8-K
false 0001527599 0001527599 2022-12-15 2022-12-15

 

 

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

 

 

FORM 8-K

 

 

CURRENT REPORT

Pursuant to Section 13 or 15(d)

of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): December 15, 2022

 

 

SYNLOGIC, INC.

(Exact name of Registrant as Specified in Its Charter)

 

 

 

Delaware   001-37566   26-1824804

(State or Other Jurisdiction

of Incorporation)

 

(Commission

File Number)

 

(IRS Employer

Identification No.)

 

301 Binney St.

Suite 402

 
Cambridge, Massachusetts   02142
(Address of Principal Executive Offices)   (Zip Code)

Registrant’s Telephone Number, Including Area Code: (617) 401-9975

Not applicable

(Former Name or Former Address, if Changed Since Last Report)

 

 

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

 

Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

 

Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

 

Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

 

Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

 

Title of each class

 

Trading

Symbol(s)

 

Name of each exchange

on which registered

Common Stock, par value $0.001 per share   SYBX   The NASDAQ Global Market

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (17 CFR § 230.405) or Rule 12b-2 of the Securities Exchange Act of 1934 (17 CFR § 240.12b-2).

Emerging growth company  

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.  ☐

 

 

 


Item 8.01

Other Events.

On December 15, 2022, Synlogic, Inc. (the “Company”) issued a press release announcing that SYNB8802 has demonstrated proof of concept through clinically significant lowering of urinary oxalate in a Phase 1b study in patients with a history of gastric bypass surgery. A copy of the press release is attached hereto as Exhibit 99.1 and is incorporated by reference herein. The Company also provided slides to accompany its press release, a copy of which is furnished as Exhibit 99.2 to this Current Report on Form 8-K and is incorporated by reference herein.

 

Item 9.01.

Financial Statements and Exhibits.

(d) Exhibits

 

Exhibit

No.

   Description
99.1    Press Release dated December 15, 2022.
99.2    Slide Presentation dated December 15, 2022.
104    Cover Page Interactive Data File (embedded within the Inline XBRL document).


SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

 

Date: December 15, 2022   Synlogic, Inc.
    By:  

/s/ Michael Jensen

    Name:   Michael Jensen
    Title:   Chief Financial Officer
EX-99.1

Exhibit 99.1

 

LOGO

Synlogic Announces Achievement of Proof of Concept for SYNB8802 in Enteric Hyperoxaluria Based on Urinary Oxalate Lowering in Phase 1b Study

Results include -38% reduction in urinary oxalate compared to placebo in Roux-en-Y gastric bypass patients

Favorable safety and tolerability, with frequency and severity of adverse events similar across placebo and active arms

Synlogic to host webcast today at 8:30 am. ET with Dr. Kyle Wood, Associate Professor, Urology,University of Alabama at Birmingham

Cambridge, Mass. December 15, 2022 – Synlogic, Inc. (Nasdaq: SYBX), a clinical-stage biotechnology company developing medicines for metabolic and immunological diseases through its proprietary approach to synthetic biology, today announced that SYNB8802 has demonstrated proof of concept through clinically significant lowering of urinary oxalate in a Phase 1b study in patients with a history of gastric bypass surgery.

Top-line Findings:

 

   

In the Phase 1b SYNB8802-CP-002 study, SYNB8802 demonstrated a dose-related reduction in urinary oxalate.

 

   

The -38% urinary oxalate reduction observed at the 3x1011 live cell dose three times a day exceeds the level of urinary oxalate reduction (-20%) that has been associated with reduced risk of kidney stones in analyses based on observational data.1

 

   

SYNB8802 was generally well tolerated. There were no serious adverse events (SAEs). All GI-related adverse events (AEs) were mild, and their frequency and severity were similar in the active and placebo group.

“Given the profound need for a medical treatment for enteric hyperoxaluria, we are delighted to demonstrate meaningful reductions in urinary oxalate in the Roux-en-Y gastric bypass patient population,” said Aoife Brennan, M.B. Ch.B., Synlogic President and Chief Executive Officer. “In addition, this important milestone represents the third positive clinical data readout this year in three different diseases, following our positive Phase 2 results for SYNB1934 for phenylketonuria and positive Phase 1 results for SYNB1353 for homocystinuria.”


LOGO

 

“A subset of enteric patients have repeated kidney stones and life-altering disease that is particularly challenging to manage,” said Kyle Wood, MD, Associate Professor of Urology at the University of Alabama at Birmingham. “A therapeutic approach that lowers urinary oxalate in patients with underlying GI malabsorption is badly needed. The innovative mechanism of SYNB8802 and the strength of the data generated to date support the potential for SYNB8802 to be a highly meaningful first-in-category biotherapeutic.”

The SYNB8802-CP-002 Study

This Phase 1b study was a double-blind, randomized, placebo-controlled, inpatient study evaluating the safety and tolerability of SYNB8802 in subjects with a history of Roux-en-Y gastric bypass surgery. The primary endpoint was safety and tolerability. After a three-day diet and placebo run in, patients were randomized to either placebo or SYNB8802 for a 12-day dosing period. The dosing period included a dose escalation plan with the first six days at the lower dose of 1 × 1011 live cells, followed by six days at the 3 × 1011 live cell dose. Each six-day treatment period included a stepwise increase in dose frequency. To enable a controlled assessment of SYNB8802’s effects on oxalate, patients consumed a controlled diet for the duration of the inpatient stay. Urine was also collected for a 24-hour sample for each patient, each day.

The study enrolled 11 patients; 7 received SYNB8802 and 4 received placebo. SYNB8802 was well tolerated, with no SAEs. The most common AEs were GI-related, mild, and transient. The GI-related AEs occurred at a similar frequency in active and placebo groups. One patient in the placebo group discontinued during dosing due to the need for antibiotics.

Dosing with SYNB8802 was associated with a dose-dependent reduction in urinary oxalate. In a pharmacometric analysis that takes into account all patients’ data, dose level and dose frequency, there was a -28% (-37.2, -18.2) change from baseline in urinary oxalate vs. placebo at the 1x1011 TID dose, and a -38% (-46.4, -28.7) change from baseline in urinary oxalate vs. placebo at the 3x1011 TID dose.

In addition to the completed SYNB8802-CP-002 study, SYNB8802 is also being evaluated in an ongoing, outpatient study (SYNB8802-CP-001). Full results from both studies will be presented at a future medical meeting.

Conference Call & Webcast

Synlogic will host a conference call and live webcast at 8:30 a.m. ET today, December 15, 2022. Joining will be Dr. Kyle Wood, a specialist in kidney stone-related disease in his role as Associate Professor, Urology, University of Alabama at Birmingham. To access the webcast, please register here. To access the call by phone please dial (646) 307-1963 or for a toll-free option in the U.S. and Canada dial (800) 715-9871. The event ID is: 4065357. You can also access this information on the “Events Calendar” section of the Investors & Media webpage. For those unable to participate in the conference call or webcast, a replay will be available for 30 days on the Synlogic website here.


LOGO

 

About Enteric Hyperoxaluria and SYNB8802

Enteric hyperoxaluria (EH) is a metabolic disease and well-recognized cause of recurrent kidney stones, typically caused by a chronic underlying GI disorder associated with malabsorption, which predisposes patients to excessive absorption of oxalate. Elevated oxalate in the circulation leads to oxalate crystal formation in the kidney, causing excruciating pain and progressive renal damage. There is no FDA-approved treatment for enteric hyperoxaluria. SYNB8802 is a novel, orally administered, non-systemically absorbed drug candidate being developed for the treatment of enteric hyperoxaluria. SYNB8802 was designed using precision genetic engineering of the well-characterized probiotic E. coli Nissle to metabolize oxalate in GI tract, preventing its absorption and resultant crystal formation, lowering levels of urinary oxalate.

References

1 D’Costa et al. Nephrol Dial Transplant (2020) 1–8.

About Synlogic

Synlogic is a clinical-stage biotechnology company developing medicines through its proprietary approach to synthetic biology. Synlogic’s pipeline includes its lead program in phenylketonuria (PKU), which has demonstrated proof of concept with plans to start a pivotal, Phase 3 study in the first half of 2023, and additional novel drug candidates designed to treat homocystinuria (HCU), enteric hyperoxaluria and gout. The rapid advancement of these potential biotherapeutics, called Synthetic Biotics, has been enabled by Synlogic’s reproducible, target-specific drug design. Synlogic uses programmable, precision genetic engineering of well-characterized probiotics to exert localized activity for therapeutic benefit, with a focus on metabolic and immunological diseases. In addition to its clinical programs, Synlogic has a research collaboration with Roche on the discovery of a novel Synthetic Biotic for the treatment of inflammatory bowel disease or IBD. Synlogic has also developed two drug candidates through a research collaboration with Ginkgo Bioworks: SYNB1353, designed to consume methionine for the potential treatment of HCU, and SYNB2081, designed to lower uric acid for the potential treatment of gout. For additional information visit www.synlogictx.com.


LOGO

 

Forward-Looking Statements

This press release contains “forward-looking statements” that involve substantial risks and uncertainties for purposes of the safe harbor provided by the Private Securities Litigation Reform Act of 1995. All statements, other than statements of historical facts, included in this press release regarding strategy, future operations, clinical development plans, future financial position, future revenue, projected expenses, prospects, plans and objectives of management are forward-looking statements. In addition, when or if used in this press release, the words “may,” “could,” “should,” “anticipate,” “believe,” “look forward,” “estimate,” “expect,” “intend,” “on track,” “plan,” “predict” and similar expressions and their variants, as they relate to Synlogic, may identify forward-looking statements. Examples of forward-looking statements, include, but are not limited to, statements regarding the potential of Synlogic’s approach to Synthetic Biotics to develop therapeutics to address a wide range of diseases including: inborn errors of metabolism and inflammatory and immune disorders; our expectations about sufficiency of our existing cash balance; the future clinical development of Synthetic Biotics; the approach Synlogic is taking to discover and develop novel therapeutics using synthetic biology; and the expected timing of Synlogic’s clinical trials of SYNB1618, SYNB1934, SYNB1353, SYNB8802 and SYNB2081 and availability of clinical trial data. Actual results could differ materially from those contained in any forward-looking statements as a result of various factors, including: the uncertainties inherent in the clinical and preclinical development process; the ability of Synlogic to protect its intellectual property rights; and legislative, regulatory, political and economic developments, as well as those risks identified under the heading “Risk Factors” in Synlogic’s filings with the U.S. Securities and Exchange Commission. The forward-looking statements contained in this press release reflect Synlogic’s current views with respect to future events. Synlogic anticipates that subsequent events and developments will cause its views to change. However, while Synlogic may elect to update these forward-looking statements in the future, Synlogic specifically disclaims any obligation to do so. These forward-looking statements should not be relied upon as representing Synlogic’s view as of any date subsequent to the date hereof.

 

MEDIA CONTACT:    INVESTOR CONTACT:

Bill Berry

Berry & Company Public Relations

Phone: 212-253-8881

Email: bberry@berrypr.com

  

Andrew Funderburk

Kendall Investor Relations

Phone: 617-401-9152

Email: afunderburk@kendallir.com

EX-99.2

Exhibit 99.2 Transforming Medicine Through Synthetic Biology Proof of Concept for SYNB8802 for Enteric Hyperoxaluria Top-Line Results from Phase 1b Study December 15, 2022 © © 2 20 02 22 2 SY SYN NLO LOG GIIC C.. P PR RO OO OF F O OF F C CO ON NC CE EP PT T F FO OR R SY SYN NB B8 88 80 02 2 IIN N E EH H.. A ALL R LL RIIG GH HT TS R S RE ESE SER RV VE ED D..


Forward Looking Statements This presentation contains forward-looking statements that involve substantial risks and uncertainties for purposes of the safe harbor provided by the Private Securities Litigation Reform Act of 1995. All statements, other than statements of historical facts, included in this presentation regarding strategy, future operations, clinical development plans, future financial position, future revenue, projected expenses, prospects, plans and objectives of management are forward-looking statements. In addition, when or if used in this presentation, the words may, could, should, anticipate, believe, “look forward,” estimate, expect, intend, on track,” plan, predict and similar expressions and their variants, as they relate to Synlogic, may identify forward-looking statements. Examples of forward-looking statements, include, but are not limited to, statements regarding the potential of Synlogic's approach to Synthetic Biotics to develop therapeutics to address a wide range of diseases including: inborn errors of metabolism and inflammatory and immune disorders; our expectations about sufficiency of our existing cash balance; the future clinical development of Synthetic Biotics; the approach Synlogic is taking to discover and develop novel therapeutics using synthetic biology; and the expected timing of Synlogic's clinical trials of SYNB1618, SYNB1934, SYNB1353, SYNB8802 and SYNB2081 and availability of clinical trial data. Actual results could differ materially from those contained in any forward-looking statements as a result of various factors, including: the uncertainties inherent in the clinical and preclinical development process; the ability of Synlogic to protect its intellectual property rights; and legislative, regulatory, political and economic developments, as well as those risks identified under the heading Risk Factors in Synlogic's filings with the U.S. Securities and Exchange Commission. The forward-looking statements contained in this presentation reflect Synlogic's current views with respect to future events. Synlogic anticipates that subsequent events and developments will cause its views to change. However, while Synlogic may elect to update these forward-looking statements in the future, Synlogic specifically disclaims any obligation to do so. These forward-looking statements should not be relied upon as representing Synlogic's view as of any date subsequent to the date hereof. © 2022 SYNLOGIC. PROOF OF CONCEPT FOR SYNB8802 IN EH. ALL RIGHTS RESERVED.


Speakers Aoife Brennan, MB ChB Kyle Wood, MD Caroline Kurtz, PhD Dave Hava, PhD President & CEO Associate Professor, Urology, Chief Development Officer Chief Scientific Officer University of Alabama at Birmingham © 2022 SYNLOGIC. PROOF OF CONCEPT FOR SYNB8802 IN EH. ALL RIGHTS RESERVED.


Opening Remarks Dr. Aoife Brennan President & CEO © © 2 20 02 22 2 SY SYN NLO LOG GIIC C.. P PR RO OO OF F O OF F C CO ON NC CE EP PT T F FO OR R SY SYN NB B8 88 80 02 2 IIN N E EH H.. A ALL R LL RIIG GH HT TS R S RE ESE SER RV VE ED D..


SYNB8802: Enteric POC Achieved with Potential for Hyperoxaluria & Urinary Oxalate First Approved the Burden of Lowering from Treatment for Recurrent Phase 1b Study Enteric Kidney Stones Hyperoxaluria © 2022 SYNLOGIC. PROOF OF CONCEPT FOR SYNB8802 IN EH. ALL RIGHTS RESERVED.


Enteric Hyperoxaluria & Recurrent Kidney Stones: An Overview Dr. Kyle Wood Associate Professor, Urology University of Alabama at Birmingham © 2020 SYNLOGIC. QU ARTE R LY R ES U LT S.A LLRIG H TS RESERVED .| 3 © 2022 SYNLOGIC. PROOF OF CONCEPT FOR SYNB8802 IN EH. ALL RIGHTS RESERVED. © 201 9 SY NLO G IC. ALL RI G HTS RESERVE D. | 3


`` `` Enteric Hyperoxaluria (EH) & Recurrent Kidney Stones • Oxalate crystals damage kidneys, impair renal Excruciating function Pain • Can lead to CKD, ESRD, Dietary Oxalate*: nephrocalcinosis, plant-derived; in systemic oxalosis excess, absorbed Circulating from GI tract into oxalate results in circulation crystal formation and chronic, recurrent kidney stones © 2022 SYNLOGIC. PROOF OF CONCEPT FOR SYNB8802 IN EH. ALL RIGHTS RESERVED. GI = gastrointestinal, CKD = chronic kidney disease, ESRD = end stage renal disease. 1. D’Costa, et al. Nephrol Dial Transpla nt (2020)


Urinary Oxalate Levels: Recognized Predictor of Recurrent Stones Higher urinary oxalate (UOx) levels predict stone events in EH patients, with ~20% decrease in UOx associated with ~25% reduction in annual 1 stone event risk 1. D’Costa, et al. Nephrol Dial Transplant (2020) © 2022 SYNLOGIC. PROOF OF CONCEPT FOR SYNB8802 IN EH. ALL RIGHTS RESERVED.


Urinary Oxalate Levels – and GI Malabsorption - Also Increase Risk for CKD Incident CKD Risk vs. Baseline Methodology • Largest population-based study on the Urinary Oxalate & GI Malabsorption relationship of urinary oxalate levels and incident All Subjects CKD to date 3.0 Malabsorption Condition • Dataset includes 426,896 patients without CKD at 2.5 baseline and includes 12,522 with GI malabsorption 2.0 1.5 Findings • Among patients without a history of CKD, higher 1.0 urine oxalate is associated with higher risk of 0.5 developing incident CKD 0.0 • Prevalence of CKD was twice as high in patients with UOx > 80 mg/d compared with < 20 mg/d • Risk is substantially higher among those with an Baseline UOx underlying malabsorptive condition © 2022 SYNLOGIC. PROOF OF CONCEPT FOR SYNB8802 IN EH. ALL RIGHTS RESERVED. Puurunen et al, Data presented at ASN in November 2021 <20 20-29 30-39 40-44 45-49 50-59 60-69 70-79 80+ MV Odds Ratio


Hyperoxaluria May Have Genetic or Enteric Etiology Primary Hyperoxaluria (PH) Enteric Hyperoxaluria (EH) Pathology Rare genetic condition Dietary oxalate hyperabsorption Onset Pediatric Adult Underlying insult to bowel: including IBD, Etiology Genetic liver enzyme deficiency bariatric surgery, other chronic GI conditions 90 – 500 mg / 24 hrs 45 – 130 mg / 24 hrs UOx. Levels (~10x normal) (~3x normal) Number of Patients Affected © 2022 SYNLOGIC. PROOF OF CONCEPT FOR SYNB8802 IN EH. ALL RIGHTS RESERVED.


Clinical Path: Differential Diagnosis to Enteric Hyperoxaluria Etiology of Oxalate Clinical Presentation Stone Composition Malabsorption Source of GI Injury Other Genetic High Risk of Recurrent Kidney Calcium Oxalate Stones Surgery Idiopathic 1 Stones (“annual stone 1 formers”) 2 Enteric IBD/Crohn’s 2 Other Medical (e.g. CF) 1,2 Estimated U.S. Population: (>3mm) x (~75%) x (~10%) = ~200,000-300,000 1. Ziemba 2017 2. Synlogic 2022 Qualitative Market Research & Real World Evidence analyses by Trinity Partners © 2022 SYNLOGIC. PROOF OF CONCEPT FOR SYNB8802 IN EH. ALL RIGHTS RESERVED.


Today, Treatment for EH is Limited to Dietary Restrictions Stone Etiology Current Management Strategy Low Volume Increase fluid intake Ø Modest efficacy Hypocitraturia Citrate supplements Ø Avoids healthy foods (e.g. green vegetables) Low oxalate diet, calcium supplements, Hyperoxaluria Ø Calcium supplements can change IBD Tx (if applicable) exacerbate hypercalciuria May include low sodium diet or thiazide Ø Treatment is even less effective Hypercalciuria diuretics for enteric hyperoxaluria High Uric Acid Increase fluid intake Source: Synlogic 2022 Qualitative Market Research, In-depth interviews with U.S. © 2022 SYNLOGIC. PROOF OF CONCEPT FOR SYNB8802 IN EH. ALL RIGHTS RESERVED. stone clinic physicians treating patients with recurrent stones


Proof of Concept Data for SYNB8802 Caroline Kurtz, PhD. Chief Development Officer © 2022 SYNLOGIC. PROOF OF CONCEPT FOR SYNB8802 IN EH. ALL RIGHTS RESERVED.


SYNB8802: Consuming Oxalate in the GI Tract to Prevent Absorption Our Approach Precision Engineering of Probiotic Oral therapy Consume oxalate in the GI tract Gut lumen Intestinal epithelium Reduce oxalate in the urine Consumes Oxalate Throughout GI Tract © 2022 SYNLOGIC. PROOF OF CONCEPT FOR SYNB8802 IN EH. ALL RIGHTS RESERVED. GI = gastrointestinal


SYNB8802 Differentiation: Targeting Oxalate Throughout the GI Tract Oxalate Absorption ABSORPTION SITES OF ACTION Dietary Oxalate Healthy Disease State State Stomach • SYNB8802 consumes oxalate throughout Small Intestine the GI tract • Extends duration of action, increasing Colon oxalate-lowering efficacy potential © 2022 SYNLOGIC. PROOF OF CONCEPT FOR SYNB8802 IN EH. ALL RIGHTS RESERVED. GI=gastrointestinal


SYNB8802-CP-002 Phase 1b Study Design Phase 1b Study Design Randomized, placebo-controlled Day -3 -2 -1 1 2 3 4 5 6 7 8 9 10 11 12 parallel arm, in-patient study Treatment Treatment Primary endpoint: safety and tolerability 11 11 3 x 10 1 x 10 Placebo Treatment Controlled diet: Standardized dietary Run-In 1 oxalate intake Placebo Patient population: prior Roux-en-Y gastric bypass, with abnormal GI ◉ ◉ ◉ ◉ ◉ ◉ ◉ ◉ ◉ ◉ ◉ ◉ ◉ ◉ ◉ physiology typical of EH Frequency ◉ ◉ ◉ ◉ ◉ ◉ ◉ ◉ ◉ ◉ ◉ ◉ ◉ ◉ ◉ ◉ ◉ ◉ ◉ ◉ ◉ ◉ ◉ ◉ Disposition: 11 patients, 7 received 24h urine SYNB8802 and 4 received placebo, 1 patient discontinued during Daily collections Plasma placebo treatment Fecal 1 Meals contained an average level of oxalate and low calcium, divided over 3 meals a day during in patient stay © 2022 SYNLOGIC. PROOF OF CONCEPT FOR SYNB8802 IN EH. ALL RIGHTS RESERVED.


Urinary Oxalate Levels Show Dose-Related Change with SYNB8802 Urinary Oxalate Values During Dosing Period* Phase 1b SYNB8802-CP-002 Study 40 • Urinary oxalate levels at screening were consistent with 30 diet and patient population (at ~30), and generally remained consistent with baseline values during the 20 treatment period for placebo patients 10 • For both treatment periods, at both dose levels, dose- related reduction in urinary oxalate levels in response to SYNB8802 were observed 0 11 11 * Per pharmacometrics analysis including data from 7 patients receiving SYNB8802 at both the 1x10 and 3x10 dose levels and 4 patients receiving placebo © 2022 SYNLOGIC. PROOF OF CONCEPT FOR SYNB8802 IN EH. ALL RIGHTS RESERVED. Pbo 11 1x10 11 3x10 Urinary Oxalate (mg/24h) during Treatment Period


POC Achieved by Lowering of Urinary Oxalate SYNB8802 Urinary Oxalate Lowering vs. Baseline Compared to Placebo* Phase 1b SYNB8802-CP-002 Study 0% • Findings demonstrate that by consuming oxalate in the GI tract to prevent its absorption, SYNB8802 resulted in changes -20% in urinary oxalate in gastric bypass -28.3 patients -37.8 -40% * • Data analyzed using a pharmacometric model that enabled use of data from all * patients on all study days -60% 11 11 * Per pharmacometrics analysis including data from 7 patients receiving SYNB8802 at both the 1x10 and 3x10 dose levels and 4 patients receiving placebo CFB=change from baseline, CFP=change from placebo © 2022 SYNLOGIC. PROOF OF CONCEPT FOR SYNB8802 IN EH. ALL RIGHTS RESERVED. 11 1x10 11 3x10 %Change Urinary Oxalate CFB, CFP


Safety and Tolerability Findings SYNB8802 – Proof of Concept from 002 Study Top-Line Results • SYNB8802 was well tolerated, with no serious adverse events • The most common adverse events were GI-related, mild, and transient • The GI-related AEs occurred at a similar frequency in active and placebo groups • One patient in the placebo group discontinued during dosing due to the need for antibiotics © 2022 SYNLOGIC. PROOF OF CONCEPT FOR SYNB8802 IN EH. ALL RIGHTS RESERVED.


SYNB8802: Proof of Concept Achieved, Focused Path Forward • EH: Well-recognized burden of recurrent stones, with no FDA approved specific medical treatment options • SYNB8802: POC data shows potential for a powerfully differentiated treatment • Dose related lowering of UOx established in patients with gastric bypass • Validated mechanism of metabolizing oxalate in GI tract to prevent its absorption 11 11 • Both 1x10 and 3x10 doses exceeded -20% threshold for clinically meaningful reduction in recurrent 11 stone risk, with urinary oxalate lowering of -38% vs. placebo at the 3x10 dose TID • Enriched, concentrated target patient population: EH with highly recurrent stones • Profoundly affected by pain, interventions of recurrent stones • Connected to specialists (e.g. stone clinics) • Path forward: plan to advance towards registrational trial, likely clinical endpoint of stone disease progression © 2022 SYNLOGIC. PROOF OF CONCEPT FOR SYNB8802 IN EH. ALL RIGHTS RESERVED.


Cross-Platform Implications Dave Hava, PhD Chief Scientific Officer © 2020 SYNLOGIC. QU ARTE R LY R ES U LT S.A LLRIG H TS RESERVED .| 3 © 201 9 SY NLO G IC. ALL RI G HTS RESERVE D. | 3 © 2022 SYNLOGIC. PROOF OF CONCEPT FOR SYNB8802 IN EH. ALL RIGHTS RESERVED.


SYNB8802 POC: A Milestone for Synthetic Biotic Platform rd ü 3 positive data readout in 4Q 2022, following proof of concept in PKU, and proof of mechanism in HCU ü 2nd disease state with POC achieved ü Platform experience accelerates learnings, for dosing, tolerability © 2022 SYNLOGIC. PROOF OF CONCEPT FOR SYNB8802 IN EH. ALL RIGHTS RESERVED.


Concluding Remarks Dr. Aoife Brennan President & CEO © © 2 20 02 22 2 SY SYN NLO LOG GIIC C.. P PR RO OO OF F O OF F C CO ON NC CE EP PT T F FO OR R SY SYN NB B8 88 80 02 2 IIN N E EH H.. A ALL R LL RIIG GH HT TS R S RE ESE SER RV VE ED D..


Advancing a New Class of Biotherapeutics IND- Exploratory Preclinical Enabling Phase 1 Phase 2 Phase 3 Studies Phenylketonuria (PKU) FT SYNB1934* ODD (US) ODD SYNB1353 FT ODD Homocystinuria (HCU) SYNB8802 (US) Metabolic SYNB8802 Enteric Hyperoxaluria ODD Gout SYNB2081 Inflammatory Bowel Disease (IBD) Combo study late ‘21 Immunology IBD Program - Single Target FT = Fast Track granted by FDA ODD = Orphan Drug Designation granted by FDA *First generation SYNB1618 for PKU received both ODD and FT designations by the FDA and orphan medicinal product designation by the EMA.


Available For Questions Aoife Brennan, MB ChB Caroline Kurtz, PhD Dave Hava, PhD Kyle Wood, MD President & CEO Chief Development Officer Chief Scientific Officer Associate Professor, Urology, University of Alabama at Birmingham Michael Jensen Molly Harper Antoine Awad Chief Financial Officer Chief Business Officer Chief Operating Officer © 2022 SYNLOGIC. PROOF OF CONCEPT FOR SYNB8802 IN EH. ALL RIGHTS RESERVED.


Thank You © 2022 SYNLOGIC. PROOF OF CONCEPT FOR SYNB8802 IN EH. ALL RIGHTS RESERVED. © 2022 SYNLOGIC. PROOF OF CONCEPT FOR SYNB8802 IN EH. ALL RIGHTS RESERVED.