0000950170-23-061493 | 10-Q | XBRL Viewer

Net Loss per Share (Tables)

9 Months Ended

Sep. 30, 2023

Schedule of Potentially Common Shares Excluded from Calculation of Net Loss Per share

The following potential common shares, presented based on amounts outstanding at each period end, were excluded from the calculation of the diluted net loss per share attributable to common stockholders for the period indicated because including them would have had an anti-dilutive effect.


	As of September 30,
	2023		2022
Unvested restricted common stock awards		41,798		43,951
Outstanding options to purchase common stock		653,927		491,151
Potential shares issuable under the ESPP		—		—

Property and Equipment, Net

9 Months Ended

Sep. 30, 2023

Property, Plant and Equipment [Abstract]

Property and Equipment, Net

(5)

Property and Equipment, net

Property and equipment, net consists of the following (in thousands):


	September 30,			December 31,
	2023			2022
Laboratory equipment	$	9,350		$	9,313
Computer and office equipment		793			793
Furniture and fixtures		500			500
Leasehold improvements		9,820			9,820
Construction in progress		135			37
		20,598			20,463
Less accumulated depreciation		(14,649	)		(13,140	)
Property and equipment, net	$	5,949		$	7,323

Document and Entity Information - shares	9 Months Ended
Document and Entity Information - shares	Sep. 30, 2023	Nov. 02, 2023
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2023
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	Q3
Trading Symbol	SYBX
Entity Registrant Name	SYNLOGIC, INC.
Security Exchange Name	NASDAQ
Entity Central Index Key	0001527599
Entity Current Reporting Status	Yes
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Shell Company	false
Entity Small Business	true
Entity Emerging Growth Company	false
Title of 12(b) Security	Common Stock, par value $0.001 per share
Entity Common Stock, Shares Outstanding		9,189,353
Entity Address, State or Province	MA
Entity File Number	001-37566
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	26-1824804
Entity Address, Address Line One	301 Binney St.
Entity Address, Address Line Two	Suite 402
Entity Address, City or Town	Cambridge
Entity Address, Postal Zip Code	02142
City Area Code	617
Local Phone Number	401-9975
Entity Interactive Data Current	Yes
Document Quarterly Report	true
Document Transition Report	false

Collaboration Agreements - Additional Information (Detail) - USD ($)	1 Months Ended	3 Months Ended		9 Months Ended
	Jun. 30, 2019	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Recognition of revenue		$ 393,000	$ 678,000	$ 602,000	$ 1,074,000
Current deferred revenue		264,000		264,000		$ 882,000
Ginkgo Collaboration
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Prepayment to related party for collaboration agreement	$ 30,000,000
Related party transaction collaboration agreement, initial term	5 years
Related Party Transaction Collaboration Agreement Initial Term Extended	3 years
Current pre-paid research and development		0.8		0.8
Non-current pre-paid research and development		5.2		5.2
Roche Collaboration and Option Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Recognition of revenue				600,000	$ 1,100,000
Roche Collaboration and Option Agreement \| Current Liabilities
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Current deferred revenue		$ 300,000		$ 300,000

Equity based Compensation - Schedule of Equity-based Compensation Expenses by Award Type (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Equity-based compensation expense	$ 640	$ 894	$ 2,003	$ 2,761
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Equity-based compensation expense	509	764	1,656	2,429
Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Equity-based compensation expense	93	111	280	277
ESPP
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Equity-based compensation expense	$ 38	$ 19	$ 67	$ 55

Stockholders' Equity

9 Months Ended

Sep. 30, 2023

Equity [Abstract]

Stockholders' Equity

(7)

Stockholders’ Equity

Reverse Stock Split

On September 27, 2023, the Company effected a reverse stock split of its shares of common stock, pursuant to which every fifteen (15) shares of the its issued and outstanding common stock was automatically converted into one (1) issued and outstanding share of common stock without any change in the par value of $0.001 per share. The reverse stock split was approved by the stockholders on September 21, 2023 at a special meeting of stockholders.

In June 2019, the Company issued to Ginkgo Bioworks, Inc. (Ginkgo) an aggregate of 422,718 shares of common stock at a purchase price per share of $135, and pre-funded warrants (the Ginkgo pre-funded warrants) to purchase up to an aggregate of 169,874 shares of common stock at an exercise price of $135 per share, with $134.85 of such exercise price paid at the closing of the offering. The net proceeds to the Company were approximately $79.9 million. None of the Ginkgo pre-funded warrants have been exercised as of September 30, 2023. (See Note 9, Collaboration Agreements: Ginkgo Collaboration). The shares of common stock and the Ginkgo pre-funded warrants to purchase common stock were adjusted, as a result of the reverse stock split, during the three and nine months ended September 30, 2023.

In July 2021, the Company entered into a sales agreement with Jefferies, LLC (Jefferies) with respect to an at-the-market (ATM) offering program. In an ATM offering, exchange-listed companies incrementally sell newly issued shares into the secondary trading market through a designated broker-dealer at prevailing market prices. Under the ATM offering program, the Company may offer and sell, from time to time at its sole discretion, shares of its common stock having aggregate sales proceeds of up to $50.0 million. Jefferies is not required to sell any specific amount of common stock but acts as the Company’s sales agent using commercially reasonable efforts consistent with its normal trading and sales practices. During the nine months ended September 30, 2023, 115,966 shares of common stock were sold pursuant to the sales agreement with Jefferies, resulting in net proceeds of approximately $1.25 million.

The Company has reserved for future issuance the following shares of common stock related to the potential exercise of Ginkgo pre-funded warrants, exercise of stock options, and the employee stock purchase plan:


	September 30, 2023
Common stock issuable under Ginkgo pre-funded warrants		169,874
Options exercisable to purchase common stock		292,805
Employee Stock Purchase Plan		—
Total		462,679

- Definition

The entire disclosure for equity.

+ References

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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
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Reference 11: http://www.xbrl.org/2003/role/disclosureRef
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Reference 13: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Net Loss per Share

9 Months Ended

Sep. 30, 2023

Earnings Per Share [Abstract]

Net Loss per Share

(10)

Net Loss per Share

Basic net loss per share is computed using the weighted-average number of shares of common stock outstanding during the period. Diluted net loss per share is computed using the sum of the weighted-average number of shares of common stock outstanding during the period and if dilutive, the weighted-average number of potential shares of common stock, including unvested restricted common stock and outstanding stock options. In June 2019, the Company sold 422,718 shares of common stock and pre-funded warrants to purchase an aggregate of 169,874 shares of common stock at an exercise price of $135 per share, with $134.85 of such exercise price paid at the closing of the offering (see Note 8, Stockholder's Equity and Note 10, Collaborations: Ginkgo Collaboration, in the audited financial statements included in the 2022 Annual Report). The shares of common stock and the Ginkgo pre-funded warrants to purchase common stock were adjusted, as a result of the reverse stock split, during the three months ended September 30, 2023. The shares of common stock into which the warrants may be exercised are considered outstanding for the purposes of computing net loss per share.

The Company’s potentially dilutive shares, which include outstanding stock options, unvested restricted common stock and potential shares issuable under the ESPP, are considered to be common share equivalents and are only included in the calculation of diluted net loss per share when their effect is dilutive.


	As of September 30,
	2023		2022
Unvested restricted common stock awards		41,798		43,951
Outstanding options to purchase common stock		653,927		491,151
Potential shares issuable under the ESPP		—		—

Available-for-Sale Securities

9 Months Ended

Sep. 30, 2023

Investments, Debt and Equity Securities [Abstract]

Available-for-Sale Securities

(4)

Available-for-Sale Securities

The following tables summarize the available-for-sale securities held at September 30, 2023 and December 31, 2022 (in thousands):


September 30, 2023	Amortized cost		Gross unrealized gains		Gross unrealized losses			Fair Value
Commercial paper	$	2,472	$	—	$	—		$	2,472
U.S. government agency securities and treasuries		6,403		4		—			6,407
Total	$	8,875	$	4	$	—		$	8,879

December 31, 2022	Amortized cost		Gross unrealized gains		Gross unrealized losses			Fair Value
Commercial paper	$	44,437	$	8	$	(70	)	$	44,375
U.S. treasuries		17,492		—		(99	)		17,393
Total	$	61,929	$	8	$	(169	)	$	61,768

All securities held by the Company at September 30, 2023 had contractual maturities of four months or less and none of such securities were in an unrealized loss position. There were fifteen investments in an unrealized loss position at December 31, 2022, none of which had been in an unrealized loss position for more than twelve months. The aggregate fair value of the securities in an unrealized loss position at December 31, 2022 was $36.6 million. The Company reviews its investments for other-than-temporary impairment whenever the fair value of an investment is less than amortized cost and evidence indicates that an investment’s carrying amount is not recoverable within a reasonable period of time. To determine whether an impairment is other-than-temporary, the Company considers whether it has the ability and intent to hold the investment until a market price recovery and considers whether evidence indicating the cost of the investment is recoverable outweighs evidence to the contrary.

Gross realized gains and losses on the sales of investments have not been material to the Company’s consolidated statement of operations.

Available-for-Sale Securities (Tables)

9 Months Ended

Sep. 30, 2023

Investments, Debt and Equity Securities [Abstract]

Summary of Available-for-Sale Securities Held

The following tables summarize the available-for-sale securities held at September 30, 2023 and December 31, 2022 (in thousands):


September 30, 2023	Amortized cost		Gross unrealized gains		Gross unrealized losses			Fair Value
Commercial paper	$	2,472	$	—	$	—		$	2,472
U.S. government agency securities and treasuries		6,403		4		—			6,407
Total	$	8,875	$	4	$	—		$	8,879

December 31, 2022	Amortized cost		Gross unrealized gains		Gross unrealized losses			Fair Value
Commercial paper	$	44,437	$	8	$	(70	)	$	44,375
U.S. treasuries		17,492		—		(99	)		17,393
Total	$	61,929	$	8	$	(169	)	$	61,768

Equity based Compensation - Additional Information (Detail) - USD ($)		9 Months Ended
	Jan. 01, 2023	Sep. 30, 2023
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of stock options granted		303,810
Weighted average exercise price		$ 9.31
Employee unrecognized compensation expense		$ 3,900,000
Employee unrecognized compensation cost, period of recognition		2 years 3 months
Restricted Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employee unrecognized compensation expense		$ 0.8
Employee unrecognized compensation cost, period of recognition		2 years 2 months 12 days
Number of restricted stock awards granted		10,803
Weighted average grant date fair value		$ 9.3
ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Increase in number of shares available for issuance (in shares)	44,490
Shares available for future grants		95,134
Plan 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Increase in number of shares available for issuance (in shares)	222,454
2017 Plan and 2015 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for future grants		175,874

Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) $ in Thousands	Total	Common Stock $0.001 Par Value	Additional Paid-in Capital	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit	Treasury Stock, Common [Member]
Balance at Dec. 31, 2021	$ 147,266	$ 5	$ 438,178	$ (45)	$ (290,872)
Balance (in Shares) at Dec. 31, 2021		4,646,590
Exercise of options	61		61
Exercise of options, shares		2,370
Issuance of common stock under employee stock purchase plan	137		137
Issuance of common stock under employee stock purchase plan, Shares		7,108
Issuance of restricted stock, shares		33,817
Cancellation of restricted stock		(4,187)
Equity-based compensation expense	2,761		2,761
Unrealized gain (loss) on securities	(346)			(346)
Net loss	(49,451)				(49,451)
Balance at Sep. 30, 2022	100,428	$ 5	441,137	(391)	(340,323)
Balance (in Shares) at Sep. 30, 2022		4,685,698
Balance at Jun. 30, 2022	117,350	$ 5	440,189	(433)	(322,411)
Balance (in Shares) at Jun. 30, 2022		4,682,014
Issuance of common stock under employee stock purchase plan	54		54
Issuance of common stock under employee stock purchase plan, Shares		4,409
Cancellation of restricted stock		(725)
Equity-based compensation expense	894		894
Unrealized gain (loss) on securities	42			42
Net loss	(17,912)				(17,912)
Balance at Sep. 30, 2022	100,428	$ 5	441,137	(391)	(340,323)
Balance (in Shares) at Sep. 30, 2022		4,685,698
Balance at Dec. 31, 2022	82,610	$ 5	442,303	(161)	(357,019)	$ (2,518)
Balance (in Shares) at Dec. 31, 2022		4,728,874				(279,792)
Issuance of common stock under employee stock purchase plan	124		124
Issuance of common stock under employee stock purchase plan, Shares		34,489
Proceeds from issuance of common stock, net of issuance costs	1,249		1,249
Proceeds from issuance of common stock, net of issuance costs, Shares		115,966
Issuance of restricted stock, shares		10,814
Cancellation of restricted stock		(11,947)
Reverse Split: fractional share adjustment, Shares		(107)
Equity-based compensation expense	2,003		2,003
Unrealized gain (loss) on securities	166			166
Net loss	(42,748)				(42,748)
Balance at Sep. 30, 2023	43,404	$ 5	445,679	5	(399,767)	$ (2,518)
Balance (in Shares) at Sep. 30, 2023		4,878,089				(279,792)
Balance at Jun. 30, 2023	54,774	$ 5	444,974	2	(387,689)	$ (2,518)
Balance (in Shares) at Jun. 30, 2023		4,854,048				(279,792)
Issuance of common stock under employee stock purchase plan	65		65
Issuance of common stock under employee stock purchase plan, Shares		27,156
Cancellation of restricted stock		(3,008)
Reverse Split: fractional share adjustment, Shares		(107)
Equity-based compensation expense	640		640
Unrealized gain (loss) on securities	3			3
Net loss	(12,078)				(12,078)
Balance at Sep. 30, 2023	$ 43,404	$ 5	$ 445,679	$ 5	$ (399,767)	$ (2,518)
Balance (in Shares) at Sep. 30, 2023		4,878,089				(279,792)

Fair Value of Financial Instruments - Schedule of Assets measured at fair value and the gross unrealized holding gains and losses (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized Cost	$ 24,535	$ 15,861
Gross Unrealized Gain	1	0
Gross Unrealized Loss	0	0
Estimated Fair Value	24,536	15,861
Commercial Paper \| Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	2,472	44,375
Commercial Paper \| Cash and Cash Equivalents
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized Cost	8,977
Gross Unrealized Gain	1
Gross Unrealized Loss	0
Estimated Fair Value	8,978
Commercial Paper \| Cash and Cash Equivalents \| Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	8,978
U.S. government agency securities and treasuries \| Cash and Cash Equivalents
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized Cost	1,984
Gross Unrealized Gain	0
Gross Unrealized Loss	0
Estimated Fair Value	1,984
Money market funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized Cost	13,574	15,861
Gross Unrealized Gain	0	0
Gross Unrealized Loss	0	0
Estimated Fair Value	13,574	15,861
Money market funds \| Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	$ 13,574	$ 15,861

Equity based Compensation - Schedule of Equity-based Compensation Expenses (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Equity-based compensation expense	$ 640	$ 894	$ 2,003	$ 2,761
Research and Development Expense
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Equity-based compensation expense	223	390	739	1,143
General and Administrative Expense
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Equity-based compensation expense	$ 417	$ 504	$ 1,264	$ 1,618

Subsequent Events (Additional Information) (Details) - USD ($) $ / shares in Units, $ in Millions	Oct. 03, 2023	Dec. 31, 2023	Oct. 31, 2023	Sep. 30, 2023	Dec. 31, 2022
Subsequent Event [Line Items]
Common stock, Issued				4,878,089	4,728,874
Subsequent Event [Member]
Subsequent Event [Line Items]
Common stock, Issued	3,921,928
Pre-Funded Warrants To Purchase			3,472,435
Common stock and warrants purchase	7,394,363
Sale of stock, price per share	$ 2.84
Pre-funded warrant public offering price	2.839
Common stock at an exercise price	$ 3.408
Underwriting discounts and commissions and offering expenses payable			$ 19.6
Deferred revenue balance		$ 0.3
Pre fund warrant purchase description	A holder of pre-funded warrants may not exercise the warrant if the holder, together with its affiliates, would beneficially own more than 4.99% (or, at the election of the holder, 9.99%) of the number of shares of common stock outstanding immediately after giving effect to such exercise.
Subsequent Event [Member] \| Roche Collaboration and Option Agreement
Subsequent Event [Line Items]
Research and milestone payment			$ 2.5

Summary of Significant Accounting Policies

9 Months Ended

Sep. 30, 2023

Accounting Policies [Abstract]

Summary of Significant Accounting Policies

(2)

Summary of Significant Accounting Policies

The significant accounting policies described in the Company’s audited financial statements as of and for the year ended December 31, 2022, and the notes thereto, which are included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2022, filed with the Securities and Exchange Commission (SEC) on March 29, 2023 (the 2022 Annual Report), have had no material changes during the nine months ended September 30, 2023, other than the note below.

Reverse Stock Split

On September 27, 2023, the Company effected a one-for-fifteen reverse stock split of its issued and outstanding common stock, which also adjusted all outstanding warrants. Accordingly, all share and per share amounts for all periods presented in the accompanying condensed consolidated financial statements and notes thereto have been adjusted retroactively, where applicable, to reflect this stock split. All fractional shares resulting from the reverse stock split were paid in cash.

Basis of Presentation

The accompanying consolidated financial statements and the related disclosures as of September 30, 2023 and for the three and nine months ended September 30, 2023 and 2022 are unaudited and have been prepared in accordance with accounting principles generally accepted in the United States (GAAP) and the rules and regulations of the SEC for interim financial statements. Accordingly, they do not include all of the information and notes required by GAAP for complete financial statements. These interim consolidated financial statements should be read in conjunction with the Company’s 2022 and 2021 audited consolidated financial statements and notes included in the 2022 Annual Report. The consolidated balance sheet as of December 31, 2022 included herein was derived from the audited financial statements as of that date but does not include all disclosures including notes required by GAAP for complete financial statements. In the opinion of management, the unaudited interim consolidated financial statements reflect all adjustments, consisting of normal and recurring adjustments, necessary for the fair presentation of the Company’s financial position and results of operations for the three and nine months ended September 30, 2023 and 2022. The results of operations for the interim periods are not necessarily indicative of the results to be expected for the year ending December 31, 2023 or any other interim period or future year or period.

Principles of Consolidation

The accompanying consolidated financial statements include the accounts of Synlogic and its wholly owned subsidiaries. All intercompany accounts and transactions have been eliminated in consolidation.

Recently Issued Accounting Pronouncements

New accounting pronouncements are issued by the Financial Accounting Standards Board (FASB) from time to time, and rules are issued by the SEC that the Company has or will adopt as of a specified date. Unless otherwise noted, management does not believe that any recently issued accounting pronouncements issued by the FASB or guidance issued by the SEC had, or is expected to have, a material impact on the Company’s present or future financial statements.

Commitments and Contingencies

9 Months Ended

Sep. 30, 2023

Commitments and Contingencies Disclosure [Abstract]

Commitments and Contingencies

(12)

Commitments and Contingencies

In the ordinary course of business, the Company may be subject to legal proceedings, claims and litigation as the Company operates in an industry susceptible to patent legal claims. The Company accounts for estimated losses with respect to legal proceedings and claims when such losses are probable and estimable. Legal costs associated with these matters are expensed when incurred. The Company is not currently a party to any material legal proceedings.

The Company’s commitments described in the Company’s consolidated financial statements as of and for the year ended December 31, 2022 and the notes thereto included in the 2022 Annual Report have had no material changes during the nine months ended September 30, 2023.

Unaudited Consolidated Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Income Statement [Abstract]
Revenue	$ 393	$ 678	$ 602	$ 1,074
Operating expenses:
Research and development	9,616	14,610	33,831	38,405
General and administrative	3,400	4,402	11,291	12,785
Total operating expenses	13,016	19,012	45,122	51,190
Loss from operations	(12,623)	(18,334)	(44,520)	(50,116)
Other income (expense):
Interest and investment income	549	422	1,794	658
Interest expense	0	(1)	(1)	(3)
Other income (expense)	(1)	1	(9)	10
Total other income, net	548	422	1,784	665
Loss before income taxes	(12,075)	(17,912)	(42,736)	(49,451)
Income tax expense	(3)	0	(12)	0
Net loss	$ (12,078)	$ (17,912)	$ (42,748)	$ (49,451)
Net loss per share - basic	$ (2.57)	$ (3.73)	$ (9.17)	$ (10.29)
Net loss per share - diluted	$ (2.57)	$ (3.73)	$ (9.17)	$ (10.29)
Weighted-average common stock outstanding - basic	4,699,847	4,807,207	4,662,444	4,804,127
Weighted-average common stock outstanding - diluted	4,699,847	4,807,207	4,662,444	4,804,127
Comprehensive loss:
Net loss	$ (12,078)	$ (17,912)	$ (42,748)	$ (49,451)
Net unrealized (loss) gain on marketable securities	3	42	166	(346)
Comprehensive loss	$ (12,075)	$ (17,870)	$ (42,582)	$ (49,797)

Property and Equipment, Net - Schedule of Property and Equipment, Net (Detail) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 20,598	$ 20,463
Less accumulated depreciation	(14,649)	(13,140)
Property and equipment, net	5,949	7,323
Laboratory Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	9,350	9,313
Computer and Office Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	793	793
Furniture and Fixtures
Property Plant And Equipment [Line Items]
Property and equipment, gross	500	500
Leasehold Improvements
Property Plant And Equipment [Line Items]
Property and equipment, gross	9,820	9,820
Construction in Progress
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 135	$ 37

Equity based Compensation

9 Months Ended

Sep. 30, 2023

Share-Based Payment Arrangement [Abstract]

Equity based Compensation

(8)

Equity-based Compensation

On January 1, 2023, the number of shares of common stock available for issuance under the 2015 Equity Incentive Award Plan (the 2015 Plan) and the 2015 Employee Stock Purchase Plan (ESPP) was increased by 222,454 shares and 44,490 shares, respectively, due to the annual evergreen provision to increase shares available under the 2015 Plan and the ESPP. As of September 30, 2023, there were an aggregate of 175,874 shares available for future grant under the 2017 Stock Incentive Plan (the 2017 Plan) and the 2015 Plan, and 95,134 shares available for future grant under the ESPP.

The following table summarizes equity‑based compensation expense within the Company’s consolidated statements of operations and comprehensive loss for the three and nine months ended September 30, 2023 and 2022 (in thousands):


	Three Months Ended September 30,				Nine Months Ended September 30,
	2023		2022		2023		2022
Research and development	$	223	$	390	$	739	$	1,143
General and administrative		417		504		1,264		1,618
	$	640	$	894	$	2,003	$	2,761

The following table summarizes equity‑based compensation expense by type of award for the three and nine months ended September 30, 2023 and 2022 (in thousands):


	Three Months Ended September 30				Nine Months Ended September 30,
	2023		2022		2023		2022
Stock options	$	509	$	764	$	1,656	$	2,429
Restricted stock awards		93		111		280		277
ESPP		38		19		67		55
	$	640	$	894	$	2,003	$	2,761

During the nine months ended September 30, 2023, the Company granted 303,810 stock options with a weighted average exercise price of $9.31 per share. As of September 30, 2023, there was $3.9 million of unrecognized share-based compensation related to unvested stock option grants which is expected to be recognized over a weighted average period of 2.25 years. The total unrecognized share-based compensation cost will be adjusted for actual forfeitures as they occur.

During the nine months ended September 30, 2023, the Company granted 10,803 restricted stock awards with a weighted average grant date fair value per share of $9.30. As of September 30, 2023, there was approximately $0.8 million of unrecognized share-based compensation related to restricted stock awards granted, which is expected to be recognized over a weighted average period of 2.2 years. The total unrecognized share-based compensation cost will be adjusted for actual forfeitures as they occur.

For a full description of the Company’s equity plans, refer to Note 9, Equity-based Compensation and Equity Incentive Plans in the 2022 Annual Report.

Share Repurchase

9 Months Ended

Sep. 30, 2023

Share Repurchase [Abstract]

Share Repurchase

(11)

Share Repurchase

On November 25, 2022, the Company entered into a definitive share repurchase agreement with a stockholder, as part of a privately negotiated transaction, to repurchase 279,792 shares of common stock held by them for an aggregate purchase price of $2.5 million, or $9.00 per share. This repurchase was completed on November 28, 2022.

Repurchased shares are held as treasury stock at cost until they are retired or re-issued. There were no additional shares repurchased and no retirements or re-issuances of treasury stock during the nine months ended September 30, 2023.

Summary of Significant Accounting Policies (Additional Information) (Details)		3 Months Ended	9 Months Ended
	Sep. 27, 2023	Sep. 30, 2023	Sep. 30, 2023
Accounting Policies [Abstract]
Reverse Stock Split ,Decsription	the Company effected a reverse stock split of its shares of common stock, pursuant to which every fifteen (15) shares of the its issued and outstanding common stock was automatically converted into one (1) issued and outstanding share of common stock without any change in the par value of $0.001 per share.	The shares of common stock and the Ginkgo pre-funded warrants to purchase common stock were adjusted, as a result of the reverse stock split, during the three months ended September 30, 2023.	On September 27, 2023, the Company effected a one-for-fifteen reverse stock split of its issued and outstanding common stock, which also adjusted all outstanding warrants. Accordingly, all share and per share amounts for all periods presented in the accompanying condensed consolidated financial statements and notes thereto have been adjusted retroactively, where applicable, to reflect this stock split. All fractional shares resulting from the reverse stock split were paid in cash.

Accrued Expenses (Tables)

9 Months Ended

Sep. 30, 2023

Payables and Accruals [Abstract]

Schedule of Accrued Expenses

Accrued expenses consist of the following (in thousands):


	September 30,		December 31,
	2023		2022
Payroll related	$	2,356	$	3,401
Professional fees		838		152
Research and development		385		1,624
Other		100		113
Total accrued expenses	$	3,679	$	5,290

Net Loss per Share - Additional Information (Detail) - $ / shares		1 Months Ended	3 Months Ended	9 Months Ended
	Sep. 27, 2023	Jun. 30, 2019	Sep. 30, 2023	Sep. 30, 2023
Reverse Stock Split ,Decsription	the Company effected a reverse stock split of its shares of common stock, pursuant to which every fifteen (15) shares of the its issued and outstanding common stock was automatically converted into one (1) issued and outstanding share of common stock without any change in the par value of $0.001 per share.		The shares of common stock and the Ginkgo pre-funded warrants to purchase common stock were adjusted, as a result of the reverse stock split, during the three months ended September 30, 2023.	On September 27, 2023, the Company effected a one-for-fifteen reverse stock split of its issued and outstanding common stock, which also adjusted all outstanding warrants. Accordingly, all share and per share amounts for all periods presented in the accompanying condensed consolidated financial statements and notes thereto have been adjusted retroactively, where applicable, to reflect this stock split. All fractional shares resulting from the reverse stock split were paid in cash.
Common Stock $0.001 Par Value
Proceeds from issuance of common stock, net of issuance costs, Shares		422,718		115,966
Pre-Funded Warrants
Warrants to purchase shares of common stock		169,874
Warrants exercise price per share		$ 135
Warrants exercise price per share paid at closing of offering		$ 134.85

Stockholders Equity - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands		1 Months Ended		3 Months Ended	9 Months Ended
	Sep. 27, 2023	Jul. 31, 2021	Jun. 30, 2019	Sep. 30, 2023	Sep. 30, 2023	Dec. 31, 2022
Class Of Stock [Line Items]
Common stock, par value	$ 0.001			$ 0.001	$ 0.001	$ 0.001
Reverse Stock Split Approval Date	Sep. 21, 2023
Reverse Stock Split ,Decsription	the Company effected a reverse stock split of its shares of common stock, pursuant to which every fifteen (15) shares of the its issued and outstanding common stock was automatically converted into one (1) issued and outstanding share of common stock without any change in the par value of $0.001 per share.			The shares of common stock and the Ginkgo pre-funded warrants to purchase common stock were adjusted, as a result of the reverse stock split, during the three months ended September 30, 2023.	On September 27, 2023, the Company effected a one-for-fifteen reverse stock split of its issued and outstanding common stock, which also adjusted all outstanding warrants. Accordingly, all share and per share amounts for all periods presented in the accompanying condensed consolidated financial statements and notes thereto have been adjusted retroactively, where applicable, to reflect this stock split. All fractional shares resulting from the reverse stock split were paid in cash.
Common Stock
Class Of Stock [Line Items]
Sale of common stock, shares			422,718		115,966
Pre-Funded Warrants
Class Of Stock [Line Items]
Warrants to purchase shares of common stock			169,874
Warrants exercise price per share			$ 135
Warrants exercise price per share paid at closing of offering			134.85
Ginkgo Bioworks, Inc.
Class Of Stock [Line Items]
Sale of stock, price per share			$ 135
Proceeds from issuance of common stock and pre-funded warrants			$ 79,900
Ginkgo Bioworks, Inc. \| Common Stock
Class Of Stock [Line Items]
Sale of common stock, shares			422,718
Ginkgo Bioworks, Inc. \| Pre-Funded Warrants
Class Of Stock [Line Items]
Warrants exercise price per share			$ 135
Warrants exercise price per share paid at closing of offering			$ 134.85
Warrants exercised				0	0
Ginkgo Bioworks, Inc. \| Pre-Funded Warrants \| Maximum Member
Class Of Stock [Line Items]
Warrants to purchase shares of common stock			169,874
Jefferies, LLC \| ATM
Class Of Stock [Line Items]
Sale of common stock, shares					115,966
Proceeds from issuance of common stock in connection with at-the-market offering, net of issuance costs		$ 50,000			$ 1,250

Stockholders' Equity (Tables)

9 Months Ended

Sep. 30, 2023

Equity [Abstract]

Schedule of Shares of Common Stock Reserved for Future Issuance


	September 30, 2023
Common stock issuable under Ginkgo pre-funded warrants		169,874
Options exercisable to purchase common stock		292,805
Employee Stock Purchase Plan		—
Total		462,679

Nature of Business - Additional Information (Detail) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Cash, cash equivalents, and short-term marketable securities	$ 33,400
Restricted cash	1,097	$ 1,097
Accumulated deficit	$ 399,767	$ 357,019

- Definition

Amount of accumulated undistributed earnings (deficit).

+ References + Details

Available-for-Sale Securities - Summary of Available-for-Sale Securities Held (Detail) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	$ 8,875	$ 61,929
Gross unrealized gains	4	8
Gross unrealized losses	0	(169)
Fair Value	8,879	61,768
Commercial Paper
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	2,472	44,437
Gross unrealized gains	0	8
Gross unrealized losses	0	(70)
Fair Value	2,472	44,375
U.S. government agency securities and treasuries
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	6,403	17,492
Gross unrealized gains	4
Gross unrealized losses	0	(99)
Fair Value	$ 6,407	$ 17,393

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (aa)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (aaa)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-3

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-3

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-3

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-3

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-3

+ Details

Equity based Compensation (Tables)

9 Months Ended

Sep. 30, 2023

Share-Based Payment Arrangement [Abstract]

Schedule of Equity-based Compensation Expenses


	Three Months Ended September 30,				Nine Months Ended September 30,
	2023		2022		2023		2022
Research and development	$	223	$	390	$	739	$	1,143
General and administrative		417		504		1,264		1,618
	$	640	$	894	$	2,003	$	2,761

Schedule of Equity-based Compensation Expenses by Award Type

The following table summarizes equity‑based compensation expense by type of award for the three and nine months ended September 30, 2023 and 2022 (in thousands):


	Three Months Ended September 30				Nine Months Ended September 30,
	2023		2022		2023		2022
Stock options	$	509	$	764	$	1,656	$	2,429
Restricted stock awards		93		111		280		277
ESPP		38		19		67		55
	$	640	$	894	$	2,003	$	2,761

Fair Value of Financial Instruments (Tables)

9 Months Ended

Sep. 30, 2023

Fair Value Disclosures [Abstract]

Schedule of Company's Classified Assets Measured at Fair Value on Recurring Basis

At September 30, 2023 and December 31, 2022, the Company has classified assets measured at fair value on a recurring basis as follows (in thousands):


	Fair Value Measurements at Reporting Date Using
	September 30,		Quoted Prices in Active Markets for Identical Assets		Significant Other Observable Inputs		Significant Unobservable Inputs
Description	2023		(Level 1)		(Level 2)		(Level 3)
Money market funds (included in cash and cash equivalents)	$	13,574	$	13,574	$	—	$	—
Commercial paper (included in cash and cash equivalents)		8,978		—		8,978		—
Commercial paper		2,472				2,472		—
U.S. treasuries (included in cash and cash equivalents)		1,984		1,984
U.S. government agency securities and treasuries		6,407		1,973		4,434		—
Total	$	33,415	$	17,531	$	15,884	$	—

	Fair Value Measurements at Reporting Date Using
	December 31,		Quoted Prices in Active Markets for Identical Assets		Significant Other Observable Inputs		Significant Unobservable Inputs
Description	2022		(Level 1)		(Level 2)		(Level 3)
Money market funds (included in cash and cash equivalents)	$	15,861	$	15,861	$	—	$	—
Commercial paper		44,375		—		44,375		—
U.S. treasuries		17,393		17,393		—		—
Total	$	77,629	$	33,254	$	44,375	$	—

Schedule of Fair Value Assets and Liabilities Measured Gross Unrealized Gains and Losses

The following tables summarize the estimated fair value of the assets presented within cash and cash equivalents measured at fair value and the gross unrealized holding gains and losses (in thousands):


September 30, 2023	Amortized Cost		Gross unrealized gains		Gross unrealized losses		Fair Value
Money market funds (included in cash and cash equivalents)	$	13,574	$	—	$	—	$	13,574
Commercial paper (included in cash and cash equivalents)		8,977		1		—	$	8,978
U.S. treasuries (included in cash and cash equivalents)		1,984		—		—	$	1,984
Total	$	24,535	$	1	$	—	$	24,536

December 31, 2022	Amortized Cost		Gross unrealized gains		Gross unrealized losses		Fair Value
Money market funds (included in cash and cash equivalents)	$	15,861	$	—	$	—	$	15,861
Total	$	15,861	$	—	$	—	$	15,861

Property and Equipment, Net (Tables)

9 Months Ended

Sep. 30, 2023

Property, Plant and Equipment [Abstract]

Schedule of Property and Equipment, Net

Property and equipment, net consists of the following (in thousands):


	September 30,			December 31,
	2023			2022
Laboratory equipment	$	9,350		$	9,313
Computer and office equipment		793			793
Furniture and fixtures		500			500
Leasehold improvements		9,820			9,820
Construction in progress		135			37
		20,598			20,463
Less accumulated depreciation		(14,649	)		(13,140	)
Property and equipment, net	$	5,949		$	7,323

Unaudited Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Cash flows from operating activities:
Net loss	$ (42,748)	$ (49,451)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation	1,555	1,907
Gain on disposal of property and equipment	(11)	0
Equity-based compensation expense	2,003	2,761
Accretion/amortization of investment securities	(512)	(364)
Change in carrying amount of operating lease right of use asset	2,469	2,347
Changes in operating assets and liabilities:
Accounts receivable	0	(1,500)
Prepaid expenses and other current assets	(2,212)	419
Prepaid research and development, net of current portion	(286)	1,780
Accounts payable and accrued expenses	(2,688)	107
Deferred revenue	(618)	440
Operating lease liabilities	(3,030)	(2,932)
Other assets	(8)	(9)
Net cash used in operating activities	(46,086)	(44,495)
Cash flows from investing activities:
Purchases of marketable securities	(8,831)	(66,191)
Proceeds from maturity of marketable securities	62,398	110,366
Purchases of property and equipment	(186)	(685)
Proceeds from the sale of property and equipment	16	0
Net cash provided by investing activities	53,397	43,490
Cash flows from financing activities:
Payments on finance lease obligations	(9)	(9)
Proceeds from employee stock purchases and exercise of stock options	124	198
Net cash provided by financing activities	1,364	189
Net increase (decrease) in cash, cash equivalents and restricted cash	8,675	(816)
Cash, cash equivalents and restricted cash at beginning of period	16,958	17,535
Cash, cash equivalents and restricted cash at end of period	25,633	16,719
Supplemental disclosure of non-cash investing activities:
Assets acquired under operating lease obligation	940	2,698
Property and equipment purchases included in accounts payable and accrued expenses	0	35
Supplemental disclosure of non-cash financing activities:
Cash paid for income taxes	12	0
Cash paid for interest	1	2
Issuance costs included in accounts payable and accrued expenses	295	0
At-the-market Offering
Cash flows from financing activities:
Proceeds from issuance of common stock in connection with at-the-market offering, net of issuance costs	$ 1,249	$ 0

Unaudited Consolidated Balance Sheets (Parenthetical) - $ / shares	Sep. 30, 2023	Dec. 31, 2022
Statement of Financial Position [Abstract]
Common stock, par value	$ 0.001	$ 0.001
Common stock, authorized	250,000,000	250,000,000
Common stock, Issued	4,878,089	4,728,874
Common stock, outstanding	4,598,297	4,449,082
Treasury stock, shares	279,792	279,792

Related-Party Transactions	9 Months Ended
Related-Party Transactions	Sep. 30, 2023
Related Party Transactions [Abstract]
Related-Party Transactions	Related-Party Transactions In June 2019, the Company expanded its collaboration and entered into an agreement with Ginkgo for the research and development of engineered microbial therapeutic products. As of September 30, 2023, Ginkgo owned 422,718 shares of the Company’s outstanding common stock. See Note 10, Ginkgo Collaboration, in the audited financial statements included in the 2022 Annual Report. Under the agreement the Company made a prepayment to Ginkgo of $30.0 million for its foundry services that will be provided to the Company over an initial term of five years. At September 30, 2023, the Company had remaining balances of $0.8 million and $5.2 million of current and non-current prepaid research and development costs related to this transaction, respectively. The Company utilized $0.8 million and $2.3 million of the prepaid research and development expenses for the three and nine months ended September 30, 2023, respectively

- Definition

The entire disclosure for related party transactions. Examples of related party transactions include transactions between (a) a parent company and its subsidiary; (b) subsidiaries of a common parent; (c) and entity and its principal owners; and (d) affiliates.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480990/946-20-50-2

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+ Details

Collaboration Agreements

9 Months Ended

Sep. 30, 2023

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Collaboration Agreements

(9)

Collaboration Agreements

Roche Collaboration

In June 2021, the Company entered into a Pilot Collaboration and Option Agreement (the Roche Collaboration and Option Agreement) with F. Hoffmann-La Roche Ltd (Roche Basel) and Hoffmann-La Roche Inc. (Roche US, and together with Roche Basel, Roche). Under the terms of the Roche Collaboration and Option Agreement, the Company and Roche will seek to collaborate to research and pre-clinically develop Synthetic Biotics for addressing an undisclosed novel target for the treatment of inflammatory bowel disease.

During the nine months ended September 30, 2023 and 2022, the Company recognized $0.6 million and $1.1 million, respectively, as collaboration revenue associated with the Roche Collaboration and Option Agreement. Deferred revenue from the collaboration amounted to $0.3 million as of September 30, 2023, all of which is included in current liabilities.

For a full description of the Roche Collaboration and Option Agreement, refer to Note 10, Collaboration Agreements in the 2022 Annual Report.

Ginkgo Collaboration

In 2017, the Company established a technology collaboration with Ginkgo. In June 2019, the Company expanded its collaboration and entered into an agreement with Ginkgo for the research and development of engineered microbial therapeutic products (See Note 7). Under the 2019 expanded agreement, the Company made a prepayment to Ginkgo of $30.0 million for its foundry services that will be provided to the Company over an initial term of five years, which may be extended for an additional three (3) years, subject to the satisfaction of specified conditions. The prepayment of foundry services is recorded in Prepaid expenses and other current assets and Prepaid research and development, net of current portion on the September 30, 2023 consolidated balance sheet. At September 30, 2023, the Company had remaining balances of $0.8 million and $5.2 million of current and non-current prepaid research and development costs related to this transaction, respectively. Upon the expiration of such initial term and, if applicable, an additional term, any portion of the prepayment that has not been used to purchase services from Ginkgo will be retained by Ginkgo.

Unaudited Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Current assets:
Cash and cash equivalents	$ 24,536	$ 15,861
Short-term marketable securities	8,879	61,768
Prepaid expenses and other current assets	4,365	2,153
Total current assets	37,780	79,782
Property and equipment, net	5,949	7,323
Right of use asset - operating lease	12,827	14,356
Restricted cash	1,097	1,097
Prepaid research and development, net of current portion	8,586	8,300
Other assets	15	7
Total assets	66,254	110,865
Current liabilities:
Accounts payable	708	1,785
Accrued expenses	3,679	5,290
Deferred revenue	264	882
Lease liability - operating lease	4,485	4,152
Finance lease obligations	8	13
Total current liabilities	9,144	12,122
Long-term liabilities:
Lease liability - operating lease, net of current portion	13,706	16,129
Finance lease obligations, net of current portion	0	4
Total long-term liabilities	13,706	16,133
Commitments and contingencies (Note 12)
Stockholders' equity
Common stock, $0.001 par value 250,000,000 shares authorized as of September 30, 2023 and December 31, 2022,4,878,089 shares issued and 4,598,297 shares outstanding as of September 30, 2023 and 4,728,874 shares issued and 4,449,082 shares outstanding as of December 31, 2022	5	5
Additional paid-in capital	445,679	442,303
Accumulated other comprehensive income (loss)	5	(161)
Accumulated deficit	(399,767)	(357,019)
Treasury stock, at cost (279,792 shares at September 30, 2023 and December 31, 2022)	(2,518)	(2,518)
Total stockholders' equity	43,404	82,610
Total liabilities and stockholders' equity	$ 66,254	$ 110,865

Commitments and Contingencies - Additional Information (Detail) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Gain Contingencies [Line Items]
Right of use asset - operating lease	$ 12,827	$ 14,356

Accrued Expenses

9 Months Ended

Sep. 30, 2023

Payables and Accruals [Abstract]

Accrued Expenses

(6)

Accrued Expenses

Accrued expenses consist of the following (in thousands):


	September 30,		December 31,
	2023		2022
Payroll related	$	2,356	$	3,401
Professional fees		838		152
Research and development		385		1,624
Other		100		113
Total accrued expenses	$	3,679	$	5,290

Fair Value of Financial Instruments

9 Months Ended

Sep. 30, 2023

Fair Value Disclosures [Abstract]

Fair Value of Financial Instruments

(3)

Fair Value of Financial Instruments

The tables below present information about the Company’s assets that are measured at fair value on a recurring basis and indicate the fair value hierarchy of the valuation techniques the Company utilized to determine such fair value, as described under Note 2, Summary of Significant Accounting Policies, in the audited financial statements included in the 2022 Annual Report.

The Company’s investment portfolio includes many fixed income securities that do not always trade on a daily basis. As a result, the pricing services used by the Company applied other available information as applicable through processes such as benchmark yields, benchmarking of like securities, sector groupings and matrix pricing to prepare evaluations. In addition, model processes were used to assess interest rate impact and develop prepayment scenarios. These models take into consideration relevant credit information, perceived market movements, sector news and economic events. The inputs into these models may include benchmark yields, reported trades, broker-dealer quotes, issuer spreads and other relevant data.

At September 30, 2023 and December 31, 2022, the Company has classified assets measured at fair value on a recurring basis as follows (in thousands):


	Fair Value Measurements at Reporting Date Using
	September 30,		Quoted Prices in Active Markets for Identical Assets		Significant Other Observable Inputs		Significant Unobservable Inputs
Description	2023		(Level 1)		(Level 2)		(Level 3)
Money market funds (included in cash and cash equivalents)	$	13,574	$	13,574	$	—	$	—
Commercial paper (included in cash and cash equivalents)		8,978		—		8,978		—
Commercial paper		2,472				2,472		—
U.S. treasuries (included in cash and cash equivalents)		1,984		1,984
U.S. government agency securities and treasuries		6,407		1,973		4,434		—
Total	$	33,415	$	17,531	$	15,884	$	—

	Fair Value Measurements at Reporting Date Using
	December 31,		Quoted Prices in Active Markets for Identical Assets		Significant Other Observable Inputs		Significant Unobservable Inputs
Description	2022		(Level 1)		(Level 2)		(Level 3)
Money market funds (included in cash and cash equivalents)	$	15,861	$	15,861	$	—	$	—
Commercial paper		44,375		—		44,375		—
U.S. treasuries		17,393		17,393		—		—
Total	$	77,629	$	33,254	$	44,375	$	—

Cash equivalents, prepaid expenses and other current assets, accounts payable and accrued expenses at September 30, 2023 and December 31, 2022 are carried at amounts that approximate fair value due to their short-term maturities. Finance lease obligations at September 30, 2023 and December 31, 2022 approximate fair value as they bear interest at a rate approximating a market interest rate.


September 30, 2023	Amortized Cost		Gross unrealized gains		Gross unrealized losses		Fair Value
Money market funds (included in cash and cash equivalents)	$	13,574	$	—	$	—	$	13,574
Commercial paper (included in cash and cash equivalents)		8,977		1		—	$	8,978
U.S. treasuries (included in cash and cash equivalents)		1,984		—		—	$	1,984
Total	$	24,535	$	1	$	—	$	24,536

December 31, 2022	Amortized Cost		Gross unrealized gains		Gross unrealized losses		Fair Value
Money market funds (included in cash and cash equivalents)	$	15,861	$	—	$	—	$	15,861
Total	$	15,861	$	—	$	—	$	15,861

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Summary of Significant Accounting Policies (Policies)	9 Months Ended
Summary of Significant Accounting Policies (Policies)	Sep. 30, 2023
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying consolidated financial statements and the related disclosures as of September 30, 2023 and for the three and nine months ended September 30, 2023 and 2022 are unaudited and have been prepared in accordance with accounting principles generally accepted in the United States (GAAP) and the rules and regulations of the SEC for interim financial statements. Accordingly, they do not include all of the information and notes required by GAAP for complete financial statements. These interim consolidated financial statements should be read in conjunction with the Company’s 2022 and 2021 audited consolidated financial statements and notes included in the 2022 Annual Report. The consolidated balance sheet as of December 31, 2022 included herein was derived from the audited financial statements as of that date but does not include all disclosures including notes required by GAAP for complete financial statements. In the opinion of management, the unaudited interim consolidated financial statements reflect all adjustments, consisting of normal and recurring adjustments, necessary for the fair presentation of the Company’s financial position and results of operations for the three and nine months ended September 30, 2023 and 2022. The results of operations for the interim periods are not necessarily indicative of the results to be expected for the year ending December 31, 2023 or any other interim period or future year or period.
Principles of Consolidation	Principles of Consolidation The accompanying consolidated financial statements include the accounts of Synlogic and its wholly owned subsidiaries. All intercompany accounts and transactions have been eliminated in consolidation.
Recently Issued Accounting Pronouncements	Recently Issued Accounting Pronouncements New accounting pronouncements are issued by the Financial Accounting Standards Board (FASB) from time to time, and rules are issued by the SEC that the Company has or will adopt as of a specified date. Unless otherwise noted, management does not believe that any recently issued accounting pronouncements issued by the FASB or guidance issued by the SEC had, or is expected to have, a material impact on the Company’s present or future financial statements.

Net Loss per Share - Schedule of Potentially Common Shares Excluded from Calculation of Net Loss Per share (Detail) - shares	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Unvested Restricted Common Stock Awards
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially Common Shares Excluded from Calculation of Net Loss Per share	41,798	43,951
Stock Options
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially Common Shares Excluded from Calculation of Net Loss Per share	653,927	491,151
Potential Shares Issuable Under ESPP
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially Common Shares Excluded from Calculation of Net Loss Per share	0	0

Related-Party Transactions - Additional Information (Detail) - USD ($) $ in Millions	1 Months Ended	3 Months Ended	9 Months Ended
	Jun. 30, 2019	Sep. 30, 2023	Sep. 30, 2023	Dec. 31, 2022
Related Party Transaction [Line Items]
Common stock, outstanding		4,598,297	4,598,297	4,449,082
Ginkgo Bioworks, Inc.
Related Party Transaction [Line Items]
Common stock, outstanding		422,718	422,718
Prepayment to related party for collaboration agreement	$ 30.0
Related party transaction collaboration agreement, initial term	5 years
Current Pre-Paid Research and Development		$ 0.8	$ 0.8
Non Current Pre-Paid Research and Development		5.2	5.2
Prepaid research and development expenses		$ 0.8	$ 2.3

Nature of Business

9 Months Ended

Sep. 30, 2023

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Nature of Business

(1)

Nature of Business

Organization

Synlogic, Inc., together with its wholly owned and consolidated subsidiaries (Synlogic or the Company), is a late-stage biopharmaceutical company advancing novel, orally-administered, non-systemically absorbed therapeutics for serious diseases based on the Company's Synthetic Biotic product platform. Synthetic Biotics are generated from Synlogic’s proprietary platform, leveraging a reproducible, modular approach to the generation of novel drug candidates that perform or deliver critical therapeutic functions. Synthetic Biotics are designed to metabolize a toxic substance, compensate for missing or damaged metabolic pathways or deliver combinations of therapeutic factors. Synlogic’s goal is to discover, develop and ultimately commercialize Synthetic Biotics. Since incorporation, the Company has devoted substantially all of its efforts to the research and development of its product candidates.

Risks and Uncertainties

At September 30, 2023, the Company had approximately $33.4 million in cash and cash equivalents, $1.1 million of restricted cash and an accumulated deficit of approximately $399.8 million. Since its inception through September 30, 2023, the Company has primarily financed its operations through the issuance of preferred stock, units and warrants, the sale of its common stock, and collaborations, including with Roche. In the absence of positive cash flows from operations, the Company is highly dependent on its ability to find additional sources of funding in the form of debt or equity financing. Inclusive of the net cash proceeds received in October 2023 from the sale of the Company's common stock, as further described in Note 14, Subsequent Events, management believes that the Company has sufficient cash and other sources of liquidity, including cash equivalents, to fund its operations through at least twelve months from the date of issuance of these financial statements.

As a clinical-stage company, the Company is subject to a number of risks common to other life science companies, including, but not limited to, raising additional capital, development by its competitors of new technological innovations, risk of failure in preclinical and clinical studies, safety and efficacy of its product candidates in clinical trials, the risk of relying on external parties such as contract research organizations (CROs) and contract manufacturing organizations (CMOs), the regulatory approval process, market acceptance of the Company’s products once approved, lack of marketing and sales history, dependence on key personnel and protection of proprietary technology. The Company’s therapeutic programs are currently pre-commercial, spanning discovery through development and will require significant additional research and development efforts, including extensive preclinical and clinical testing and regulatory approval, prior to commercialization of any product candidates. These efforts require significant amounts of additional capital, adequate personnel, infrastructure, and extensive compliance-reporting capabilities. There can be no assurance that the Company’s research and development will be successfully completed, that adequate protection for the Company’s intellectual property will be obtained, that any products developed will obtain necessary regulatory approval or that any approved products will be commercially viable. Even if the Company’s product development efforts are successful, it is uncertain when, if ever, the Company will generate revenue from product sales. The Company may never achieve profitability, and unless and until it does, it will continue to need to raise additional capital or obtain financing from other sources, such as strategic collaborations or alliances.

COVID-19

While the Company is not aware of a material impact from the continuation of the COVID-19 pandemic through September 30, 2023, the full extent to which the COVID-19 pandemic will directly or indirectly impact the Company’s business, results of operations, and financial condition, including expenses and manufacturing, clinical trials, and research and development costs, depends on future developments that are uncertain at this time.

Subsequent Events

9 Months Ended

Sep. 30, 2023

Subsequent Events [Abstract]

Subsequent Events

On October 3, 2023, the Company issued and sold, through an underwritten public offering:

•

3,921,928 shares of its common stock at a price of $2.84 per share less underwriting discounts and commissions;

•

pre-funded warrants to purchase up to 3,472,435 shares of its common stock at a price of $2.839 immediately following the consummation of the offering, and;

•

accompanying common stock warrants to purchase up to 7,394,363 shares of its common stock at a price of $3.408 per share exercisable immediately after issuance and expires five years from the date of issuance.

Each share of its common stock and each pre-funded warrant was sold together with a common warrant to purchase one share of its common stock. A holder of pre-funded warrants may not exercise the warrant if the holder, together with its affiliates, would beneficially own more than 4.99% (or, at the election of the holder, 9.99%) of the number of shares of common stock outstanding immediately after giving effect to such exercise. The net proceeds to the Company from the sale of common stock and pre-funded warrants through the offering, after deducting the underwriting discounts and commissions and offering expenses payable by the Company, were approximately $19.6 million.

In October 2023, the Company achieved its third pre-specified research milestone under the terms of the Roche Collaboration and Option Agreement and earned a third milestone payment of $2.5 million, payable to the Company within 45 days. The Company will recognize the remainder of the deferred revenue balance, $0.3 million, in the fourth quarter of 2023

Stockholders Equity - Schedule of Shares of Common Stock Reserved for Future Issuance (Detail)	Sep. 30, 2023 shares
Class Of Stock [Line Items]
Total Shares of Common Stock Reserved for Future Issuance	462,679
Common Stock Issuable Under Pre-Funded Warrants
Class Of Stock [Line Items]
Total Shares of Common Stock Reserved for Future Issuance	169,874
Options Exercisable to Purchase Common Stock
Class Of Stock [Line Items]
Total Shares of Common Stock Reserved for Future Issuance	292,805
Employee Stock Purchase Plan
Class Of Stock [Line Items]
Total Shares of Common Stock Reserved for Future Issuance	0

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
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+ Details

Accrued Expenses - Schedule of Accrued Expenses (Detail) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Payables and Accruals [Abstract]
Payroll related	$ 2,356	$ 3,401
Professional fees	838	152
Research and development	385	1,624
Other	100	113
Total accrued expenses	$ 3,679	$ 5,290

Available-for-Sale Securities - Additional Information (Detail) $ in Millions	Sep. 30, 2023 Investment	Dec. 31, 2022 USD ($) Investment
Investments, Debt and Equity Securities [Abstract]
Number of investments in unrealized loss position, more than twelve months \| Investment	0	0
Aggregate fair value of securities in unrealized loss position \| $		$ 36.6

Share Repurchase (Additional Information) (Details) $ / shares in Units, $ in Millions	Nov. 25, 2022 USD ($) $ / shares shares
Share Repurchase [Abstract]
Repurchase of common stock \| shares	279,792
Aggregate Purchase \| $	$ 2.5
Aggregate Purchase Per Share \| $ / shares	$ 9

Fair Value of Financial Instruments - Schedule of Company's Classified Assets Measured at Fair Value on Recurring Basis (Detail) - USD ($)	Sep. 30, 2023	Dec. 31, 2022
Fair Value Asset Measured On Recurring Basis [Line Items]
Estimated Fair Value	$ 24,536,000	$ 15,861,000
Money market funds
Fair Value Asset Measured On Recurring Basis [Line Items]
Estimated Fair Value	13,574,000	15,861,000
Cash and Cash Equivalents \| Commercial Paper
Fair Value Asset Measured On Recurring Basis [Line Items]
Estimated Fair Value	8,978,000
Cash and Cash Equivalents \| U.S. government agency securities and treasuries
Fair Value Asset Measured On Recurring Basis [Line Items]
Estimated Fair Value	1,984,000
Recurring
Fair Value Asset Measured On Recurring Basis [Line Items]
Total assets	33,415	77,629,000
Recurring \| Money market funds
Fair Value Asset Measured On Recurring Basis [Line Items]
Estimated Fair Value	13,574,000	15,861,000
Recurring \| Commercial Paper
Fair Value Asset Measured On Recurring Basis [Line Items]
Estimated Fair Value	2,472,000	44,375,000
Recurring \| U.S. government agency securities and treasuries
Fair Value Asset Measured On Recurring Basis [Line Items]
Short-term investments	6,407,000	17,393,000
Recurring \| Cash and Cash Equivalents \| Commercial Paper
Fair Value Asset Measured On Recurring Basis [Line Items]
Estimated Fair Value	8,978,000
Recurring \| Cash and Cash Equivalents \| U.S. government agency securities and treasuries
Fair Value Asset Measured On Recurring Basis [Line Items]
Short-term investments	1,984,000
Recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value Asset Measured On Recurring Basis [Line Items]
Total assets	17,531	33,254,000
Recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| Money market funds
Fair Value Asset Measured On Recurring Basis [Line Items]
Estimated Fair Value	13,574,000	15,861,000
Recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| Commercial Paper
Fair Value Asset Measured On Recurring Basis [Line Items]
Estimated Fair Value		0
Recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| U.S. government agency securities and treasuries
Fair Value Asset Measured On Recurring Basis [Line Items]
Short-term investments	1,973,000	17,393,000
Recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| Cash and Cash Equivalents \| Commercial Paper
Fair Value Asset Measured On Recurring Basis [Line Items]
Estimated Fair Value	0
Recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| Cash and Cash Equivalents \| U.S. government agency securities and treasuries
Fair Value Asset Measured On Recurring Basis [Line Items]
Short-term investments	1,984,000
Recurring \| Significant Other Observable Inputs (Level 2)
Fair Value Asset Measured On Recurring Basis [Line Items]
Total assets	15,884	44,375,000
Recurring \| Significant Other Observable Inputs (Level 2) \| Money market funds
Fair Value Asset Measured On Recurring Basis [Line Items]
Estimated Fair Value	0	0
Recurring \| Significant Other Observable Inputs (Level 2) \| Commercial Paper
Fair Value Asset Measured On Recurring Basis [Line Items]
Estimated Fair Value	2,472,000	44,375,000
Recurring \| Significant Other Observable Inputs (Level 2) \| U.S. government agency securities and treasuries
Fair Value Asset Measured On Recurring Basis [Line Items]
Short-term investments	4,434,000	0
Recurring \| Significant Other Observable Inputs (Level 2) \| Cash and Cash Equivalents \| Commercial Paper
Fair Value Asset Measured On Recurring Basis [Line Items]
Estimated Fair Value	8,978,000
Recurring \| Significant Unobservable Inputs (Level 3)
Fair Value Asset Measured On Recurring Basis [Line Items]
Total assets	0	0
Recurring \| Significant Unobservable Inputs (Level 3) \| Money market funds
Fair Value Asset Measured On Recurring Basis [Line Items]
Estimated Fair Value	0	0
Recurring \| Significant Unobservable Inputs (Level 3) \| Commercial Paper
Fair Value Asset Measured On Recurring Basis [Line Items]
Estimated Fair Value	0	0
Recurring \| Significant Unobservable Inputs (Level 3) \| U.S. government agency securities and treasuries
Fair Value Asset Measured On Recurring Basis [Line Items]
Short-term investments	0	$ 0
Recurring \| Significant Unobservable Inputs (Level 3) \| Cash and Cash Equivalents \| Commercial Paper
Fair Value Asset Measured On Recurring Basis [Line Items]
Estimated Fair Value	$ 0