Gyre Therapeutics (GYRE) 10-Q 7 Nov 19 2019 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2019	Oct. 25, 2019
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2019
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q3
Trading Symbol	CBIO
Entity Registrant Name	CATALYST BIOSCIENCES, INC.
Entity Central Index Key	0001124105
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Common Stock, Shares Outstanding		12,040,835
Entity Current Reporting Status	Yes
Entity Shell Company	false
Entity File Number	000-51173
Entity Tax Identification Number	56-2020050
Entity Address, Address Line One	611 Gateway Blvd.
Entity Address, Address Line Two	Suite 710
Entity Address, City or Town	South San Francisco
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	94080
City Area Code	650
Local Phone Number	871-0761
Entity Interactive Data Current	Yes
Security Exchange Name	NASDAQ
Entity Incorporation, State or Country Code	DE
Document Quarterly Report	true
Document Transition Report	false
Title of 12(b) Security	Common Stock

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 23,018	$ 31,213
Short-term investments	61,932	88,914
Restricted cash		50
Prepaid and other current assets	4,188	3,814
Total current assets	89,138	123,991
Other assets, noncurrent	257	543
Right-of-use assets	2,058
Property and equipment, net	339	386
Total assets	91,792	124,920
Current liabilities:
Accounts payable	2,123	1,248
Accrued compensation	1,576	1,495
Other accrued liabilities	4,906	2,043
Deferred rent, current portion		15
Operating lease liability	472
Total current liabilities	9,077	4,801
Operating lease liability, noncurrent	1,443
Deferred rent, noncurrent portion		174
Total liabilities	10,520	4,975
Stockholders’ equity:
Preferred stock, $0.001 par value, 5,000,000 shares authorized; zero shares issued and outstanding
Common stock, $0.001 par value, 100,000,000 shares authorized; 12,029,992 and 11,954,528 shares issued and outstanding at September 30, 2019 and December 31, 2018, respectively	12	12
Additional paid-in capital	326,139	323,279
Accumulated other comprehensive income (loss)	31	(4)
Accumulated deficit	(244,910)	(203,342)
Total stockholders’ equity	81,272	119,945
Total liabilities and stockholders’ equity	$ 91,792	$ 124,920

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Sep. 30, 2019	Dec. 31, 2018
Statement Of Financial Position [Abstract]
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares issued	12,029,992	11,954,528
Common stock, shares outstanding	12,029,992	11,954,528

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Income Statement [Abstract]
Contract revenue				$ 6
Type of Revenue [Extensible List]	cbio:ContractMember	cbio:ContractMember	cbio:ContractMember	cbio:ContractMember
Operating expenses:
Research and development	$ 9,927	$ 5,575	$ 33,066	$ 13,235
General and administrative	3,268	2,770	10,224	8,909
Total operating expenses	13,195	8,345	43,290	22,144
Loss from operations	(13,195)	(8,345)	(43,290)	(22,138)
Interest and other income, net	489	651	1,722	2,920
Net loss	$ (12,706)	$ (7,694)	$ (41,568)	$ (19,218)
Net loss per share attributable to common stockholders, basic and diluted	$ (1.06)	$ (0.64)	$ (3.47)	$ (1.75)
Shares used to compute net loss per share attributable to common stockholders, basic and diluted	12,022,620	11,942,729	11,992,240	10,967,750

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (12,706)	$ (7,694)	$ (41,568)	$ (19,218)
Other comprehensive income (loss):
Unrealized (loss) gain on available-for-sale securities	(26)	(28)	35	(24)
Total comprehensive loss	$ (12,732)	$ (7,722)	$ (41,533)	$ (19,242)

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) $ in Thousands	Total	Convertible Preferred Stock	Common Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit
Balance at Dec. 31, 2017	$ 30,774		$ 6	$ 204,262		$ (173,494)
Balance (in shares) at Dec. 31, 2017		3,680	6,081,230
Opening balance adjustment - adoption of ASC 606 at Dec. 31, 2017	207					207
Balance at Dec. 31, 2017	30,981		$ 6	204,262		(173,287)
Stock-based compensation expense	606			606
Issuance of common stock for secondary public offering, net of issuance costs	106,762		$ 4	106,758
Issuance of common stock for secondary public offering, net of issuance costs, shares			3,382,352
Issuance of common stock upon exercise of warrants	9,545		$ 2	9,543
Issuance of common stock upon exercise of warrants, shares			1,735,419
Conversion of preferred stock to common stock, shares		(3,680)	736,000
Issuance of common stock from option exercises, shares			59
Conversion of redeemable convertible notes to common stock, value	3			3
Conversion of redeemable convertible notes to common stock, shares			21
Unrealized (loss) gain on available-for-sale securities	(4)				$ (4)
Net loss	(5,042)					(5,042)
Balance at Mar. 31, 2018	142,851		$ 12	321,172	(4)	(178,329)
Balance (in shares) at Mar. 31, 2018			11,935,081
Balance at Dec. 31, 2017	30,774		$ 6	204,262		(173,494)
Balance (in shares) at Dec. 31, 2017		3,680	6,081,230
Opening balance adjustment - adoption of ASC 606 at Dec. 31, 2017	207					207
Balance at Dec. 31, 2017	30,981		$ 6	204,262		(173,287)
Unrealized (loss) gain on available-for-sale securities	(24)
Net loss	(19,218)
Balance at Sep. 30, 2018	129,951		$ 12	322,468	(24)	(192,505)
Balance (in shares) at Sep. 30, 2018			11,942,729
Balance at Mar. 31, 2018	142,851		$ 12	321,172	(4)	(178,329)
Balance (in shares) at Mar. 31, 2018			11,935,081
Stock-based compensation expense	550			550
Issuance of common stock from option exercises	36			36
Issuance of common stock from option exercises, shares			7,648
Unrealized (loss) gain on available-for-sale securities	8				8
Net loss	(6,482)					(6,482)
Balance at Jun. 30, 2018	136,963		$ 12	321,758	4	(184,811)
Balance (in shares) at Jun. 30, 2018			11,942,729
Issuance of common stock from option exercises	710			710
Unrealized (loss) gain on available-for-sale securities	(28)				(28)
Net loss	(7,694)					(7,694)
Balance at Sep. 30, 2018	129,951		$ 12	322,468	(24)	(192,505)
Balance (in shares) at Sep. 30, 2018			11,942,729
Balance at Dec. 31, 2018	119,945		$ 12	323,279	(4)	(203,342)
Balance (in shares) at Dec. 31, 2018			11,954,528
Stock-based compensation expense	829			829
Issuance of common stock from stock grants and option exercises	106			106
Issuance of common stock from stock grants and option exercises, shares			19,576
Unrealized (loss) gain on available-for-sale securities	17				17
Net loss	(15,082)					(15,082)
Balance at Mar. 31, 2019	105,815		$ 12	324,214	13	(218,424)
Balance (in shares) at Mar. 31, 2019			11,974,104
Balance at Dec. 31, 2018	$ 119,945		$ 12	323,279	(4)	(203,342)
Balance (in shares) at Dec. 31, 2018			11,954,528
Issuance of common stock from option exercises, shares	41,219
Unrealized (loss) gain on available-for-sale securities	$ 35
Net loss	(41,568)
Balance at Sep. 30, 2019	81,272		$ 12	326,139	31	(244,910)
Balance (in shares) at Sep. 30, 2019			12,029,992
Balance at Mar. 31, 2019	105,815		$ 12	324,214	13	(218,424)
Balance (in shares) at Mar. 31, 2019			11,974,104
Stock-based compensation expense	903		$ 5,999	903
Issuance of common stock from option exercises	129			129
Issuance of common stock from option exercises, shares			28,425
Unrealized (loss) gain on available-for-sale securities	44				44
Net loss	(13,780)					(13,780)
Balance at Jun. 30, 2019	93,111		$ 12	325,246	57	(232,204)
Balance (in shares) at Jun. 30, 2019			12,008,528
Stock-based compensation expense	801		$ 7,393	801
Issuance of common stock from stock grants and option exercises	92			92
Issuance of common stock from stock grants and option exercises, shares			14,071
Unrealized (loss) gain on available-for-sale securities	(26)				(26)
Net loss	(12,706)					(12,706)
Balance at Sep. 30, 2019	$ 81,272		$ 12	$ 326,139	$ 31	$ (244,910)
Balance (in shares) at Sep. 30, 2019			12,029,992

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands		9 Months Ended
		Sep. 30, 2019	Sep. 30, 2018
Operating Activities
Net loss		$ (41,568)	$ (19,218)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation expense		2,533	1,866
Depreciation and amortization		112	106
Loss on disposal of property and equipment			116
Changes in operating assets and liabilities:
Prepaid and other current assets		(477)	(2,429)
Accounts payable		875	(378)
Accrued compensation and other accrued liabilities		2,944	234
Operating lease liability and right-of-use assets		57
Deferred rent			167
Deferred revenue			(6)
Net cash flows used in operating activities		(35,524)	(19,542)
Investing Activities
Proceeds from maturities of short-term investments		133,967	60,337
Purchase of short-term investments		(106,950)	(135,612)
Purchases of property and equipment		(65)	(201)
Net cash flows provided by (used in) investing activities		26,952	(75,476)
Financing Activities
Payments for the redemption of redeemable convertible notes			(5,082)
Issuance of common stock for secondary public offering, net of issuance costs			106,762
Issuance of common stock from stock grants and option exercises		327	36
Proceeds from exercise of warrants			9,545
Net cash flow provided by financing activities		327	111,261
Net (decrease) increase in cash, cash equivalents and restricted cash		(8,245)	16,243
Cash, cash equivalents and restricted cash at beginning of the period		31,263	19,805
Cash, cash equivalents and restricted cash at end of the period	[1]	23,018	36,048
Supplemental Disclosure of Non-Cash Investing and Financing Activities:
Adoption of ASC 606			207
Conversion of redeemable convertible notes to common stock			3
Unrealized gain on investments		35	$ (24)
Right-of-use asset and operating lease liability recorded upon the adoption of ASC 842, net		$ 2,052
[1]	The following table provides a reconciliation of cash, cash equivalents and restricted cash to amounts reported within the condensed consolidated balance sheets:

Condensed Consolidated Statem_5

Condensed Consolidated Statements of Cash Flows (Unaudited) (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2019		Dec. 31, 2018	Sep. 30, 2018		Dec. 31, 2017
Statement Of Cash Flows [Abstract]
Cash and cash equivalents	$ 23,018		$ 31,213	$ 35,998
Restricted cash			50	50
Total cash and restricted cash	$ 23,018	[1]	$ 31,263	$ 36,048	[1]	$ 19,805
[1]	The following table provides a reconciliation of cash, cash equivalents and restricted cash to amounts reported within the condensed consolidated balance sheets:

Nature of Operations and Liquid

Nature of Operations and Liquidity	9 Months Ended
	Sep. 30, 2019
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Nature of Operations and Liquidity	1. Catalyst Biosciences, Inc. and its subsidiary (the “Company” or “Catalyst”) is a clinical-stage biopharmaceutical company focused on developing novel treatments for hemophilia and other rare bleeding disorders using its engineered subcutaneous (SQ) coagulation factors that promote blood clotting. The Company is located in South San Francisco, California and operates in one segment. The Company had a net loss of $41.6 million for the nine months ended September 30, 2019 and an accumulated deficit of $244.9 million as of September 30, 2019. The Company expects to continue to incur losses for the next several years. As of September 30, 2019, the Company had $85.0 million of cash, cash equivalents and short-term investments. Its primary uses of cash are to fund operating expenses, including research and development expenditures and general and administrative expenditures. Based on the current status of its research and development plans, the Company believes that its existing cash, cash equivalents and short-term investments as of September 30, 2019 will be sufficient to fund its cash requirements for at least the next 12 months from the date of the filing of this quarterly report. If, at any time, the Company’s prospects for financing its research and development programs decline, the Company may decide to reduce research and development expenses by delaying, discontinuing or reducing its funding of one or more of its research or development programs. Alternatively, the Company might raise funds through strategic collaborations, public or private financings or other arrangements. Such funding, if needed, may not be available on favorable terms, or at all.

Summary of Significant Accounti

Summary of Significant Accounting Policies	9 Months Ended
	Sep. 30, 2019
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. Basis of Presentation The Company’s condensed consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (“GAAP”) and following the requirements of the Securities and Exchange Commission (the “SEC”) for interim reporting. As permitted under those rules, certain footnotes or other financial information that are normally required by GAAP can be condensed or omitted. These financial statements have been prepared on the same basis as the Company’s annual financial statements and, in the opinion of management, reflect all adjustments, consisting only of normal recurring adjustments, which are necessary for a fair presentation of the Company’s financial information. These interim results and cash flows for any interim period are not necessarily indicative of the results to be expected for the full year. The accompanying condensed consolidated financial statements and related financial information should be read in conjunction with the consolidated financial statements filed with the Company’s Annual Report on Form 10-K for the year ended December 31, 2018 (“Annual Report”). Accounting Pronouncements Recently Adopted The Company’s significant accounting policies are included in “Part II - Item 8 - Financial Statements and Supplementary Data - Note 3 – Summary of Significant Accounting Policies” in the Company’s Annual Report. In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842), to enhance the transparency and comparability of financial reporting related to leasing arrangements. The Company adopted the standard effective January 1, 2019. There have been no other significant changes to these accounting policies during the first nine months of 2019. At the inception of an arrangement, the Company determines whether the arrangement is or contains a lease based on the unique facts and circumstances present. Operating lease liabilities and their corresponding right-of-use assets are recorded based on the present value of lease payments over the expected lease term. The interest rate implicit in lease contracts is typically not readily determinable. As such, the Company utilizes its incremental borrowing rate, which is the rate incurred to borrow on a collateralized basis over a similar term an amount equal to the lease payments in a similar economic environment. Certain adjustments to the right-of-use asset may be required for items such as initial direct costs paid or incentives received. The Company has elected to combine lease and non-lease components as a single component. The lease expense is recognized over the expected term on a straight-line basis. Operating leases are recognized on the balance sheet as right-of-use assets, operating lease liabilities, current and operating lease liabilities, non-current. As a result, the Company no longer recognizes deferred rent on the balance sheet. On January 1, 2019, the Company adopted the new lease accounting standard using the optional transition method under which comparative financial information is not restated and continues to apply the provisions of the previous lease accounting standard in its financial disclosures for the comparative periods. The Company also elected relevant optional practical expedients including that the Company did not (1) reassess whether expired or existing contracts are or contain a lease, (2) reassess the lease classifications or reassess the initial direct costs associated with expired or existing leases, and (3) separate lease and non-lease components of its operating leases in which it is the lessee. The adoption of the new lease accounting standard had an impact of approximately $2.1 million on the Company's assets and liabilities and had no impact on cash provided by or used in operating, investing or financing activities on the Company's condensed consolidated statements of cash flows. The adoption of the new lease accounting standard did not impact previously reported financial results. Investments The Company invests its excess cash in investment grade, short to intermediate-term, fixed income securities and recognizes purchased securities on the settlement date. All investments have been classified as “available-for-sale” and are carried at estimated fair value based upon quoted market prices or pricing models for similar securities. Management determines the appropriate classification of its investments at the time of purchase and reevaluates such designation as of each balance sheet date. Unrealized gains and losses are excluded from earnings and are reported as a component of comprehensive loss. Realized gains and losses and declines in fair value determined to be other-than-temporary, if any, on available-for-sale securities are included in interest and other income. The cost of securities sold is based on the specific-identification method. Interest on short-term investments is included in interest and other income.

Fair Value Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2019
Fair Value Disclosures [Abstract]
Fair Value Measurements	3. For a description of the fair value hierarchy and the Company’s fair value methodology, see “ Part II - Item 8 - Financial Statements and Supplementary Data - Note 2 – Summary of Significant Accounting Policies There were no transfers in or out of Level 1 or 2 during the periods presented. The following tables present the fair value hierarchy for assets and liabilities measured at fair value on a recurring basis as of September 30, 2019 and December 31, 2018 ( in thousands September 30, 2019 Level 1 Level 2 Level 3 Total Financial assets: Money market funds (1) $ 21,752 $ — $ — $ 21,752 U.S. government agency securities (2) 48,453 — — 48,453 Federal agency securities (2) — 13,479 — 13,479 Total financial assets $ 70,205 $ 13,479 $ — $ 83,684 (1) Included in cash and cash equivalents on the accompanying condensed consolidated balance sheets. ( 2 ) Included in short-term investments on the accompanying condensed consolidated balance sheets and are classified as available-for-sale securities. December 31, 2018 Level 1 Level 2 Level 3 Total Financial assets: Money market funds (1) $ 29,090 $ — $ — $ 29,090 Federal agency securities (1) — 999 — 999 U.S. Treasury securities (2) 74,139 74,139 Federal agency securities (2) 14,775 — 14,775 Restricted cash (money market funds) 50 — — 50 Total financial assets $ 103,279 $ 15,774 $ — $ 119,053 (1) Included in cash and cash equivalents on the accompanying condensed consolidated balance sheets. ( 2 ) Included in short-term investments on the accompanying condensed consolidated balance sheets and are classified as available-for-sale securities.

Financial Instruments

Financial Instruments	9 Months Ended
	Sep. 30, 2019
Investments All Other Investments [Abstract]
Financial Instruments	4. Cash equivalents, restricted cash and short-term investments (debt securities) which are classified as available-for-sale securities, consisted of the following ( in thousands September 30, 2019 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Money market funds (cash equivalents) $ 21,752 $ — $ — $ 21,752 U.S. government agency securities 48,439 14 — 48,453 Federal agency securities 13,462 17 — 13,479 Total financial assets $ 83,653 $ 31 $ — $ 83,684 Classified as: Cash and cash equivalents $ 21,752 Short-term investments 61,932 $ 83,684 December 31, 2018 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Money market funds (cash equivalents) $ 29,090 $ — $ — $ 29,090 Federal agency securities (cash equivalents) 999 — — 999 Restricted cash (money market funds) 50 — — 50 U.S. government agency securities 74,144 1 (6 ) 74,139 Agency securities 14,774 1 — 14,775 Total financial assets $ 119,057 $ 2 $ (6 ) $ 119,053 Classified as: Cash and cash equivalents $ 30,089 Short-term investments 88,914 Restricted cash (money market funds) 50 $ 119,053 There have been no material realized gains or losses on available-for-sale securities for the periods presented. As of September 30, 2019, the remaining contractual maturities of available-for-sale debt securities was less than one year. The carrying amounts of cash, accounts payable, and other payables approximate their fair values due to the short-term maturity of these instruments.

Lease

Lease	9 Months Ended
	Sep. 30, 2019
Lessee Disclosure [Abstract]
Lease	5. The Company leases office space for its corporate headquarters, located in South San Francisco, CA. The lease term is through April 30, 2023 and there are no stated renewal options. Operating lease liabilities are recognized based on the present value of the future minimum lease payments over the lease term. In calculating the present value of the lease payments, the Company has elected to utilize its incremental borrowing rate based on the original lease term and not the remaining lease term. The lease includes non-lease components ( e.g. For the nine months ended September 30, 2019, the Company’s operating lease expense was $0.5 million. The present value assumptions used in calculating the present value of the lease payments were as follows: Weighted-average remaining lease term 3.6 years Weighted-average discount rate 6.0 % Future lease payments under non-cancelable leases as of September 30, 2019 were as follows (in thousands) Remaining in 2019 $ 141 2020 578 2021 596 2022 613 2023 209 Total future minimum lease payments 2,137 Less imputed interest (222 ) Total lease liability $ 1,915 Supplemental cash flow information for the nine months ended September 30, 2019 related to operating leases was as follows (in thousands) Cash paid for leases that were included in operating cash outflows $ 420

Stock Based Compensation

Stock Based Compensation	9 Months Ended
	Sep. 30, 2019
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock Based Compensation	6. The following table summarizes stock option activity under the Company’s equity incentive plans and related information: Number of Shares Underlying Outstanding Options Weighted- Average Exercise Price Weighted- Average Remaining Contractual Term (Years) Outstanding — December 31, 2018 1,361,977 $ 12.04 8.71 Options granted 426,500 $ 8.00 Options exercised (41,219 ) $ 4.57 Options forfeited (166,722 ) $ 8.27 Options expired (10,698 ) $ 92.53 Outstanding — September 30, 2019 1,569,838 $ 10.99 8.38 Exercisable — September 30, 2019 649,116 $ 14.14 7.86 Vested and expected to vest — September 30, 2019 1,569,838 $ 10.99 8.38 Valuation Assumptions The Company estimated the fair value of stock options granted using the Black-Scholes option-pricing formula and a single option award approach. Due to its limited history as a public company and limited number of sales of its common stock, the Company estimated its volatility considering a number of factors including the use of the volatility of comparable public companies. The expected term of options granted under the Plan, all of which qualify as “plain vanilla” per SEC Staff Accounting Bulletin 107, is determined based on the simplified method due to the Company’s limited operating history and is 5.98 years based on the average between the vesting period and the contractual life of the option. The risk-free rate is based on the yield of a U.S. Treasury security with a term consistent with the option. This fair value is being amortized ratably over the requisite service periods of the awards, which is generally the vesting period. The fair value of employee stock options was estimated using the following weighted-average assumptions for the nine months ended September 30, 2019 and 2018: Nine Months Ended September 30, 2019 2018 Employee Stock Options: Risk-free interest rate 2.39 % 2.66 % Expected term (in years) 5.98 5.97 Dividend yield — — Volatility 89.76 % 93.60 % Weighted-average fair value of stock options granted $ 5.93 $ 10.28 Total stock-based compensation recognized was as follows ( in thousands Three Months Ended September 30, Nine Months Ended September 30, 2019 2018 2019 2018 Research and development $ 284 $ 161 $ 805 $ 418 General and administrative (1) 517 541 1,728 1,448 Total stock-based compensation $ 801 $ 702 $ 2,533 $ 1,866 (1) Included $0.03 and $0.1 million related to modifications of certain Board member stock options in the nine months ended September 30, 2019 and 2018, respectively. These modifications extended the post-termination exercise period of certain options. Also included in general and administrative stock-based compensation for the three and nine months ended September 30, 2019 is expense related to 7,393 and 13,392 shares of common stock issued to certain board members in lieu of their cash compensation, respectively. As of September 30, 2019, 1,032,672 shares of common stock were available for future grant and 1,569,838 options to purchase shares of common stock were outstanding. As of September 30, 2019, the Company had unrecognized employee stock-based compensation expense of $5.9 million, related to unvested stock awards, which is expected to be recognized over an estimated weighted-average period of 2.60 years.

Collaborations

Collaborations	9 Months Ended
	Sep. 30, 2019
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Collaborations	7 . Pfizer Pursuant to the termination agreement entered into on December 8, 2016, in connection with the termination of a prior license and development agreement, Pfizer granted the Company an exclusive license to Pfizer’s proprietary rights for manufacturing materials and processes that apply to Factor VIIa variants, CB 813a and marzeptacog alfa (activated) - MarzAA. Pfizer also transferred to the Company the IND application and documentation related to the development, manufacturing and testing of the Factor VIIa products as well as the orphan drug designation. The Company agreed to make contingent cash payments to Pfizer in an aggregate amount up to $17.5 million, payable upon the achievement of certain clinical, regulatory and commercial milestones. Following commercialization of any covered product, Pfizer will also receive a single-digit royalty on net product sales on a country-by-country basis for a predefined royalty term. In February 2018, the Company paid Pfizer a $1 million milestone payment based on the dosing of the first patient in its Phase 2 study; the amount was recorded as a research and development expense. No payments were made to Pfizer in the first nine months of 2019. ISU Abxis In December 2018, the Company entered into an amended and restated license agreement with ISU Abxis (the “A&R ISU Abxis Agreement”), which amended and restated its previous license and collaboration agreement with ISU Abxis previously entered into in September 2013, as subsequently amended in October 2014 and December 2016 (the “Original ISU Abxis Agreement”) ISU Abxis will receive commercialization rights in South Korea to the Company’s engineered Factor IX dalcinonacog alfa - DalcA and the Company will receive clinical development and commercialization rights in the rest of world (excluding South Korea) and manufacturing development and manufacturing rights worldwide (including South Korea) The eliminates the profit-sharing arrangement in the Original ISU Abxis Agreement and rovides for a low single-digit royalty payment to ISU Abxis, on a country-by-country basis, for net product sales of DalcA by the Company or its affiliates in each country other than South Korea. Pursuant to the A&R , the Company will also pay up to an aggregate of $19.5 million in milestone payments to ISU Abxis, including $2.5 million in regulatory and development milestone payments and up to $17 million in commercial milestone payments, if the applicable milestones are met.

Net Loss per Share Attributable

Net Loss per Share Attributable to Common Stockholders	9 Months Ended
	Sep. 30, 2019
Earnings Per Share [Abstract]
Net Loss per Share Attributable to Common Stockholders	8. The following table sets forth the computation of the basic and diluted net loss per common share during the nine months ended September 30, 2019 and 2018 ( in thousands, except share and per share data Three Months Ended September 30, Nine Months Ended September 30, 2019 2018 2019 2018 Net loss attributable to common stockholders $ (12,706 ) $ (7,694 ) $ (41,568 ) $ (19,218 ) Weighted-average number of shares used in computing net loss per share, basic and diluted 12,022,620 11,942,729 11,992,240 10,967,750 Net loss available for common stockholders per share, basic and diluted $ (1.06 ) $ (0.64 ) $ (3.47 ) $ (1.75 ) Since the Company was in a loss position for all periods presented, diluted net loss per share is the same as basic net loss per share for all periods as the inclusion of all potential common shares outstanding would have been anti-dilutive. Potentially dilutive securities on an as-if converted basis that were not included in the diluted per share calculations because they would be anti-dilutive were as follows: Nine Months Ended September 30, 2019 2018 Options to purchase common stock 1,569,838 1,319,102 Common stock warrants 7,857 12,039 Total 1,577,695 1,331,141

Stockholders' Equity

Stockholders' Equity	9 Months Ended
	Sep. 30, 2019
Equity [Abstract]
Stockholders' Equity	9. Stockholders’ Equity February 2018 Underwritten Public Offering — On February 13, 2018, the Company entered into an underwriting agreement with JonesTrading, in connection with a registered firm commitment underwritten public offering of 2,941,176 shares of common stock, pursuant to a shelf registration statement that was declared effective by the SEC on February 6, 2018. On February 15, 2018, the Company sold 3,382,352 shares of common stock (including 441,176 shares of common stock sold pursuant to the exercise of the underwriters’ overallotment option) at a price to the public of $34.00 per share. The net proceeds to the Company, after deducting the underwriting discounts and commissions and offering expenses payable by the Company were approximately $106.8 million.

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2019
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	10. Commitments and Contingencies Manufacturing Agreements On May 20, 2016, the Company signed a development and manufacturing services agreement with AGC Biologics, Inc. (“AGC”), formerly known as CMC ICOS Biologics, Inc., pursuant to which AGC will conduct manufacturing development of agreed upon product candidates. The Company currently has firm work orders with AGC to manufacture MarzAA and DalcA to support its clinical trials totaling $12.4 million and the payment obligations remaining at September 30, 2019 was $5.4 million.

Related Parties

Related Parties	9 Months Ended
	Sep. 30, 2019
Related Party Transactions [Abstract]
Related Parties	11. Related Parties On October 24, 2017, the Company announced a strategic research collaboration with Mosaic Biosciences, Inc. (“Mosaic”) to develop intravitreal anti-complement factor 3 products for the treatment of dry age-related macular degeneration and other retinal diseases. According to the agreement the Company and Mosaic will co-fund the research. Dr. Usman, the Company’s Chief Executive Officer and a member of the Company’s board of directors, and Mr. Lawlor, the chairman of the Company’s board of directors, were also members of the board of directors of Mosaic when this agreement was entered in to, and the agreement was reviewed by disinterested members of the Company’s board of directors and approved by the Company’s audit committee. Expenses related to the collaboration were $0.3 and $0.5 million for the three months ended September 30, 2019 and 2018, respectively. Expenses related to the collaboration were $0.8 and $0.9 million for the nine months ended September 30, 2019 and 2018, respectively.

Interest and Other Income

Interest and Other Income	9 Months Ended
	Sep. 30, 2019
Other Income And Expenses [Abstract]
Interest and Other Income	12. Interest and Other Income The following table shows the detail of interest and other income/(expense), net for the three-and nine-months ended September 30, 2019 and 2018 ( in thousands Three Months Ended September 30, Nine Months Ended September 30, 2019 2018 2019 2018 Interest income $ 489 $ 652 $ 1,763 $ 1,539 Loss on disposal of fixed assets — — — (116 ) Other income/(expense), net — (1 ) (41 ) 1,497 Total other income/(expense), net $ 489 $ 651 $ 1,722 $ 2,920 Other income of $1.5 million for the nine months ended September 30, 2018 reflects milestone payments received under an agreement associated with neuronal nicotinic receptor assets sold in 2016.

Subsequent Event

Subsequent Event	9 Months Ended
	Sep. 30, 2019
Subsequent Events [Abstract]
Subsequent Event	13. Subsequent Event On October 9, 2019, the Company and Catalent Indiana, LLC (“Catalent”) signed a clinical supply services agreement, effective October 4, 2019, pursuant to which Catalent will conduct drug product development of agreed upon product candidates. The Company has no firm work orders with Catalent at September 30, 2019.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2019
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The Company’s condensed consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (“GAAP”) and following the requirements of the Securities and Exchange Commission (the “SEC”) for interim reporting. As permitted under those rules, certain footnotes or other financial information that are normally required by GAAP can be condensed or omitted. These financial statements have been prepared on the same basis as the Company’s annual financial statements and, in the opinion of management, reflect all adjustments, consisting only of normal recurring adjustments, which are necessary for a fair presentation of the Company’s financial information. These interim results and cash flows for any interim period are not necessarily indicative of the results to be expected for the full year. The accompanying condensed consolidated financial statements and related financial information should be read in conjunction with the consolidated financial statements filed with the Company’s Annual Report on Form 10-K for the year ended December 31, 2018 (“Annual Report”).
Accounting Pronouncements Recently Adopted	Accounting Pronouncements Recently Adopted The Company’s significant accounting policies are included in “Part II - Item 8 - Financial Statements and Supplementary Data - Note 3 – Summary of Significant Accounting Policies” in the Company’s Annual Report. In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842), to enhance the transparency and comparability of financial reporting related to leasing arrangements. The Company adopted the standard effective January 1, 2019. There have been no other significant changes to these accounting policies during the first nine months of 2019. At the inception of an arrangement, the Company determines whether the arrangement is or contains a lease based on the unique facts and circumstances present. Operating lease liabilities and their corresponding right-of-use assets are recorded based on the present value of lease payments over the expected lease term. The interest rate implicit in lease contracts is typically not readily determinable. As such, the Company utilizes its incremental borrowing rate, which is the rate incurred to borrow on a collateralized basis over a similar term an amount equal to the lease payments in a similar economic environment. Certain adjustments to the right-of-use asset may be required for items such as initial direct costs paid or incentives received. The Company has elected to combine lease and non-lease components as a single component. The lease expense is recognized over the expected term on a straight-line basis. Operating leases are recognized on the balance sheet as right-of-use assets, operating lease liabilities, current and operating lease liabilities, non-current. As a result, the Company no longer recognizes deferred rent on the balance sheet. On January 1, 2019, the Company adopted the new lease accounting standard using the optional transition method under which comparative financial information is not restated and continues to apply the provisions of the previous lease accounting standard in its financial disclosures for the comparative periods. The Company also elected relevant optional practical expedients including that the Company did not (1) reassess whether expired or existing contracts are or contain a lease, (2) reassess the lease classifications or reassess the initial direct costs associated with expired or existing leases, and (3) separate lease and non-lease components of its operating leases in which it is the lessee. The adoption of the new lease accounting standard had an impact of approximately $2.1 million on the Company's assets and liabilities and had no impact on cash provided by or used in operating, investing or financing activities on the Company's condensed consolidated statements of cash flows. The adoption of the new lease accounting standard did not impact previously reported financial results.
Investments	Investments The Company invests its excess cash in investment grade, short to intermediate-term, fixed income securities and recognizes purchased securities on the settlement date. All investments have been classified as “available-for-sale” and are carried at estimated fair value based upon quoted market prices or pricing models for similar securities. Management determines the appropriate classification of its investments at the time of purchase and reevaluates such designation as of each balance sheet date. Unrealized gains and losses are excluded from earnings and are reported as a component of comprehensive loss. Realized gains and losses and declines in fair value determined to be other-than-temporary, if any, on available-for-sale securities are included in interest and other income. The cost of securities sold is based on the specific-identification method. Interest on short-term investments is included in interest and other income.

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2019
Fair Value Disclosures [Abstract]
Assets and Liabilities Measured at Fair Value on a Recurring Basis	There were no transfers in or out of Level 1 or 2 during the periods presented. The following tables present the fair value hierarchy for assets and liabilities measured at fair value on a recurring basis as of September 30, 2019 and December 31, 2018 ( in thousands September 30, 2019 Level 1 Level 2 Level 3 Total Financial assets: Money market funds (1) $ 21,752 $ — $ — $ 21,752 U.S. government agency securities (2) 48,453 — — 48,453 Federal agency securities (2) — 13,479 — 13,479 Total financial assets $ 70,205 $ 13,479 $ — $ 83,684 (1) Included in cash and cash equivalents on the accompanying condensed consolidated balance sheets. ( 2 ) Included in short-term investments on the accompanying condensed consolidated balance sheets and are classified as available-for-sale securities. December 31, 2018 Level 1 Level 2 Level 3 Total Financial assets: Money market funds (1) $ 29,090 $ — $ — $ 29,090 Federal agency securities (1) — 999 — 999 U.S. Treasury securities (2) 74,139 74,139 Federal agency securities (2) 14,775 — 14,775 Restricted cash (money market funds) 50 — — 50 Total financial assets $ 103,279 $ 15,774 $ — $ 119,053 (1) Included in cash and cash equivalents on the accompanying condensed consolidated balance sheets. ( 2 ) Included in short-term investments on the accompanying condensed consolidated balance sheets and are classified as available-for-sale securities.

Financial Instruments (Tables)

Financial Instruments (Tables)	9 Months Ended
	Sep. 30, 2019
Investments All Other Investments [Abstract]
Cash Equivalents, Restricted Cash and Short-Term Investments Classified as Available-for-sale Securities	Cash equivalents, restricted cash and short-term investments (debt securities) which are classified as available-for-sale securities, consisted of the following ( in thousands September 30, 2019 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Money market funds (cash equivalents) $ 21,752 $ — $ — $ 21,752 U.S. government agency securities 48,439 14 — 48,453 Federal agency securities 13,462 17 — 13,479 Total financial assets $ 83,653 $ 31 $ — $ 83,684 Classified as: Cash and cash equivalents $ 21,752 Short-term investments 61,932 $ 83,684 December 31, 2018 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Money market funds (cash equivalents) $ 29,090 $ — $ — $ 29,090 Federal agency securities (cash equivalents) 999 — — 999 Restricted cash (money market funds) 50 — — 50 U.S. government agency securities 74,144 1 (6 ) 74,139 Agency securities 14,774 1 — 14,775 Total financial assets $ 119,057 $ 2 $ (6 ) $ 119,053 Classified as: Cash and cash equivalents $ 30,089 Short-term investments 88,914 Restricted cash (money market funds) 50 $ 119,053

Lease (Tables)

Lease (Tables)	9 Months Ended
	Sep. 30, 2019
Lessee Disclosure [Abstract]
Summary of Present Value Assumptions used in Calculating Present Value of Lease Payments	The present value assumptions used in calculating the present value of the lease payments were as follows: Weighted-average remaining lease term 3.6 years Weighted-average discount rate 6.0 %
Summary of Future Lease Payments under Non-cancelable Leases	Future lease payments under non-cancelable leases as of September 30, 2019 were as follows (in thousands) Remaining in 2019 $ 141 2020 578 2021 596 2022 613 2023 209 Total future minimum lease payments 2,137 Less imputed interest (222 ) Total lease liability $ 1,915
Schedule of Supplemental Cash Flow Information	Supplemental cash flow information for the nine months ended September 30, 2019 related to operating leases was as follows (in thousands) Cash paid for leases that were included in operating cash outflows $ 420

Stock Based Compensation (Table

Stock Based Compensation (Tables)	9 Months Ended
	Sep. 30, 2019
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Summary of Option Activity Under Company's Equity Incentive Plans	The following table summarizes stock option activity under the Company’s equity incentive plans and related information: Number of Shares Underlying Outstanding Options Weighted- Average Exercise Price Weighted- Average Remaining Contractual Term (Years) Outstanding — December 31, 2018 1,361,977 $ 12.04 8.71 Options granted 426,500 $ 8.00 Options exercised (41,219 ) $ 4.57 Options forfeited (166,722 ) $ 8.27 Options expired (10,698 ) $ 92.53 Outstanding — September 30, 2019 1,569,838 $ 10.99 8.38 Exercisable — September 30, 2019 649,116 $ 14.14 7.86 Vested and expected to vest — September 30, 2019 1,569,838 $ 10.99 8.38
Summary of Weighted Average Valuation Assumptions Used to Estimate Fair Value of Employee Stock Options	The fair value of employee stock options was estimated using the following weighted-average assumptions for the nine months ended September 30, 2019 and 2018: Nine Months Ended September 30, 2019 2018 Employee Stock Options: Risk-free interest rate 2.39 % 2.66 % Expected term (in years) 5.98 5.97 Dividend yield — — Volatility 89.76 % 93.60 % Weighted-average fair value of stock options granted $ 5.93 $ 10.28
Summary of Stock-Based Compensation Recognized	Total stock-based compensation recognized was as follows ( in thousands Three Months Ended September 30, Nine Months Ended September 30, 2019 2018 2019 2018 Research and development $ 284 $ 161 $ 805 $ 418 General and administrative (1) 517 541 1,728 1,448 Total stock-based compensation $ 801 $ 702 $ 2,533 $ 1,866 (1) Included $0.03 and $0.1 million related to modifications of certain Board member stock options in the nine months ended September 30, 2019 and 2018, respectively. These modifications extended the post-termination exercise period of certain options.

Net Loss per Share Attributab_2

Net Loss per Share Attributable to Common Stockholders (Tables)	9 Months Ended
	Sep. 30, 2019
Earnings Per Share [Abstract]
Basic and Diluted Net Loss Per Common Share	The following table sets forth the computation of the basic and diluted net loss per common share during the nine months ended September 30, 2019 and 2018 ( in thousands, except share and per share data Three Months Ended September 30, Nine Months Ended September 30, 2019 2018 2019 2018 Net loss attributable to common stockholders $ (12,706 ) $ (7,694 ) $ (41,568 ) $ (19,218 ) Weighted-average number of shares used in computing net loss per share, basic and diluted 12,022,620 11,942,729 11,992,240 10,967,750 Net loss available for common stockholders per share, basic and diluted $ (1.06 ) $ (0.64 ) $ (3.47 ) $ (1.75 )
Anti-dilutive Security not Included In Diluted per Share Calculations	Since the Company was in a loss position for all periods presented, diluted net loss per share is the same as basic net loss per share for all periods as the inclusion of all potential common shares outstanding would have been anti-dilutive. Potentially dilutive securities on an as-if converted basis that were not included in the diluted per share calculations because they would be anti-dilutive were as follows: Nine Months Ended September 30, 2019 2018 Options to purchase common stock 1,569,838 1,319,102 Common stock warrants 7,857 12,039 Total 1,577,695 1,331,141

Interest and Other Income (Tabl

Interest and Other Income (Tables)	9 Months Ended
	Sep. 30, 2019
Other Income And Expenses [Abstract]
Detail of Interest and Other Income/(Expense), Net	The following table shows the detail of interest and other income/(expense), net for the three-and nine-months ended September 30, 2019 and 2018 ( in thousands Three Months Ended September 30, Nine Months Ended September 30, 2019 2018 2019 2018 Interest income $ 489 $ 652 $ 1,763 $ 1,539 Loss on disposal of fixed assets — — — (116 ) Other income/(expense), net — (1 ) (41 ) 1,497 Total other income/(expense), net $ 489 $ 651 $ 1,722 $ 2,920

Nature of Operations - Addition

Nature of Operations - Additional Information (Detail) $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2019USD ($)	Jun. 30, 2019USD ($)	Mar. 31, 2019USD ($)	Sep. 30, 2018USD ($)	Jun. 30, 2018USD ($)	Mar. 31, 2018USD ($)	Sep. 30, 2019USD ($)Segment	Sep. 30, 2018USD ($)	Dec. 31, 2018USD ($)
Accounting Policies [Abstract]
Number of operating segment | Segment							1
Net loss	$ 12,706	$ 13,780	$ 15,082	$ 7,694	$ 6,482	$ 5,042	$ 41,568	$ 19,218
Accumulated deficit	244,910						244,910		$ 203,342
Cash, cash equivalents, and short-term investments	$ 85,000						$ 85,000

Summary of Significant Accoun_3

Summary of Significant Accounting Policies - Additional Information (Detail) $ in Millions	9 Months Ended
	Sep. 30, 2019USD ($)
Accounting Standards Update 2016-02 Leases (Topic 842)
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Impact of new lease accounting standard on assets and liabilities	$ 2.1

Assets and Liabilities Measured

Assets and Liabilities Measured at Fair Value (Detail) - USD ($) $ in Thousands		Sep. 30, 2019	Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value		$ 83,684	$ 119,053
Money Market Funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value	[1]	21,752	29,090
Restricted cash (money market funds)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value			50
U.S. Government Agency Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value	[2]	48,453
Federal Agency Securities | Short-Term Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value	[2]	13,479	14,775
Federal Agency Securities | Cash and Cash Equivalents
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value	[1]		999
US Treasury Securities | Short-Term Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value	[2]		74,139
Fair Value, Inputs, Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value		70,205	103,279
Fair Value, Inputs, Level 1 | Money Market Funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value	[1]	21,752	29,090
Fair Value, Inputs, Level 1 | Restricted cash (money market funds)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value			50
Fair Value, Inputs, Level 1 | U.S. Government Agency Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value	[2]	48,453
Fair Value, Inputs, Level 1 | US Treasury Securities | Short-Term Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value	[2]		74,139
Fair Value, Inputs, Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value		13,479	15,774
Fair Value, Inputs, Level 2 | Federal Agency Securities | Short-Term Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value	[2]	$ 13,479	14,775
Fair Value, Inputs, Level 2 | Federal Agency Securities | Cash and Cash Equivalents
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value	[1]		$ 999
[1]	Included in cash and cash equivalents on the accompanying condensed consolidated balance sheets.
[2]	Included in short-term investments on the accompanying condensed consolidated balance sheets and are classified as available-for-sale securities.

Cash Equivalents, Restricted Ca

Cash Equivalents, Restricted Cash and Short-Term Investments Classified as Available-for-sale Securities (Detail) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 83,653	$ 119,057
Gross Unrealized Gains	31	2
Gross Unrealized Losses		(6)
Estimated Fair Value	83,684	119,053
Money Market Funds | Cash Equivalents
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	21,752	29,090
Estimated Fair Value	21,752	29,090
Money Market Funds | Restricted cash
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		50
Estimated Fair Value		50
U.S. Government Agency Securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	48,439	74,144
Gross Unrealized Gains	14	1
Gross Unrealized Losses		(6)
Estimated Fair Value	48,453	74,139
Cash and Cash Equivalents
Schedule of Available-for-sale Securities [Line Items]
Estimated Fair Value	21,752	30,089
Short-Term Investments
Schedule of Available-for-sale Securities [Line Items]
Estimated Fair Value	61,932	88,914
Federal Agency Securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	13,462
Gross Unrealized Gains	17
Estimated Fair Value	$ 13,479
Federal Agency Securities | Cash Equivalents
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		999
Estimated Fair Value		999
Agency Securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		14,774
Gross Unrealized Gains		1
Estimated Fair Value		$ 14,775

Financial Instruments - Additio

Financial Instruments - Additional Information (Detail)	9 Months Ended
	Sep. 30, 2019USD ($)
Financial Instrument [Line Items]
Material realized gains or losses on available-for-sale securities	$ 0
Maximum
Financial Instrument [Line Items]
Available for sale debt securities contractual maturities	1 year

Lease - Additional Information

Lease - Additional Information (Detail) $ in Millions	9 Months Ended
	Sep. 30, 2019USD ($)
Lessee Disclosure [Abstract]
Lease expiration date	Apr. 30, 2023
Lessee operating lease renewal term description	no stated renewal options
Operating lease expense	$ 0.5

Summary of Present Value Assump

Summary of Present Value Assumptions used in Calculating Present Value of Lease Payments (Detail)	Sep. 30, 2019
Lessee Disclosure [Abstract]
Weighted-average remaining lease term	3 years 7 months 6 days
Weighted-average discount rate	6.00%

Summary of Future Lease Payment

Summary of Future Lease Payments under Non-cancelable Leases (Detail)	Sep. 30, 2019USD ($)
Operating Lease Liabilities Payments Due [Abstract]
Remaining in 2019	$ 141
2020	578
2021	596
2022	613
2023	209
Total future minimum lease payments	2,137
Less imputed interest	(222)
Total lease liability	$ 1,915

Schedule of Supplemental Cash F

Schedule of Supplemental Cash Flow Information (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2019USD ($)
Operating Lease Liabilities Payments Due [Abstract]
Cash paid for leases that were included in operating cash outflows	$ 420

Summary of Option Activity Unde

Summary of Option Activity Under Company's Equity Incentive Plans (Detail) - $ / shares	9 Months Ended	12 Months Ended
	Sep. 30, 2019	Dec. 31, 2018
Number of Shares Underlying Outstanding Options
Number of Shares Underlying Outstanding Options, Beginning Balance	1,361,977
Number of Shares Underlying Outstanding Options, Options granted	426,500
Number of Shares Underlying Outstanding Options, Options exercised	(41,219)
Number of Shares Underlying Outstanding Options, Options forfeited	(166,722)
Number of Shares Underlying Outstanding Options, Options expired	(10,698)
Number of Shares Underlying Outstanding Options, Ending Balance	1,569,838	1,361,977
Number of Shares Underlying Outstanding Options, Exercisable - June 30, 2019	649,116
Number of Shares Underlying Outstanding Options, Vested and expected to vest - June 30, 2019	1,569,838
Weighted- Average Exercise Price
Weighted- Average Exercise Price, Beginning Balance	$ 12.04
Weighted- Average Exercise Price, Options granted	8
Weighted- Average Exercise Price, Options exercised	4.57
Weighted- Average Exercise Price, Options forfeited	8.27
Weighted- Average Exercise Price, Options expired	92.53
Weighted- Average Exercise Price, Ending Balance	10.99	$ 12.04
Weighted- Average Exercise Price, Exercisable - June 30, 2019	14.14
Weighted- Average Exercise Price, Vested and expected to vest - June 30, 2019	$ 10.99
Weighted-Average Remaining Contractual Term (Years)
Weighted-Average Remaining Contractual Term (Years), Outstanding Balance	8 years 4 months 17 days	8 years 8 months 15 days
Weighted-Average Remaining Contractual Term (Years), Exercisable - June 30, 2019	7 years 10 months 9 days
Weighted-Average Remaining Contractual Term (Years), Vested and expected to vest - June 30, 2019	8 years 4 months 17 days

Stock Based Compensation - Addi

Stock Based Compensation - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2019	Sep. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares of common stock issued to certain board members in lieu of cash compensation	7,393	13,392
Number of common stock available for future grant	1,032,672	1,032,672
Shares remaining outstanding	1,569,838	1,569,838
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term of stock options		5 years 11 months 23 days	5 years 11 months 19 days
Unrecognized employee stock based compensation expense	$ 5.9	$ 5.9
Unrecognized employee stock based compensation expense, period for recognition		2 years 7 months 6 days

Fair Values of Stock Options Es

Fair Values of Stock Options Estimated Using Black-Scholes Valuation Model (Detail) - Employee Stock Option - $ / shares	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Black Scholes Method Used [Line Items]
Risk-free interest rate	2.39%	2.66%
Expected term (in years)	5 years 11 months 23 days	5 years 11 months 19 days
Dividend yield	0.00%	0.00%
Volatility	89.76%	93.60%
Weighted-average fair value of stock options granted	$ 5.93	$ 10.28

Summary of Stock-Based Compensa

Summary of Stock-Based Compensation Recognized (Detail) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation		$ 801	$ 702	$ 2,533	$ 1,866
Research and development
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation		284	161	805	418
General and Administrative
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation	[1]	$ 517	$ 541	$ 1,728	$ 1,448
[1]	Included $0.03 and $0.1 million related to modifications of certain Board member stock options in the nine months ended September 30, 2019 and 2018, respectively. These modifications extended the post-termination exercise period of certain options.

Summary of Stock-Based Compen_2

Summary of Stock-Based Compensation Recognized (Parenthetical) (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Modification of stock options, expense	$ 801	$ 702	$ 2,533	$ 1,866
Board Member Stock Options
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Modification of stock options, expense			$ 30	$ 100

Collaborations - Additional Inf

Collaborations - Additional Information (Detail) - USD ($)	1 Months Ended		9 Months Ended
	Dec. 31, 2018	Feb. 28, 2018	Sep. 30, 2019	Dec. 08, 2016
Pfizer Inc | Collaboration Agreement
Revenue Recognition Multiple Deliverable Arrangements [Line Items]
Milestone payment		$ 1,000,000	$ 0
Pfizer Inc | Collaboration Agreement | Maximum
Revenue Recognition Multiple Deliverable Arrangements [Line Items]
Contingent cash payments upon achievement of certain clinical, regulatory and commercial milestones				$ 17,500,000
ISU Abxis | Amended and Restated License Agreement
Revenue Recognition Multiple Deliverable Arrangements [Line Items]
Regulatory and development milestone payment	$ 2,500,000
ISU Abxis | Amended and Restated License Agreement | Maximum
Revenue Recognition Multiple Deliverable Arrangements [Line Items]
Milestone payment	19,500,000
Commercial milestone payments	$ 17,000,000

Basic and Diluted Net Loss Per

Basic and Diluted Net Loss Per Common Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Earnings Per Share [Abstract]
Net loss attributable to common stockholders	$ (12,706)	$ (7,694)	$ (41,568)	$ (19,218)
Weighted-average number of shares used in computing net loss per share, basic and diluted	12,022,620	11,942,729	11,992,240	10,967,750
Net loss available for common stockholders per share, basic and diluted	$ (1.06)	$ (0.64)	$ (3.47)	$ (1.75)

Anti-dilutive Security not Incl

Anti-dilutive Security not Included In Diluted per Share Calculations (Detail) - shares	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti dilutive securities	1,577,695	1,331,141
Options To Purchase Common Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti dilutive securities	1,569,838	1,319,102
Common Stock Warrants
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti dilutive securities	7,857	12,039

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions	Feb. 15, 2018	Feb. 13, 2018	Mar. 31, 2018
Stockholders Equity Disclosure [Line Items]
Net proceeds from sale of common stock	$ 106.8
Common Stock
Stockholders Equity Disclosure [Line Items]
Firm commitment underwritten public offering shares		2,941,176
Issuance of stock, shares	3,382,352		3,382,352
Common stock price, per share	$ 34
Common Stock | Overallotment Option
Stockholders Equity Disclosure [Line Items]
Issuance of stock, shares	441,176

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Detail) - AGC Biologics, Inc - Marzeptacog Alfa Activated and Dalcinonacog Alfa $ in Millions	Sep. 30, 2019USD ($)
Commitments And Contingencies Disclosure [Line Items]
Clinical trials	$ 12.4
Contractual obligation payments	$ 5.4

Related Parties - Additional In

Related Parties - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Mosaic | Collaboration Agreement | Intravitreal Anti-Complement Factor 3
Related Party Transaction [Line Items]
Expenses related to collaboration	$ 0.3	$ 0.5	$ 0.8	$ 0.9

Detail of Interest and Other In

Detail of Interest and Other Income/(Expense), Net (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Other Income And Expenses [Abstract]
Interest income	$ 489	$ 652	$ 1,763	$ 1,539
Loss on disposal of fixed assets				(116)
Other income/(expense), net		(1)	(41)	1,497
Total other income/(expense), net	$ 489	$ 651	$ 1,722	$ 2,920

Interest and Other Income - Add

Interest and Other Income - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Other Income And Expenses [Abstract]
Other income reflects milestone payments received	$ (1)	$ (41)	$ 1,497