Sign in

SYBX on OTC

SYNLOGIC, INC.

In its 2026 annual report the company says: “We are a biopharmaceutical company that previously advanced novel therapeutics to transform the care of serious diseases. We focused on rare metabolic disorders, with our lead program, labafenogene marselecobac (SYNB1934), studied in Synpheny-3, a global, pivotal Phase 3 study for patients with phenylketonuria (PKU), and SYNB1353, a potential treatment for homocystinuria (HCU).”5 It is headquartered in Winchester, Massachusetts.1 Its shares trade on OTC under the symbol SYBX.1

$1.08 up 0.06 (5.88%)Price as of Oct 15, 2026 at 17:33 UTC

Last updated Oct 21, 2026.

Overview

Compare with GENELUX Corp, Azitra, Inc. or Aspire-Lakewood Holdings, Inc., or pick any stock.

  • TickerSYBX on OTC1
  • IndustryPharmaceutical Preparations1
  • HeadquartersWinchester, Massachusetts1
  • Incorporated inDE3
  • Business addressPo Box 30, Winchester, Ma 018903
  • Filer categoryNon-accelerated filer, Smaller reporting company3

See how the biggest companies compare on our leaderboards

We are a biopharmaceutical company that previously advanced novel therapeutics to transform the care of serious diseases. We focused on rare metabolic disorders, with our lead program, labafenogene marselecobac (SYNB1934), studied in Synpheny-3, a global, pivotal Phase 3 study for patients with phenylketonuria (PKU), and SYNB1353, a potential treatment for homocystinuria (HCU). Both PKU and HCU are caused by inborn errors of metabolism, and present significant need for innovation due to limitations of both efficacy and safety in the currently available medical treatment options. In February 2024, we made the decision to discontinue Synpheny-3, our pivotal study of our lead product candidate, labafenogene marselecobac (SYNB1934), as a potential treatment for PKU. The decision to end Synpheny-3 is based on results of an internal review in advance of an upcoming independent Data Monitoring …5 From its latest annual report

Financials

From the company’s reports to the SEC. Every number links to the filing it came from.

Key numbers, fiscal 2025

-100.0%Revenue growth, 20256
-8.5%Return on equity6
-$4.4MFree cash flow6

Financial statements

Revenue78910116$0 in 2025
0$1.0M$2.0M$3.0M$4.0M2019: $2.2M$2.2M20192020: $545.0K$545.0K2020−75%2021: $1.8M$1.8M2021+222%2022: $1.2M$1.2M2022−33%2023: $3.4M$3.4M2023+186%2024: $8.0K$8.0K2024−100%2025: $0$02025
Operating income78910116-$4.0M in 2025−93% since 2019
-$80.0M-$60.0M-$40.0M-$20.0M02019: -$54.4M-$54.4M20192020: -$60.5M-$60.5M2020+11%2021: -$60.8M-$60.8M2021+0%2022: -$67.4M-$67.4M2022+11%2023: -$55.2M-$55.2M2023−18%2024: -$41.0M-$41.0M2024−26%2025: -$4.0M-$4.0M2025−90%
Net income78910116-$1.0M in 2025−98% since 2019
-$80.0M-$60.0M-$40.0M-$20.0M02019: -$51.4M-$51.4M20192020: -$59.2M-$59.2M2020+15%2021: -$60.6M-$60.6M2021+2%2022: -$66.1M-$66.1M2022+9%2023: -$61.3M-$61.3M2023−7%2024: -$23.4M-$23.4M2024−62%2025: -$1.0M-$1.0M2025−96%

Every line of the income statement as filed: the last 2 fiscal years, latest first.6

Period ending2025-12-312024-12-31
Revenue$0$8.0K
Research and development$43.0K$9.2M
General and administrative$3.5M$6.6M
Restructuring and other charges$476.0K$25.2M
Total operating expenses$4.0M$41.0M
Loss from operations-$4.0M-$41.0M
Interest and investment income$695.0K$1.4M
Change in fair value of purchase warrant liability$2.3M$16.2M
Other expense$0-$2.0K
Total other income (expense), net$3.0M$17.6M
Loss before income taxes-$1.0M-$23.4M
Income tax expense$0-$5.0K
Net loss-$1.0M-$23.4M
Net loss per share - basic and diluted-$0.08-$1.92
Net loss per share - basic and diluted-$0.08-$1.92
Weighted-average common stock outstanding - basic and diluted12.3M shares12.2M shares
Weighted-average common stock outstanding - basic and diluted12.3M shares12.2M shares
Net unrealized (loss) gain on marketable securities$0-$6.0K
Comprehensive loss-$1.0M-$23.4M

Compare SYNLOGIC, INC. with another company

Corporate structure

SYNLOGIC, INC. sits at the top of its group. 3 entities, 1 country on record. Switch between the flow chart and the network, and select any entity to see its details.

Major holders of SYNLOGIC, INC.

  • Funicular Funds, LP Filed SCHEDULE 13D/A on SYNLOGIC, INC., latest Jul 29, 2026 (3 filings since Feb 16, 2024)
  • New Enterprise Associates 14, L.P. Filed SCHEDULE 13D/A on SYNLOGIC, INC., latest Jul 29, 2026 (3 filings since Oct 13, 2023)
  • Baselake Partners, LP Filed SCHEDULE 13G on SYNLOGIC, INC., latest Jan 23, 2026
  • Radoff Bradley Louis Filed SCHEDULE 13G/A on SYNLOGIC, INC., latest Nov 13, 2025 (2 filings since Apr 18, 2024)
  • John A. Kryzanowski Filed SCHEDULE 13G/A on SYNLOGIC, INC., latest Feb 25, 2025 (4 filings since Jan 20, 2023)
  • ARMISTICE CAPITAL, LLC Filed SC 13G/A on SYNLOGIC, INC., latest Nov 14, 2024 (2 filings since Feb 14, 2024)
  • FMR LLC Filed SC 13G/A on SYNLOGIC, INC., latest Feb 9, 2024 (4 filings since Feb 9, 2022)
  • ORBIMED ADVISORS LLC Filed SC 13D/A on SYNLOGIC, INC., latest Oct 4, 2023
  • RA CAPITAL MANAGEMENT, L.P. Filed SC 13G/A on SYNLOGIC, INC., latest Feb 14, 2023 (2 filings since Oct 1, 2021)
  • SYNLOGIC, INC. Winchester, Massachusetts
    • Synlogic Operating Company, Inc. Subsidiary · Delaware, United States
    • Synlogic Securities Corporation Subsidiary · Massachusetts, United States

Built from subsidiaries listed in Exhibit 21 of annual reports filed with the SEC; major holders from Schedules 13D and 13G. Each entity in the chart links to its source.

What it owns

What SYNLOGIC, INC. reports owning in its annual reports to the SEC: buildings, land and equipment, real estate and locations, investments, intangible assets and inventory, at the end of its latest fiscal year and a year before.

Property and equipment

ItemLatestA year beforeChange
Leasehold improvements$9.5M11 Dec 31, 2024
Property and equipment, net$011 Dec 31, 2024$5.6M11 Dec 31, 2023−100.0%
Operating-lease assets (leased space)$011 Dec 31, 2024$12.1M11 Dec 31, 2023−100.0%

Investments

ItemLatestA year beforeChange
Cash and cash equivalents$14.7M6 Dec 31, 2025$18.9M6 Dec 31, 2024−22.2%
Marketable securities, current$011 Dec 31, 2024$23.8M11 Dec 31, 2023−100.0%

Properties, in its own words

Until June 26, 2024, our corporate headquarters and operations were located in Cambridge, Massachusetts.

As described further under Note 7: Restructuring and Other Charges, in connection with the corporate restructuring, on June 26, 2024 (the “Termination Date”), the Company entered into a Lease Termination Agreement (the “Termination Agreement”) for its corporate headquarters at 301 Binney Street in Cambridge, Massachusetts, with the landlord which, effective immediately, terminated the lease.

The rest of Item 2

The official address of our corporate headquarters and operations is P.O. Box 30, Winchester, Massachusetts 01890. We believe that our existing office space is adequate to meet current requirements, and that suitable additional or substitute space will be available as needed to accommodate our operations.

Item 2 of the 10-K filed Mar 12, 2026.5

Leadership

Who has led SYNLOGIC, INC., and when. Pick a name to see everywhere that person has worked.

Chief executive

  1. Paul Lammers2015–2016
  2. Aoife Brennan2018–2023

President

  1. Paul Lammers2015–2016
  2. Aoife Brennan2018–2023

Chief financial officer

  1. Alan Fuhrman2015–2016
  2. Michael Vangsted Jensen2022–2023

Chief operating officer

  1. Andrew Gengos2018
  2. Antoine Awad2020–2024
20202025
Board members and other officers (34)

Subsidiaries and ownership

Subsidiaries (Exhibit 21)

The subsidiaries the company lists in Exhibit 21 of its annual report, as filed.

Former names

  • Mirna Therapeutics, Inc.Aug 23, 2011 to Aug 25, 20173

Timeline

  1. Jul 29, 20268-K Entered a material agreement; Change to shareholders' rights; Change in control50
  2. Jan 29, 20268-K Listing notice or transfer; Other events51
  3. Jan 20, 20268-K Listing notice or transfer52
  4. Dec 16, 20258-K Executive or director change; Shareholder vote53
  5. Nov 26, 20258-K Listing notice or transfer54
  6. Feb 21, 20258-K Executive or director change55
  7. Jan 14, 20258-K Executive or director change56
  8. Dec 23, 20248-K Executive or director change57
  9. Dec 5, 20248-K Shareholder vote58
  10. Nov 12, 20248-K Results of operations59
  11. Aug 8, 20248-K Results of operations60
  12. May 14, 20248-K Results of operations61
  13. Jun 6, 2018New chief executive Aoife Brennan becomes CEO14
  14. Sep 30, 2015New chief executive Paul Lammers becomes CEO15

Calendar

When it reported results

  1. Nov 12, 2024Reported quarterly or annual results59
  2. Aug 8, 2024Reported quarterly or annual results60
  3. May 14, 2024Reported quarterly or annual results61
  4. Mar 19, 2024Reported quarterly or annual results62
  5. Feb 12, 2024Reported quarterly or annual results63
  6. Nov 9, 2023Reported quarterly or annual results64
  7. Aug 10, 2023Reported quarterly or annual results65
  8. May 11, 2023Reported quarterly or annual results66

Upcoming dates from Nasdaq's calendar; past results from the company's 8-K filings (Item 2.02). The full markets calendar

Filings

182 filings to the SEC since October 2021: 8 annual reports, 15 quarterly reports, 47 major events, 49 insider forms, 22 large holders, 41 other. The latest 20:

  1. Aug 14, 20264 EDGAR
  2. Aug 11, 202610-Q EDGAR
  3. Jul 29, 2026425 EDGAR
  4. Jul 29, 20268-K EDGAR
  5. Jul 29, 2026SCHEDULE 13D/A EDGAR
  6. Jul 29, 2026SCHEDULE 13D/A EDGAR
  7. May 18, 202625-NSE EDGAR
  8. May 14, 202610-Q EDGAR
  9. Apr 30, 202610-K/A EDGAR
  10. Apr 6, 2026SCHEDULE 13D/A EDGAR
  11. Mar 12, 202610-K EDGAR
  12. Jan 29, 20268-K/A EDGAR
  13. Jan 23, 2026SCHEDULE 13G EDGAR
  14. Jan 20, 20268-K EDGAR
  15. Dec 16, 20258-K EDGAR
  16. Nov 26, 20258-K EDGAR
  17. Nov 13, 202510-Q EDGAR
  18. Nov 13, 2025SCHEDULE 13G/A EDGAR
  19. Nov 12, 2025ARS EDGAR
  20. Nov 12, 2025DEF 14A EDGAR

The 182 filings since October 2021 can be filtered by form type and year here when JavaScript is on.

Every filing from the last five years, summarized. The full record is on SEC EDGAR.

Insider trades

12 open-market trades by officers, directors and large owners since October 2021: 1 buys and 11 sales. Grants, option exercises and gifts are left out.

DateWhoTradeSharesPriceValueFiling
Oct 29, 2025Dooley Mary BethSee Remarks belowSale157$1.81$284Form 4
Apr 2, 2025Dooley Mary BethSee Remarks belowSale144$1.20$173Form 4
Feb 3, 2025Dooley Mary BethSee Remarks belowSale2,107$1.33$2.8KForm 4
Oct 29, 2024Dooley Mary BethSee Remarks belowSale79$1.40$111Form 4
Apr 2, 2024Dooley Mary BethSee Remarks belowSale188$1.73$325Form 4
Apr 2, 2024Awad AntoineChief Operating OfficerSale372$1.73$644Form 4
Apr 3, 2023Awad AntoineChief Operating OfficerSale6,438$0.58$3.7KForm 4
Apr 3, 2023Brennan AoifePresident and CEOSale19,042$0.58$11.0KForm 4
Apr 3, 2023JENSEN MICHAEL VANGSTEDChief Financial OfficerSale2,553$0.58$1.5KForm 4
May 24, 2022JENSEN MICHAEL VANGSTEDChief Financial OfficerBuy9,500$1.12$10.6KForm 4
Apr 4, 2022Brennan AoifePresident and CEOSale8,894$2.45$21.8KForm 4
Apr 4, 2022Awad AntoineChief Operating OfficerSale2,650$2.45$6.5KForm 4

From Forms 4 filed with the SEC.

Major holders

Investors who own more than 5% of the shares must tell the SEC: a 13D if they may seek to influence the company, a 13G if they hold passively.

Executive pay

What the company paid its top executives, from the summary compensation table in its proxy statement. Total pay includes salary, bonus, stock and option awards and other pay, as the company valued them.

YearExecutiveAgeSalaryTotal pay
2024Antoine Awad$437.7K$1.3M76
2024Aoife M. BrennanMB, BCh, BAO, MMSc$119.2K$1.1M76
2024Mary Beth Dooley44$325.0K$486.5K76
2023Former President and Chief Executive Officer$613.0K$1.2M76
2023Former PrincipalExecutive Officer$422.9K$701.5K76
2023Principal Executive Officer and Principal Financial Officer$303.1K$433.5K76

Held by these funds

The largest holders among investment managers' 13F reports for the quarter ending Jun 30, 2026. Change is in shares since the quarter before.

FundSharesValueShare of the fundChange
DRW Securities, LLC23,763$16.7K0.0%No change

13F reports cover disclosed long positions in U.S. stocks only.

SEC filer profile

How SYNLOGIC, INC. is registered with the Securities and Exchange Commission, from its EDGAR record and the cover page of its latest annual report.

  • Name on EDGARSYNLOGIC, INC.1
  • CIK0001527599
  • Employer ID (EIN)26-18248045
  • Filer statusNon-accelerated filer not an emerging growth company; a smaller reporting company; a shell company5
  • Incorporated inDelaware5
  • Fiscal year endsDecember 311
  • Industry code (SIC)2834 Pharmaceutical Preparations1
  • SEC reviewing officeOffice of Life Sciences, Division of Corporation Finance1
  • Business addressPo Box 30, Winchester, MA 018901
  • Phone617-659-28021
  • Shares outstanding12,248,950 as of Aug 4, 202613
  • Public float$4.4M as of Jun 30, 20255
  • AuditorKPMG LLP, Boston, Massachusetts, U.S. PCAOB ID 185; no auditor attestation of internal control over financial reporting5
  • On EDGAR sinceAug 23, 20111
  • Filings625 in all: 4 (194), 8-K (130), 3 (55), 10-Q (33), SC 13G/A (22), SC 13G (16), S-8 (15), CORRESP (14)1
    All 45 form types

    SC 13D/A (13), UPLOAD (12), 10-K (11), 424B5 (10), DEF 14A (10), EFFECT (8), S-1/A (7), CT ORDER (6), DEFA14A (6), 425 (5), S-3 (5), SC 13D (5), D (4), DRS/A (4), 10-K/A (3), ARS (3), S-3/A (3), SCHEDULE 13D/A (3), 144 (2), 424B3 (2), 424B4 (2), 8-A12B (2), 8-K/A (2), DRSLTR (2), PRE 14A (2), S-1 (2), SCHEDULE 13G/A (2), 25-NSE (1), 3/A (1), 5 (1), CERTNAS (1), DRS (1), FWP (1), S-1MEF (1), S-4 (1), S-4/A (1), SCHEDULE 13G (1)

  • Latest filingsAnnual report (10-K) Mar 12, 2026
    Quarterly report (10-Q) Aug 11, 2026
    Proxy statement (DEF 14A) Nov 12, 2025
    Latest 8-K (8-K) Jul 29, 2026

Risk factors and legal proceedings

The risks SYNLOGIC, INC. names in Item 1A of its 10-K filed Mar 12, 2026: 32 risks under these headings, as written.5

  • Risks Related to Our Securities
  • Our securities have been delisted from Nasdaq, which has limited and may continue to limit investors’ ability to make transactions in our securities.
  • We are a non-operating shell company.
  • An active trading market for our securities may never develop and investors may find it difficult to buy and sell our shares, which would further adversely affect the liquidity and price of our securities.
  • Our securityholders may face restrictions on the resale of our securities due to state “blue sky” laws.
  • As a result of our delisting from Nasdaq, we are more likely to require holders of our warrants who exercise their warrants to do so on a cashless basis and such holders may receive fewer shares of common stock upon exercise than they would have received had they been able to pay the exercise price of their warrants in cash.
  • We may be further delisted from the OTC Markets and may face additional adverse consequences.
  • Risks Related to Our Evaluation of Strategic Alternatives
  • Our business to date has been significantly dependent on the success of SYNB1934, and we have decided to discontinue further development of SYNB1934 and devote significant time and resources to identifying and evaluating strategic alternatives, which may not be successful.
  • If we do not successfully consummate a strategic transaction, our board of directors may decide to pursue a dissolution and liquidation of our company. In such an event, the amount of cash available for distribution to our stockholders will depend heavily on the timing of such liquidation as well as the amount of cash that will need to be reserved for commitments and contingent liabilities.
  • Risks Related to Our Financial Condition, Capital Requirements and Operating Results
  • Our stock price is volatile, and our stockholders may not be able to resell shares of our common stock at or above the price they paid.
The other 23 risks
  • Our short operating history may make it difficult for stockholders to evaluate the success of our business to date and to assess our future viability.
  • Our internal computer systems, or those of our collaborators or other contractors or consultants, may fail or suffer cybersecurity incidents, which could result in a material disruption of our product development programs.
  • Risks Related to Our Intellectual Property
  • We may not be successful in obtaining or maintaining necessary rights to Synthetic Biotics, product candidates and processes for our development pipeline through acquisitions and in-licenses.
  • We may not have sufficient patent term protections to effectively protect our business.
  • Changes in U.S. and foreign patent law could diminish the value of patents in general, thereby impairing our ability to protect our products, and recent patent reform legislation could increase the uncertainties and costs surrounding the prosecution of our patent applications and the enforcement or defense of our issued patents.
  • Obtaining And Maintaining Our Patent Protection Depends on Compliance with Various Procedural, Document Submission, Fee Payment and Other Requirements Imposed by Governmental Patent Agencies, And Our Patent Protection Could be Reduced or Eliminated for Non-Compliance with These Requirements.
  • If we are unable to maintain effective proprietary rights for our product candidates or any future product candidates, we may not be able to compete effectively in our proposed markets.
  • Third-party claims of intellectual property infringement may prevent or delay our development and commercialization efforts.
  • We depend, in part, on our licensors to file, prosecute, maintain, defend and enforce patents and patent applications that are material to our business.
  • If we fail to comply with obligations in the agreements under which we license intellectual property and other rights from third parties or otherwise experience disruptions to our business relationships with our licensors, we could lose license rights that are important to our business.
  • We may be involved in lawsuits to protect or enforce our patents or the patents of our licensors, which could be expensive, time consuming, and unsuccessful.
  • We may be subject to claims challenging the inventorship of our patents and other intellectual property.
  • We may be subject to claims that our employees, consultants, collaborators, advisors, independent contractors or other third parties have wrongfully used or disclosed confidential information of third parties or that our employees have wrongfully used or disclosed alleged trade secrets of their former employers.
  • We may not be able to protect our intellectual property rights throughout the world.
  • Some of our intellectual property may be subject to federal regulations such as “march-in” rights, certain reporting requirements and a preference for U.S.-based companies if it is determined that our intellectual property has been discovered through government-funded programs. Compliance with such regulations may limit our exclusive rights, and limit our ability to contract with non-U.S. manufacturers.
  • If our trademarks and trade names are not adequately protected, we may not be able to build name recognition in our markets of interest and our business may be adversely affected.
  • General Risk Factors
  • Our principal stockholders own a significant percentage of our stock and are able to exert significant control over matters subject to stockholder approval.
  • Future sales of our common stock or securities convertible or exchangeable for our common stock may depress our stock price.
  • Our quarterly operating results may fluctuate significantly or may fall below the expectations of investors or securities analysts, each of which may cause our stock price to fluctuate or decline.
  • Provisions of our charter documents or Delaware law could delay or prevent an acquisition of us, even if the acquisition would be beneficial to our stockholders and could make it more difficult for you to change management.
  • If securities or industry analysts do not publish research, or publish inaccurate or unfavorable research, about our business, our stock price and trading volume could decline.
  • Changes in, or interpretations of, accounting rules and regulations could result in unfavorable accounting charges or require us to change our compensation policies.
  • We will continue to incur costs as a result of being a public company, and our management will continue to devote substantial time to compliance initiatives and corporate governance practices.

Legal proceedings

From time to time, we are subject to various legal proceedings, claims and administrative proceedings that arise in the ordinary course of our business activities. Although the results of the litigation and claims cannot be predicated with certainty, as of the date of this report, we do not believe we are party to any claim, proceeding or litigation the outcome of which, if determined adversely to us, would individually or in the aggregate be reasonably expected to have a material adverse effect on our business. Regardless of the outcome, litigation can have an adverse impact on us because of defense and settlement costs, diversion of management resources and other factors.

The opening of Item 3, Legal Proceedings.5

Sources

The numbers on this page point here. Each one links to the record it came from.

  1. 1
  2. 2
    Yahoo FinanceSYBX quote
  3. 3
  4. 4
  5. 5
  6. 6
  7. 7
  8. 8
  9. 9
  10. 10
  11. 11
  12. 12
  13. 13
  14. 14
  15. 15
  16. 16
  17. 17
  18. 18
  19. 19
  20. 20
  21. 21
  22. 22
  23. 23
  24. 24
  25. 25
  26. 26
  27. 27
  28. 28
  29. 29
  30. 30
  31. 31
  32. 32
  33. 33
  34. 34
  35. 35
  36. 36
  37. 37
  38. 38
  39. 39
  40. 40
  41. 41
  42. 42
  43. 43
  44. 44
  45. 45
  46. 46
  47. 47
  48. 48
  49. 49
  50. 50
  51. 51
  52. 52
  53. 53
  54. 54
  55. 55
  56. 56
  57. 57
  58. 58
  59. 59
  60. 60
  61. 61
  62. 62
  63. 63
  64. 64
  65. 65
  66. 66
  67. 67
  68. 68
  69. 69
  70. 70
  71. 71
  72. 72
  73. 73
  74. 74
  75. 75
  76. 76