan. As of June 30, 2024, there were 2,111,162 shares of the Company’s Class A common stock that were available for future grants under the 2021 Plan. The 2021 Employee Stock Purchase Plan (the “2021 ESPP”) was established in July 2021. The 2021 ESPP includes provisions for annual automatic increases to the number of shares of Class A common stock reserved for issuance under the 2021 ESPP. As of June 30, 2024, there were 1,076,364 shares of the Company’s Class A common stock that were available for future grants under the 2021 ESPP. Stock Options Unless otherwise noted, references to “options” in the subsequent disclosures, refers to the combined incentive and non-statutory stock options issued as employee and non-employee stock-based compensation, and authorized under the 2011 Plan and the 2021 Plan. The following table summarizes information about these options granted and outstanding: Number of Weighted- Weighted- Aggregate Outstanding — December 31, 2023 7,251,663 $ 3.66 6.9 $ 20,014 Granted 73,843 8.43 Expired — — Cancelled (98,710) 3.62 Exercised (890,054) 2.72 Outstanding — June 30, 2024 6,336,742 $ 3.84 6.7 $ 16,497 Vested and expected to vest at June 30, 2024 6,257,911 $ 3.83 6.7 $ 16,355 Vested and exercisable at June 30, 2024 5,174,134 $ 3.54 6.5 $ 14,747 RSUs The following table summarizes information about RSUs granted and outstanding under the 2021 Plan: Number of Awards Weighted-Average Grant Date Fair Value Outstanding — December 31, 2023 2,692,459 $ 2.01 Granted 188,173 9.00 Forfeited (42,917) 2.05 Vested (718,881) 2.53 Outstanding — June 30, 2024 2,118,834 $ 2.46 Stock-Based Compensation Expense The following table presents the impact of stock-based compensation expense in the statements of operations for the periods indicated (in thousands): Three Months Ended Six Months Ended 2024 2023 2024 2023 Research and development expense $ 918 $ 382 $ 1,444 $ 732 Sales and marketing expense 92 294 177 477 General and administrative expense 1,013 764 2,095 1,535 Total employee stock-based compensation $ 2,023 $ 1,440 $ 3,716 $ 2,744 The information about unrecognized stock-based compensation expense for outstanding unvested stock options and RSUs as of June 30, 2024 was as follows (in thousands, except years): Unrecognized Stock-Based Compensation Expense Weighted-Average Period of Recognition (in years) Stock Options $ 3,550 1.3 RSUs 3,969 2.0 Total unrecognized stock-based compensation expense $ 7,519

Warrants

Warrants	6 Months Ended
	Jun. 30, 2024
Warrants and Rights Note Disclosure [Abstract]
Warrants	Warrants All outstanding common stock warrants were exercisable immediately when granted. All outstanding common stock warrants are exercisable for shares of Class A common stock. The Company’s common stock warrants outstanding were as follows: Number of Warrants Outstanding as of: Exercise Price June 30, 2024 December 31, 2023 $ 5.20 3,473 3,473 9.03 969,275 1,032,404 10.84 946,666 1,009,795 12.38 8,083 8,083 20.77 722,223 722,223 2,649,720 2,775,978

Commitments and Contingences

Commitments and Contingences	6 Months Ended
	Jun. 30, 2024
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingences	Commitments and Contingencies Leases The Company is the lessee in all of its lease arrangements. The Company did not enter into any leases with related parties during the presented periods. The Company makes assumptions and judgments when assessing contracts for lease components, determining lease classifications, and calculating right-of-use asset and lease liability values. These assumptions and judgments may include the useful lives and fair values of the leased assets, the implicit rate underlying the Company’s leases, the Company’s incremental borrowing rate or the Company’s intent to exercise or not exercise options available in lease contracts. The following table shows right-of-use assets and lease liabilities, and the associated financial statement line items as of June 30, 2024 and December 31, 2023 (in thousands): Lease-Related Assets and Liabilities Financial Statement Line Items June 30, December 31, Right-of-use assets: Operating leases Other assets $ 902 $ 1,180 Finance leases Property and equipment, net 855 1,008 Total right-of-use assets $ 1,757 $ 2,188 Lease liabilities: Operating leases Accrued and other current liabilities $ 610 $ 578 Operating lease obligation, net of current portion 328 644 Finance leases Finance lease obligation, current portion 396 440 Finance lease obligation, net of current portion 23 196 Total lease liabilities $ 1,357 $ 1,858 Lease costs and other information consisted of the following (in thousands, except terms and rates): Three Months Ended Six Months Ended 2024 2023 2024 2023 Lease cost Finance lease cost: Amortization of right-of-use assets $ 78 $ 83 $ 157 $ 166 Interest on lease liabilities 8 14 17 30 Operating lease cost 159 159 318 318 Total lease cost $ 245 $ 256 $ 492 $ 514 Other information Finance leases: Operating cash outflows $ 8 $ 14 $ 17 $ 30 Financing cash outflows $ 109 $ 120 $ 217 $ 240 Right-of-use assets obtained in exchange for lease liabilities $ — $ 18 $ — $ 18 Weighted-average remaining lease term (in years) 0.9 1.8 0.9 1.8 Weighted-average discount rate 6.6% 6.5% 6.6% 6.5% Operating leases: Operating cash outflows $ 162 $ 157 $ 323 $ 314 Right-of-use assets obtained in exchange for lease liabilities $ — $ — $ — $ — Weighted-average remaining lease term (in years) 1.5 2.5 1.5 2.5 Weighted-average discount rate 7.5% 7.5% 7.5% 7.5% Future minimum lease payments for the Company’s leases as of June 30, 2024 were as follows (in thousands): Operating Leases Finance Leases Total 2024 $ 323 $ 233 $ 556 2025 666 197 863 2026 — 2 2 2027 and thereafter — — — Total minimum lease payments 989 432 1,421 Less: imputed interest (51) (13) (64) Present value of future lease payments 938 419 1,357 Less: current portion 610 396 1,006 Long-term portion $ 328 $ 23 $ 351 Operating Leases The Company leases a total of approximately 24,300 square feet of office and laboratory space under a single non-cancelable operating lease with a termination date of December 31, 2025 (as amended, the “Office Lease”). The Office Lease includes an early termination right which termination would occur under certain circumstances, as provided in the amended Office Lease, after July 1, 2024, if exercised. The Company is not currently reasonably certain it will exercise the termination right. The implicit rate provided in the Company’s operating lease is not readily determinable. As such, the Company uses its incremental borrowing rate to calculate the present value of its operating lease liabilities. Finance Leases The Company leases certain equipment related to its information technology infrastructure and laboratory operations. All of the Company’s current finance leases include bargain purchase options that the Company is reasonably certain to exercise. The Company has elected not to separate lease and non-lease components for its equipment leases. The rates implicit in the Company’s finance leases are determinable, and the Company uses those rates to calculate the present value of its finance lease liabilities. Indemnification The Company has agreed to indemnify its officers and directors for certain events or occurrences while the officer or director is or was serving at the Company’s request in such capacity. The maximum amount of potential future indemnification is unlimited; however, the Company purchases director and officer insurance coverage that provides for corporate reimbursements of covered obligations that limits the Company’s exposure and enables it to recover a portion of potential future amounts paid. The Company is unable to reasonably estimate the maximum amount that could be payable under these arrangements since these obligations are not capped but are conditional to the unique facts and circumstances involved. Accordingly, the Company has no liabilities recorded for these agreements as of June 30, 2024 and December 31, 2023. The Company has never incurred costs to defend lawsuits or settle claims related to these indemnification agreements. Employee Agreements The Company has signed various employment agreements with key executives pursuant to which, if their employment is terminated by the Company without cause or by the employees for good reason, or following a change of control of the Company, the employees are entitled to receive certain benefits, including severance payments, accelerated vesting of stock and stock options, and certain insurance benefits. Legal Matters The Company is not currently a party to any material litigation or other material legal proceedings. The Company may, from time to time, be involved in various legal proceedings arising from the normal course of business activities, and an unfavorable resolution of any of these matters could materially affect the Company’s future results of operations, cash flows, or financial position.

Net loss per share

Net loss per share	6 Months Ended
	Jun. 30, 2024
Earnings Per Share [Abstract]
Net loss per share	Net loss per share The Company calculates net loss per share of Class A and Class B common stock using the two-class method. For periods in which the Company reports a net loss, all potentially dilutive shares are anti-dilutive and are therefore excluded from the calculation of diluted net loss per share. For the three and six months ended June 30, 2024 and 2023, the Company reported net losses and as such, basic and diluted net loss per share are the same. As the liquidation and dividend rights are identical for Class A and Class B common stock, the undistributed earnings are allocated on a proportionate basis and the resulting amount per share for Class A and Class B common stock was the same for the three and six months ended June 30, 2024 and 2023. The Company excluded the following potentially dilutive securities, presented based on amounts outstanding at each period end, from the computation of diluted net loss per share for the periods indicated because their impact would have been anti-dilutive: June 30, 2024 2023 Warrants to purchase Class A common stock 2,649,720 2,775,978 Options to purchase Class A common stock 6,336,742 8,062,442 Restricted stock units outstanding 2,118,834 240,832 Total 11,105,296 11,079,252

Pay vs Performance Disclosure

Pay vs Performance Disclosure - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2024	Mar. 31, 2024	Jun. 30, 2023	Mar. 31, 2023	Jun. 30, 2024	Jun. 30, 2023
Pay vs Performance Disclosure
Net loss	$ (8,303)	$ (8,097)	$ (10,542)	$ (10,565)	$ (16,400)	$ (21,107)

Insider Trading Arrangements

Insider Trading Arrangements	3 Months Ended
	Jun. 30, 2024 shares
Trading Arrangements, by Individual
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false
Zhenya Lindgardt [Member]
Trading Arrangements, by Individual
Name	Zhenya Lindgardt
Title	President and Chief Executive Officer
Rule 10b5-1 Arrangement Adopted	true
Adoption Date	6/15/2024
Expiration Date	7/31/2025
Aggregate Available	104,979
Austin Aerts [Member]
Trading Arrangements, by Individual
Material Terms of Trading Arrangement	The 10b5-1 trading arrangement provides for the sale of up to (i) 47,164 shares of our Class A common stock plus (ii) the net number of shares of our Class A common stock underlying certain restricted stock unit (“RSU”) awards. The number of shares to be sold pursuant to the Rule 10b5-1 trading arrangement is indeterminable with respect to the RSU awards, as such number is subject to the number of shares that will be automatically sold to satisfy applicable tax withholding obligations upon vesting of the RSU awards, which will vary based on the market price of our Class A common stock at the time of vesting.
Name	Austin Aerts
Title	Chief Financial Officer
Rule 10b5-1 Arrangement Adopted	true
Adoption Date	5/22/2024
Expiration Date	6/11/2025
John J Boniface [Member]
Trading Arrangements, by Individual
Material Terms of Trading Arrangement	The 10b5-1 trading arrangement provides for the sale of up to (i) 114,819 shares of our Class A common stock plus (ii) the net number of shares of our Class A common stock underlying certain RSU awards. The number of shares to be sold pursuant to the Rule 10b5-1 trading arrangement is indeterminable with respect to the RSU awards, as such number is subject to the number of shares that will be automatically sold to satisfy applicable tax withholding obligations upon vesting of the RSU awards, which will vary based on the market price of our Class A common stock at the time of vesting.
Name	John J. Boniface, Ph.D.
Title	Chief Scientific Officer
Rule 10b5-1 Arrangement Adopted	true
Adoption Date	5/15/2024
Expiration Date	7/31/2025
Paul Kearney [Member]
Trading Arrangements, by Individual
Material Terms of Trading Arrangement	The 10b5-1 trading arrangement provides for the sale of up to (i) 173,506 shares of our Class A common stock plus (ii) the net number of shares of our Class A common stock underlying certain RSU awards. The number of shares to be sold pursuant to the Rule 10b5-1 trading arrangement is indeterminable with respect to the RSU awards, as such number is subject to the number of shares that will be automatically sold to satisfy applicable tax withholding obligations upon vesting of the RSU awards, which will vary based on the market price of our Class A common stock at the time of vesting.
Name	Paul Kearney, Ph.D.
Title	Chief Data Officer
Rule 10b5-1 Arrangement Adopted	true
Adoption Date	5/14/2024
Expiration Date	7/31/2025
Robert G Harrison [Member]
Trading Arrangements, by Individual
Material Terms of Trading Arrangement	The 10b5-1 trading arrangement provides for the sale of up to (i) 25,670 shares of our Class A common stock plus (ii) the net number of shares of our Class A common stock underlying certain RSU awards. The number of shares to be sold pursuant to the Rule 10b5-1 trading arrangement is indeterminable with respect to the RSU awards, as such number is subject to the number of shares that will be automatically sold to satisfy applicable tax withholding obligations upon vesting of the RSU awards, which will vary based on the market price of our Class A common stock at the time of vesting.
Name	Robert G. Harrison
Title	Chief Information Officer
Rule 10b5-1 Arrangement Adopted	true
Adoption Date	5/14/2024
Expiration Date	7/31/2025
Benjamin G Jackson [Member]
Trading Arrangements, by Individual
Material Terms of Trading Arrangement	The 10b5-1 trading arrangement provides for the sale of up to (i) 96,718 shares of our Class A common stock plus (ii) the net number of shares of our Class A common stock underlying certain RSU awards and (iii) the number of shares of our Class A common stock resulting from purchases under the 2021 ESPP. The number of shares to be sold pursuant to the Rule 10b5-1 trading arrangement is indeterminable (a) with respect to the RSU awards, as such number is subject to the number of shares that will be automatically sold to satisfy applicable tax withholding obligations upon vesting of the RSU awards, which will vary based on the market price of our Class A common stock at the time of vesting and (b) with respect to the 2021 ESPP, as such number will vary based on the market price of our Class A common stock at the time of the acquisition of shares under the 2021 ESPP.
Name	Benjamin G. Jackson
Title	General Counsel
Rule 10b5-1 Arrangement Adopted	true
Adoption Date	5/20/2024
Expiration Date	7/31/2025
Gregory C Critchfield [Member]
Trading Arrangements, by Individual
Name	Gregory C. Critchfield, M.D., M.S.
Title	Director
Rule 10b5-1 Arrangement Adopted	true
Adoption Date	5/11/2024
Expiration Date	7/31/2025
Aggregate Available	175,564
Joshua Phillips [Member]
Trading Arrangements, by Individual
Name	Joshua Phillips
Title	Director
Rule 10b5-1 Arrangement Adopted	true
Adoption Date	6/14/2024
Expiration Date	4/4/2025
Aggregate Available	12,500
Jane F Barlow [Member]
Trading Arrangements, by Individual
Name	Jane F. Barlow, M.D.
Title	Director
Rule 10b5-1 Arrangement Adopted	true
Adoption Date	5/10/2024
Expiration Date	7/31/2025
Aggregate Available	102,000
Sandra AJ Lawrence [Member]
Trading Arrangements, by Individual
Name	Sandra A.J. Lawrence
Title	Director
Rule 10b5-1 Arrangement Adopted	true
Adoption Date	6/3/2024
Expiration Date	7/31/2025
Aggregate Available	13,000
Ryan Trimble [Member]
Trading Arrangements, by Individual
Material Terms of Trading Arrangement	Including transactions by trust in which Mr. Trimble has either a direct or indirect pecuniary interest.
Name	Ryan Trimble
Title	Director
Rule 10b5-1 Arrangement Adopted	true
Adoption Date	5/22/2024
Expiration Date	7/31/2025
Aggregate Available	250,229
Catalyst Health Ventures, L.P. [Member]
Trading Arrangements, by Individual
Material Terms of Trading Arrangement	Sales under the trading arrangement for CHV LP is up to 6,793 shares of our Class A common stock, sales under the trading arrangement for CHV PF is up to 9,726 shares of our Class A common stock, sales under the trading arrangement for CHV Investments is up to 17,684 shares of our Class A common stock, and sales under the trading arrangement for CHV FO is up to 8 shares of our Class A common stock.
Name	Catalyst Health Ventures, L.P.
Rule 10b5-1 Arrangement Adopted	true
Adoption Date	6/10/2024
Expiration Date	4/4/2025
Aggregate Available	34,211
Catalyst Health Ventures (PF), L.P. [Member]
Trading Arrangements, by Individual
Material Terms of Trading Arrangement	Sales under the trading arrangement for CHV LP is up to 6,793 shares of our Class A common stock, sales under the trading arrangement for CHV PF is up to 9,726 shares of our Class A common stock, sales under the trading arrangement for CHV Investments is up to 17,684 shares of our Class A common stock, and sales under the trading arrangement for CHV FO is up to 8 shares of our Class A common stock.
Name	Catalyst Health Ventures (PF), L.P.
Rule 10b5-1 Arrangement Adopted	true
Adoption Date	6/10/2024
Expiration Date	4/4/2025
Aggregate Available	34,211
CHV Investments LLC [Member]
Trading Arrangements, by Individual
Material Terms of Trading Arrangement	Sales under the trading arrangement for CHV LP is up to 6,793 shares of our Class A common stock, sales under the trading arrangement for CHV PF is up to 9,726 shares of our Class A common stock, sales under the trading arrangement for CHV Investments is up to 17,684 shares of our Class A common stock, and sales under the trading arrangement for CHV FO is up to 8 shares of our Class A common stock.
Name	CHV Investments LLC
Rule 10b5-1 Arrangement Adopted	true
Adoption Date	6/10/2024
Expiration Date	4/4/2025
Aggregate Available	34,211
Catalyst Health Ventures Follow-on Fund, L.P. [Member]
Trading Arrangements, by Individual
Material Terms of Trading Arrangement	Sales under the trading arrangement for CHV LP is up to 6,793 shares of our Class A common stock, sales under the trading arrangement for CHV PF is up to 9,726 shares of our Class A common stock, sales under the trading arrangement for CHV Investments is up to 17,684 shares of our Class A common stock, and sales under the trading arrangement for CHV FO is up to 8 shares of our Class A common stock.
Name	Catalyst Health Ventures Follow-on Fund, L.P.
Rule 10b5-1 Arrangement Adopted	true
Adoption Date	6/10/2024
Expiration Date	4/4/2025
Aggregate Available	34,211

Significant Accounting Polici_2

Significant Accounting Policies (Policies)	6 Months Ended
	Jun. 30, 2024
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying unaudited condensed financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”) and applicable rules and regulations of the U.S. Securities and Exchange Commission (the “SEC”) regarding interim financial reporting. Certain information and note disclosures normally included in the financial statements prepared in accordance with U.S. GAAP have been condensed or omitted pursuant to such rules and regulations. As such, these unaudited condensed financial statements should be read in conjunction with the audited financial statements and accompanying notes included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2023. The unaudited interim condensed financial statements have been prepared on a basis consistent with the audited annual financial statements as of and for the year ended December 31, 2023, and, in the opinion of the Company’s management, reflect all adjustments, consisting solely of normal recurring adjustments, necessary for the fair presentation of the Company’s financial results. The balance sheet as of December 31, 2023 has been derived from the audited financial statements at that date but does not include all information and footnotes required by U.S. GAAP for complete financial statements. The results of the three and six months ended June 30, 2024 are not necessarily indicative of the results to be expected for the full year ending December 31, 2024, or any other period. There have been no significant changes in the Company’s significant accounting policies during the six months ended June 30, 2024, as compared with those disclosed in its Annual Report on Form 10-K for the year ended December 31, 2023 filed with the SEC on March 20, 2024.
Use of Estimates	Use of Estimates The preparation of the condensed financial statements in conformity with U.S. GAAP requires the Company’s management to make estimates and assumptions that affect the amounts reported in the condensed financial statements and accompanying notes. The Company evaluates these estimates on an ongoing basis. The Company bases these estimates on historical and anticipated results, trends, and various other assumptions that the Company believes are reasonable under the circumstances, including assumptions as to future events. Actual results could differ materially from those estimates. The Company’s financial statements as of and for the three and six months ended June 30, 2024 reflect the Company’s estimates of the impact of the current macroeconomic environment, including the impact of inflation and higher interest rates. The extent to which these conditions will directly or indirectly impact the Company’s business, results of operations, and financial condition is uncertain. The Company is not aware of any specific event or circumstance that would require an update to its estimates, judgments and assumptions or a revision of the carrying value of the Company’s assets or liabilities as of the date of this filing.
Recently Issued Accounting Pronouncements Not Yet Adopted	Recently Issued Accounting Pronouncements Not Yet Adopted In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures , which is intended to improve the transparency of income tax disclosures by requiring consistent categories and greater disaggregation of information in the effective tax rate reconciliation and income taxes paid by jurisdiction. The ASU is effective for public business entities’ annual periods beginning after December 15, 2024, with early adoption permitted. The Company is currently evaluating the impact of adopting this guidance on its financial statements. In November 2023, the FASB issued ASU No. 2023-07, Improvements to Reportable Segments Disclosures. While ASU 2023-07 requires incremental disclosures, it does not change how an entity identifies its operating segments, aggregates those operating segments, or applies the quantitative thresholds to determine reportable segments. This ASU is effective for all public business entities for fiscal years beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024. Entities must adopt the changes to the segment reporting guidance on a retrospective basis. The Company is currently evaluating the impact of adopting this guidance on its financial statements. Early adoption is permitted; however, the Company is not early adopting the standard.

Cash, Cash Equivalents and Ma_2

Cash, Cash Equivalents and Marketable Securities (Tables)	6 Months Ended
	Jun. 30, 2024
Cash and Cash Equivalents [Abstract]
Schedule of Cash, Cash Equivalents and Marketable Securities by Major Security Type	The Company’s cash, cash equivalents and marketable securities by major security type as of June 30, 2024 and December 31, 2023 were as follows (in thousands): June 30, 2024 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value Cash and cash equivalents: Cash $ 1,761 $ — $ — $ 1,761 Money market funds 2,903 — — 2,903 Total cash and cash equivalents 4,664 — — 4,664 Current marketable securities: Commercial paper 7,939 — (9) 7,930 Corporate debt securities 11,823 — (23) 11,800 U.S. federal agency securities 20,331 — (78) 20,253 U.S. government securities 6,321 — (28) 6,293 Total current marketable securities 46,414 — (138) 46,276 Long-term marketable securities: Corporate debt securities 26,998 21 (92) 26,927 Municipal debt securities 3,081 — (2) 3,079 Total long-term marketable securities 30,079 21 (94) 30,006 Total cash, cash equivalents and marketable securities $ 81,157 $ 21 $ (232) $ 80,946 December 31, 2023 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value Cash and cash equivalents: Cash $ 2,608 $ — $ — $ 2,608 Money market funds 1,272 — — 1,272 Total cash and cash equivalents 3,880 — — 3,880 Current marketable securities: Commercial paper 11,769 6 (2) 11,773 Corporate debt securities 1,155 — (2) 1,153 U.S. federal agency securities 19,644 — (102) 19,542 U.S. government securities 12,812 — (81) 12,731 Total current marketable securities 45,380 6 (187) 45,199 Long-term marketable securities: U.S. federal agency securities 9,406 27 (17) 9,416 U.S. government securities 4,388 3 (5) 4,386 Corporate debt securities 16,880 159 — 17,039 Total long-term marketable securities 30,674 189 (22) 30,841 Total cash, cash equivalents and marketable securities $ 79,934 $ 195 $ (209) $ 79,920
Schedule of Marketable Securities Classified by Contractual Maturities	The Company’s marketable securities classified by contractual maturities as of June 30, 2024 were as follows (in thousands): Amortized Cost Fair Value Due within one year $ 46,414 $ 46,276 Due after one year through five years 30,079 30,006 Total $ 76,493 $ 76,282
Schedule of Marketable Securities and Cash Equivalents in Unrealized Loss Positions	The following tables summarize the Company’s available-for-sale debt securities and cash equivalents with unrealized losses as of June 30, 2024 and December 31, 2023, aggregated by major security type and the length of time that individual securities have been in a continuous loss position (in thousands): June 30, 2024 Less than 12 months 12 months or greater Total Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses Commercial paper $ 7,930 $ (9) $ — $ — $ 7,930 $ (9) Corporate debt securities 29,129 (111) 1,151 (4) 30,280 (115) U.S. federal agency securities 4,790 (14) 14,357 (64) 19,147 (78) U.S. government securities 1,475 (3) 4,818 (25) 6,293 (28) Municipal debt securities $ 3,079 $ (2) $ — $ — 3,079 (2) Total $ 46,403 $ (139) $ 20,326 $ (93) $ 66,729 $ (232) December 31, 2023 Less than 12 months 12 months or greater Total Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses Commercial paper $ 5,453 $ (2) $ — $ — $ 5,453 $ (2) Corporate debt securities 1,153 (2) — — 1,153 (2) U.S. federal agency securities 15,308 (52) 8,751 (67) 24,059 (119) U.S. government securities 4,769 (13) 10,895 (73) 15,664 (86) Total $ 26,683 $ (69) $ 19,646 $ (140) $ 46,329 $ (209)

Property and Equipment (Tables)

Property and Equipment (Tables)	6 Months Ended
	Jun. 30, 2024
Property, Plant and Equipment [Abstract]
Schedule of Components of Property and Equipment, Net	The following table presents the components of property and equipment, net, as of June 30, 2024 and December 31, 2023 (in thousands): June 30, December 31, Laboratory equipment $ 5,742 $ 5,734 Computer equipment 1,074 1,054 Leasehold improvements 772 772 Software 1,141 1,141 Furniture and fixtures 320 320 Total property and equipment 9,049 9,021 Less accumulated depreciation and amortization (7,442) (7,022) Property and equipment, net $ 1,607 $ 1,999

Other Assets (Tables)

Other Assets (Tables)	6 Months Ended
	Jun. 30, 2024
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Schedule of Other Assets	The following table presents the components of other assets as of June 30, 2024 and December 31, 2023 (in thousands): June 30, December 31, Operating right-of-use asset $ 902 $ 1,180 Intangible assets 697 — Other assets 106 77 Total other assets $ 1,705 $ 1,257

Accrued and Other Current Lia_2

Accrued and Other Current Liabilities (Tables)	6 Months Ended
	Jun. 30, 2024
Accounts Payable and Accrued Liabilities, Current [Abstract]
Schedule of Components of Accrued and Other Current Liabilities	The following table presents the components of accrued and other current liabilities as of June 30, 2024 and December 31, 2023 (in thousands): June 30, December 31, Accrued compensation $ 513 $ 779 Accrued vacation 466 365 Accrued 401(k) matching contributions 216 74 Operating lease liability, current portion 610 578 Other current liabilities 1,376 926 Total accrued and other current liabilities $ 3,181 $ 2,722

Other Income, net (Tables)

Other Income, net (Tables)	6 Months Ended
	Jun. 30, 2024
Other Income and Expenses [Abstract]
Schedule of Components of Other Income, Net	The following table presents the components of other income, net, for the three and six months ended June 30, 2024 and 2023 (in thousands): Three Months Ended Six Months Ended 2024 2023 2024 2023 Interest income $ 671 $ 337 $ 1,341 $ 593 Investment income, net 287 595 626 1,119 Other income, net $ 958 $ 932 $ 1,967 $ 1,712

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	6 Months Ended
	Jun. 30, 2024
Fair Value Disclosures [Abstract]
Schedule of Financial Assets that are Measured at Fair Value on a Recurring basis	The following table shows the Company’s assets measured at fair value on a recurring basis by level within the fair value hierarchy (in thousands) as of June 30, 2024: Level 1 Level 2 Level 3 Assets: Cash equivalents: Money market funds $ 2,903 $ — $ — Marketable securities: Commercial paper — 7,930 — Corporate debt securities — 38,727 — Municipal debt securities — 3,079 — U.S. federal agency securities — 20,253 — U.S. government securities — 6,293 — Total assets $ 2,903 $ 76,282 $ — The following table shows the Company’s assets measured at fair value on a recurring basis by level within the fair value hierarchy (in thousands) as of December 31, 2023: Level 1 Level 2 Level 3 Assets: Cash equivalents: Money market funds $ 1,272 $ — $ — Marketable securities: Commercial paper — 11,773 — Corporate debt securities — 18,192 — U.S. federal agency securities — 28,958 — U.S. government securities — 17,117 — Total assets $ 1,272 $ 76,040 $ —

Capital Structure (Tables)

Capital Structure (Tables)	6 Months Ended
	Jun. 30, 2024
Stockholders' Equity Note [Abstract]
Schedule of Common Stock Reserved for Future Issuance	The following shares of Class A common stock were reserved for future issuance: June 30, December 31, Warrants to purchase Class A common stock 2,649,720 2,775,978 Options to purchase Class A common stock 6,336,742 7,251,663 Restricted stock units outstanding 2,118,834 2,692,459 Class A common stock available for future grants under the 2021 Equity Incentive Plan 2,111,162 1,002,091 Class A common stock available for future grants under the 2021 Employee Stock Purchase Plan 1,076,364 801,668 Total 14,292,822 14,523,859

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	6 Months Ended
	Jun. 30, 2024
Share-Based Payment Arrangement [Abstract]
Summary of Options Granted and Outstanding	The following table summarizes information about these options granted and outstanding: Number of Weighted- Weighted- Aggregate Outstanding — December 31, 2023 7,251,663 $ 3.66 6.9 $ 20,014 Granted 73,843 8.43 Expired — — Cancelled (98,710) 3.62 Exercised (890,054) 2.72 Outstanding — June 30, 2024 6,336,742 $ 3.84 6.7 $ 16,497 Vested and expected to vest at June 30, 2024 6,257,911 $ 3.83 6.7 $ 16,355 Vested and exercisable at June 30, 2024 5,174,134 $ 3.54 6.5 $ 14,747
Share-Based Payment Arrangement, Restricted Stock and Restricted Stock Unit, Activity	The following table summarizes information about RSUs granted and outstanding under the 2021 Plan: Number of Awards Weighted-Average Grant Date Fair Value Outstanding — December 31, 2023 2,692,459 $ 2.01 Granted 188,173 9.00 Forfeited (42,917) 2.05 Vested (718,881) 2.53 Outstanding — June 30, 2024 2,118,834 $ 2.46
Schedule of Impact of Stock-based Compensation Expense in the Statements of Operations	The following table presents the impact of stock-based compensation expense in the statements of operations for the periods indicated (in thousands): Three Months Ended Six Months Ended 2024 2023 2024 2023 Research and development expense $ 918 $ 382 $ 1,444 $ 732 Sales and marketing expense 92 294 177 477 General and administrative expense 1,013 764 2,095 1,535 Total employee stock-based compensation $ 2,023 $ 1,440 $ 3,716 $ 2,744
Share-Based Payment Arrangement, Nonvested Award, Cost	The information about unrecognized stock-based compensation expense for outstanding unvested stock options and RSUs as of June 30, 2024 was as follows (in thousands, except years): Unrecognized Stock-Based Compensation Expense Weighted-Average Period of Recognition (in years) Stock Options $ 3,550 1.3 RSUs 3,969 2.0 Total unrecognized stock-based compensation expense $ 7,519

Warrants (Tables)

Warrants (Tables)	6 Months Ended
	Jun. 30, 2024
Warrants and Rights Note Disclosure [Abstract]
Schedule of Warrants or Rights	The Company’s common stock warrants outstanding were as follows: Number of Warrants Outstanding as of: Exercise Price June 30, 2024 December 31, 2023 $ 5.20 3,473 3,473 9.03 969,275 1,032,404 10.84 946,666 1,009,795 12.38 8,083 8,083 20.77 722,223 722,223 2,649,720 2,775,978

Commitment and Contingencies (T

Commitment and Contingencies (Tables)	6 Months Ended
	Jun. 30, 2024
Commitments and Contingencies Disclosure [Abstract]
Schedule of Leases in Financial Statement	The following table shows right-of-use assets and lease liabilities, and the associated financial statement line items as of June 30, 2024 and December 31, 2023 (in thousands): Lease-Related Assets and Liabilities Financial Statement Line Items June 30, December 31, Right-of-use assets: Operating leases Other assets $ 902 $ 1,180 Finance leases Property and equipment, net 855 1,008 Total right-of-use assets $ 1,757 $ 2,188 Lease liabilities: Operating leases Accrued and other current liabilities $ 610 $ 578 Operating lease obligation, net of current portion 328 644 Finance leases Finance lease obligation, current portion 396 440 Finance lease obligation, net of current portion 23 196 Total lease liabilities $ 1,357 $ 1,858
Schedule of Lease Cost and Other Information	Lease costs and other information consisted of the following (in thousands, except terms and rates): Three Months Ended Six Months Ended 2024 2023 2024 2023 Lease cost Finance lease cost: Amortization of right-of-use assets $ 78 $ 83 $ 157 $ 166 Interest on lease liabilities 8 14 17 30 Operating lease cost 159 159 318 318 Total lease cost $ 245 $ 256 $ 492 $ 514 Other information Finance leases: Operating cash outflows $ 8 $ 14 $ 17 $ 30 Financing cash outflows $ 109 $ 120 $ 217 $ 240 Right-of-use assets obtained in exchange for lease liabilities $ — $ 18 $ — $ 18 Weighted-average remaining lease term (in years) 0.9 1.8 0.9 1.8 Weighted-average discount rate 6.6% 6.5% 6.6% 6.5% Operating leases: Operating cash outflows $ 162 $ 157 $ 323 $ 314 Right-of-use assets obtained in exchange for lease liabilities $ — $ — $ — $ — Weighted-average remaining lease term (in years) 1.5 2.5 1.5 2.5 Weighted-average discount rate 7.5% 7.5% 7.5% 7.5%
Schedule of Future Minimum Lease Payments	Future minimum lease payments for the Company’s leases as of June 30, 2024 were as follows (in thousands): Operating Leases Finance Leases Total 2024 $ 323 $ 233 $ 556 2025 666 197 863 2026 — 2 2 2027 and thereafter — — — Total minimum lease payments 989 432 1,421 Less: imputed interest (51) (13) (64) Present value of future lease payments 938 419 1,357 Less: current portion 610 396 1,006 Long-term portion $ 328 $ 23 $ 351
Schedule of Future Minimum Lease Payments	Future minimum lease payments for the Company’s leases as of June 30, 2024 were as follows (in thousands): Operating Leases Finance Leases Total 2024 $ 323 $ 233 $ 556 2025 666 197 863 2026 — 2 2 2027 and thereafter — — — Total minimum lease payments 989 432 1,421 Less: imputed interest (51) (13) (64) Present value of future lease payments 938 419 1,357 Less: current portion 610 396 1,006 Long-term portion $ 328 $ 23 $ 351

Net loss per share (Tables)

Net loss per share (Tables)	6 Months Ended
	Jun. 30, 2024
Earnings Per Share [Abstract]
Schedule of Anti-dilutive Securities Excluded from the Computation of Earnings per Share	The Company excluded the following potentially dilutive securities, presented based on amounts outstanding at each period end, from the computation of diluted net loss per share for the periods indicated because their impact would have been anti-dilutive: June 30, 2024 2023 Warrants to purchase Class A common stock 2,649,720 2,775,978 Options to purchase Class A common stock 6,336,742 8,062,442 Restricted stock units outstanding 2,118,834 240,832 Total 11,105,296 11,079,252

Description of Business and F_2

Description of Business and Financial Condition (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Accumulated deficit	$ (263,296)	$ (246,896)
Fair Value	$ 80,946	$ 79,920

Cash, Cash Equivalents and Ma_3

Cash, Cash Equivalents and Marketable Securities - Cash, Cash Equivalents and Marketable Securities by Major Security Type (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 76,493
Fair Value	76,282
Amortized Cost	81,157	$ 79,934
Gross Unrealized Gains	21	195
Gross Unrealized Losses	(232)	(209)
Fair Value	80,946	79,920
Cash and cash equivalents:
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	4,664	3,880
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	4,664	3,880
Cash and cash equivalents: | Cash
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,761	2,608
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	1,761	2,608
Cash and cash equivalents: | Money market funds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,903	1,272
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	2,903	1,272
Current marketable securities:
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	46,414	45,380
Gross Unrealized Gains	0	6
Gross Unrealized Losses	(138)	(187)
Fair Value	46,276	45,199
Current marketable securities: | Commercial paper
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	7,939	11,769
Gross Unrealized Gains	0	6
Gross Unrealized Losses	(9)	(2)
Fair Value	7,930	11,773
Current marketable securities: | Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	11,823	1,155
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(23)	(2)
Fair Value	11,800	1,153
Current marketable securities: | U.S. federal agency securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	20,331	19,644
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(78)	(102)
Fair Value	20,253	19,542
Current marketable securities: | U.S. government securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	6,321	12,812
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(28)	(81)
Fair Value	6,293	12,731
Long-term marketable securities:
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	30,079	30,674
Gross Unrealized Gains	21	189
Gross Unrealized Losses	(94)	(22)
Fair Value	30,006	30,841
Long-term marketable securities: | Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	26,998	16,880
Gross Unrealized Gains	21	159
Gross Unrealized Losses	(92)	0
Fair Value	26,927	17,039
Long-term marketable securities: | U.S. federal agency securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost		9,406
Gross Unrealized Gains		27
Gross Unrealized Losses		(17)
Fair Value		9,416
Long-term marketable securities: | U.S. government securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost		4,388
Gross Unrealized Gains		3
Gross Unrealized Losses		(5)
Fair Value		$ 4,386
Long-term marketable securities: | Municipal Bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	3,081
Gross Unrealized Gains	0
Gross Unrealized Losses	(2)
Fair Value	$ 3,079

Cash, Cash Equivalents and Ma_4

Cash, Cash Equivalents and Marketable Securities - Marketable Securities and Cash Equivalents in Unrealized Loss Positions (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
Fair Value	$ 46,403	$ 26,683
Unrealized Losses	139	69
Fair Value	20,326	19,646
Unrealized Losses	93	140
Fair Value	66,729	46,329
Unrealized Losses	232	209
Commercial paper
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
Fair Value	7,930	5,453
Unrealized Losses	9	2
Fair Value	0	0
Unrealized Losses	0	0
Fair Value	7,930	5,453
Unrealized Losses	9	2
Corporate debt securities
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
Fair Value	29,129	1,153
Unrealized Losses	111	2
Fair Value	1,151	0
Unrealized Losses	4	0
Fair Value	30,280	1,153
Unrealized Losses	115	2
U.S. federal agency securities
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
Fair Value	4,790	15,308
Unrealized Losses	14	52
Fair Value	14,357	8,751
Unrealized Losses	64	67
Fair Value	19,147	24,059
Unrealized Losses	78	119
U.S. government securities
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
Fair Value	1,475	4,769
Unrealized Losses	3	13
Fair Value	4,818	10,895
Unrealized Losses	25	73
Fair Value	6,293	15,664
Unrealized Losses	28	$ 86
Municipal Bonds
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
Fair Value	3,079
Unrealized Losses	2
Fair Value	0
Unrealized Losses	0
Fair Value	3,079
Unrealized Losses	$ 2

Cash, Cash Equivalents and Ma_5

Cash, Cash Equivalents and Marketable Securities - Narrative (Details) - USD ($)	Jun. 30, 2024	Dec. 31, 2023
Cash and Cash Equivalents [Abstract]
Fair Value	$ 20,326,000	$ 19,646,000
Debt Securities, Available-for-Sale, Allowance for Credit Loss	$ 0	$ 0

Cash, Cash Equivalents and Ma_6

Cash, Cash Equivalents and Marketable Securities - Marketable Securities Classified by Contractual Maturities (Details) $ in Thousands	Jun. 30, 2024 USD ($)
Amortized Cost
Due within one year	$ 46,414
Due after one year through five years	30,079
Amortized Cost	76,493
Fair Value
Due within one year	46,276
Due after one year through five years	30,006
Fair Value	$ 76,282

Property and Equipment - Compon

Property and Equipment - Components of Property and Equipment, Net (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Property, Plant and Equipment [Line Items]
Total property and equipment	$ 9,049	$ 9,021
Less accumulated depreciation and amortization	(7,442)	(7,022)
Property and equipment, net	1,607	1,999
Laboratory equipment
Property, Plant and Equipment [Line Items]
Total property and equipment	5,742	5,734
Computer equipment
Property, Plant and Equipment [Line Items]
Total property and equipment	1,074	1,054
Leasehold improvements
Property, Plant and Equipment [Line Items]
Total property and equipment	772	772
Software
Property, Plant and Equipment [Line Items]
Total property and equipment	1,141	1,141
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Total property and equipment	$ 320	$ 320

Property and Equipment - Narrat

Property and Equipment - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Property, Plant and Equipment [Abstract]
Depreciation and amortization	$ 200	$ 200	$ 421	$ 472

Other Assets - Components of Ot

Other Assets - Components of Other Assets (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Other assets	$ 1,705	$ 1,257
Operating leases	902	1,180
Indefinite-Lived Intangible Assets (Excluding Goodwill)	697	0
Other Assets, Miscellaneous	$ 106	$ 77

Other Assets - Narrative (Detai

Other Assets - Narrative (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Indefinite-Lived Intangible Assets (Excluding Goodwill)	$ 697	$ 0

Accrued and Other Current Lia_3

Accrued and Other Current Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Accounts Payable and Accrued Liabilities, Current [Abstract]
Accrued compensation	$ 513	$ 779
Accrued vacation	466	365
Accrued 401(k) matching contributions	216	74
Operating lease liability, current portion	610	578
Other current liabilities	1,376	926
Total accrued and other current liabilities	$ 3,181	$ 2,722

Other Income, net (Details)

Other Income, net (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Other Income and Expenses [Abstract]
Interest income	$ 671	$ 337	$ 1,341	$ 593
Investment income, net	287	595	626	1,119
Other income, net	$ 958	$ 932	$ 1,967	$ 1,712

Fair Value Measurements - Finan

Fair Value Measurements - Financial Assets that are Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Assets:
Marketable securities:	$ 76,282
Level 1 | Recurring
Assets:
Total assets	2,903	$ 1,272
Level 1 | Recurring | Commercial paper
Assets:
Marketable securities:	0	0
Level 1 | Recurring | Corporate debt securities
Assets:
Marketable securities:	0	0
Level 1 | Recurring | U.S. federal agency securities
Assets:
Marketable securities:	0	0
Level 1 | Recurring | U.S. government securities
Assets:
Marketable securities:	0	0
Level 1 | Recurring | Municipal Bonds
Assets:
Marketable securities:	0
Level 1 | Recurring | Money market funds
Assets:
Cash equivalents:	2,903	1,272
Level 2 | Recurring
Assets:
Total assets	76,282	76,040
Level 2 | Recurring | Commercial paper
Assets:
Marketable securities:	7,930	11,773
Level 2 | Recurring | Corporate debt securities
Assets:
Marketable securities:	38,727	18,192
Level 2 | Recurring | U.S. federal agency securities
Assets:
Marketable securities:	20,253	28,958
Level 2 | Recurring | U.S. government securities
Assets:
Marketable securities:	6,293	17,117
Level 2 | Recurring | Municipal Bonds
Assets:
Marketable securities:	3,079
Level 2 | Recurring | Money market funds
Assets:
Cash equivalents:	0	0
Level 3 | Recurring
Assets:
Total assets	0	0
Level 3 | Recurring | Commercial paper
Assets:
Marketable securities:	0	0
Level 3 | Recurring | Corporate debt securities
Assets:
Marketable securities:	0	0
Level 3 | Recurring | U.S. federal agency securities
Assets:
Marketable securities:	0	0
Level 3 | Recurring | U.S. government securities
Assets:
Marketable securities:	0	0
Level 3 | Recurring | Municipal Bonds
Assets:
Marketable securities:	0
Level 3 | Recurring | Money market funds
Assets:
Cash equivalents:	$ 0	$ 0

Related Party Transactions (Det

Related Party Transactions (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		6 Months Ended
	Feb. 28, 2021	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Related Party Transaction [Line Items]
Operating Expenses		$ 9,277	$ 11,583	$ 18,374	$ 23,012
Revenue		24	123	24	223
Master services agreement | Healthcore Inc | Investor
Related Party Transaction [Line Items]
Operating Expenses		$ 800	800	1,400	1,700
Laboratory Services Agreement | Elevance Health, Inc | Investor
Related Party Transaction [Line Items]
Revenue			$ 14		$ 34
Commercial Collaboration Agreement | Elevance Health, Inc | Investor
Related Party Transaction [Line Items]
Term of agreement	3 years
Cash receipts				$ 11,200

Capital Structure - Narrative (

Capital Structure - Narrative (Details)	Jun. 30, 2024 common_stock_class vote
Class of Stock [Line Items]
Number of common stock classes authorized | common_stock_class	2
Common stock, conversion ratio	1
Class A common stock
Class of Stock [Line Items]
Number of votes per share | vote	1

Capital Structure - Common Stoc

Capital Structure - Common Stock (Details) - Class A common stock - shares	Jun. 30, 2024	Dec. 31, 2023
Class of Stock [Line Items]
Shares reserved for future issuance (in shares)	14,292,822	14,523,859
Restricted Stock Units (RSUs)
Class of Stock [Line Items]
Shares reserved for future issuance (in shares)	2,118,834	2,692,459
Warrants to purchase Class A common stock
Class of Stock [Line Items]
Shares reserved for future issuance (in shares)	2,649,720	2,775,978
Options to purchase Class A common stock
Class of Stock [Line Items]
Shares reserved for future issuance (in shares)	6,336,742	7,251,663
Class A common stock available for future grants under the 2021 Equity Incentive Plan
Class of Stock [Line Items]
Shares reserved for future issuance (in shares)	2,111,162	1,002,091
Class A common stock available for future grants under the 2021 Employee Stock Purchase Plan
Class of Stock [Line Items]
Shares reserved for future issuance (in shares)	1,076,364	801,668

Stock-Based Compensation - Narr

Stock-Based Compensation - Narrative (Details) - shares	1 Months Ended
	Jul. 31, 2021	Nov. 30, 2011	Jun. 30, 2024	Dec. 31, 2023
Class A common stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for future issuance (in shares)			14,292,822	14,523,859
2011 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		4 years
Expiration term		10 years
2021 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	4 years
Expiration term	10 years
2021 Plan | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	4 years
2021 Plan | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	2 years
2021 Plan | Class A common stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for future issuance (in shares)			2,111,162
2021 ESPP | Class A common stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for future issuance (in shares)			1,076,364

Stock-Based Compensation - Stoc

Stock-Based Compensation - Stock Options (Details) $ / shares in Units, $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2024 USD ($) $ / shares shares	Dec. 31, 2023 USD ($) $ / shares shares
Number of Shares Subject to Options Outstanding
Outstanding at the beginning (in shares) | shares	7,251,663
Granted (in shares) | shares	73,843
Expired (in shares) | shares	0
Cancelled (in shares) | shares	(98,710)
Exercised (in shares) | shares	(890,054)
Outstanding at the end (in shares) | shares	6,336,742	7,251,663
Number of shares subject to options outstanding, vested and expected to vest at the end (in shares) | shares	6,257,911
Number of shares subject to options outstanding, vested and exercisable at the end | shares	5,174,134
Weighted- Average Exercise Price Per Share
Outstanding at the beginning (in usd per share) | $ / shares	$ 3.66
Granted (in usd per share) | $ / shares	8.43
Expired (in usd per share) | $ / shares	0
Cancelled (in usd per share) | $ / shares	3.62
Exercised (in usd per share) | $ / shares	2.72
Outstanding at the end (in usd per share) | $ / shares	3.84	$ 3.66
Weighted average exercise price per share, vested and expected to vest at the end (in usd per share) | $ / shares	3.83
Weighted average exercise price per share, vested and exercisable at the end (in usd per share) | $ / shares	$ 3.54
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Weighted average remaining contractual life, outstanding	6 years 8 months 12 days	6 years 10 months 24 days
Weighted average remaining contractual life, vested and expected to vest at the end	6 years 8 months 12 days
Weighted average remaining contractual life, vested and exercisable at the end	6 years 6 months
Aggregate intrinsic value, outstanding | $	$ 16,497	$ 20,014
Aggregate intrinsic value, vested and expected to vest at the end | $	16,355
Aggregate intrinsic value, vested and exercisable at the end | $	$ 14,747

Stock-Based Compensation - Rest

Stock-Based Compensation - Restricted Stock Units (Details) - Restricted Stock Units (RSUs)	6 Months Ended
	Jun. 30, 2024 $ / shares shares
Number of Awards
Outstanding, beginning balance (in shares) | shares	2,692,459
Granted (in shares) | shares	188,173
Forfeited (in shares) | shares	(42,917)
Vested (in shares) | shares	(718,881)
Outstanding, ending balance (in shares) | shares	2,118,834
Weighted-Average Grant Date Fair Value
Outstanding, beginning balance (in usd per share) | $ / shares	$ 2.01
Granted (in usd per share) | $ / shares	9
Forfeited (in usd per share) | $ / shares	2.05
Vested (in usd per share) | $ / shares	2.53
Outstanding, ending balance (in usd per share) | $ / shares	$ 2.46

Stock-Based Compensation - Expe

Stock-Based Compensation - Expense (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Total employee stock-based compensation	$ 2,023	$ 1,440	$ 3,716	$ 2,744
Research and development expense
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Total employee stock-based compensation	918	382	1,444	732
Sales and marketing expense
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Total employee stock-based compensation	92	294	177	477
General and administrative expense
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Total employee stock-based compensation	$ 1,013	$ 764	$ 2,095	$ 1,535

Stock-Based Compensation - Unre

Stock-Based Compensation - Unrecognized Cost (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2024 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unamortized stock-based compensation cost	$ 3,550
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount	$ 7,519
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition	1 year 3 months 18 days
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-Based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount	$ 3,969
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition	2 years

Warrants - Common Stock Warrant

Warrants - Common Stock Warrants Outstanding (Details) - $ / shares	Jun. 30, 2024	Dec. 31, 2023
Class of Warrant or Right [Line Items]
Number of warrants outstanding (in shares)	2,649,720	2,775,978
5.20
Class of Warrant or Right [Line Items]
Exercise price (in usd per share)	$ 5.20
Number of warrants outstanding (in shares)	3,473	3,473
9.03
Class of Warrant or Right [Line Items]
Exercise price (in usd per share)	$ 9.03
Number of warrants outstanding (in shares)	969,275	1,032,404
10.84
Class of Warrant or Right [Line Items]
Exercise price (in usd per share)	$ 10.84
Number of warrants outstanding (in shares)	946,666	1,009,795
12.38
Class of Warrant or Right [Line Items]
Exercise price (in usd per share)	$ 12.38
Number of warrants outstanding (in shares)	8,083	8,083
20.77
Class of Warrant or Right [Line Items]
Exercise price (in usd per share)	$ 20.77
Number of warrants outstanding (in shares)	722,223	722,223

Warrants - Narrative (Details)

Warrants - Narrative (Details)	6 Months Ended
	Jun. 30, 2024 shares
Class of Warrant or Right [Line Items]
Class of Warrant Or Right, Exercised	(126,258)
Stock Issued During Period, Shares, Stock Warrant Exercised	7,971

Commitments and Contingences -

Commitments and Contingences - Leases in Financial Statement (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Right-of-use assets:
Operating leases	$ 902	$ 1,180
Finance leases	855	1,008
Total right-of-use assets	1,757	2,188
Lease liabilities:
Operating leases	610	578
Long-term portion	328	644
Finance lease obligation, current portion	396	440
Finance lease obligation, net of current portion	23	196
Total lease liabilities	$ 1,357	$ 1,858
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]	Other assets	Other assets
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]	Property and equipment, net	Property and equipment, net
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Accrued Liabilities and Other Liabilities	Accrued Liabilities and Other Liabilities

Commitments and Contingences _2

Commitments and Contingences - Lease Cost and Other Information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Lease cost
Amortization of right-of-use assets	$ 78	$ 83	$ 157	$ 166
Interest on lease liabilities	8	14	17	30
Operating lease cost	159	159	318	318
Total lease cost	245	256	492	514
Finance leases:
Operating cash outflows	8	14	17	30
Financing cash outflows	109	120	217	240
Right-of-use assets obtained in exchange for lease liabilities	$ 0	$ 18	$ 0	$ 18
Weighted-average remaining lease term (in years)	10 months 24 days	1 year 9 months 18 days	10 months 24 days	1 year 9 months 18 days
Weighted-average discount rate	660%	650%	660%	650%
Operating leases:
Operating cash outflows	$ 162	$ 157	$ 323	$ 314
Right-of-use assets obtained in exchange for lease liabilities	$ 0	$ 0	$ 0	$ 0
Weighted-average remaining lease term (in years)	1 year 6 months	2 years 6 months	1 year 6 months	2 years 6 months
Weighted-average discount rate	750%	750%	750%	750%

Commitments and Contingences _3

Commitments and Contingences - Future Minimum Lease Payments (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Operating Leases
2024	$ 323
2025	666
2026	0
Total minimum lease payments	989
Less: imputed interest	(51)
Present value of future lease payments	938
Less: current portion	610	$ 578
Long-term portion	328	644
Finance Leases
2024	233
2025	197
2026	2
Total minimum lease payments	432
Less: imputed interest	(13)
Present value of future lease payments	419
Less: current portion	396	440
Long-term portion	23	196
Total
2024	556
2025	863
2026	2
Total minimum lease payments	1,421
Less: imputed interest	(64)
Total lease liabilities	1,357	$ 1,858
Less: current portion	1,006
Long-term portion	351
2028	0
2028	0
2028	$ 0

Commitments and Contingences _4

Commitments and Contingences - Narrative (Details)	Jun. 30, 2024 USD ($) ft²	Dec. 31, 2023 USD ($)
Commitments And Contingencies [Line Items]
Indemnification liability | $	$ 0	$ 0
Office and laboratory space
Commitments And Contingencies [Line Items]
Number of square feet under lease | ft²	24,300

Net loss per share - Anti-Dilut

Net loss per share - Anti-Dilutive Securities Excluded from the Computation of Diluted Net Loss Per Share (Details) - shares	6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from the computation of earnings per share (in shares)	11,105,296	11,079,252
Warrants to purchase Class A common stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from the computation of earnings per share (in shares)	2,649,720	2,775,978
Options to purchase Class A common stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from the computation of earnings per share (in shares)	6,336,742	8,062,442
Restricted Stock Units (RSUs)
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from the computation of earnings per share (in shares)	2,118,834	240,832