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SYBX US Equity

Synlogic, Inc.Health Care · Pharmaceutical Preparations · CIK 1527599 · FY ends Dec 31
$1.20
+0.00 (+0.00%)
USD · as of 2026-08-18 · marketstack

SYBX · 10-K · period ended 2024-12-31

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filed 2025-03-06 · EDGAR original ↗

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10-K

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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-K

(Mark One)

☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the fiscal year ended December 31, 2024

OR

☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 FOR THE TRANSITION PERIOD FROM TO

Commission File Number 001-37566

SYNLOGIC, INC.

(Exact name of Registrant as specified in its Charter)

(Address of principal executive offices) (Zip Code)

(617) 659-2802

(Registrant’s telephone number, including area code)

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

Title of each class Trading Symbol Name of exchange on which registered

Common Stock, par value $0.001 per share SYBX The Nasdaq Capital Market

Preferred Stock Purchase Rights N/A The Nasdaq Capital Market

Securities registered pursuant to Section 12(g) of The Act:

None

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Yes☐No☒

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or 15(d) of the Act. Yes☐No☒

Indicate by check mark whether the registrant: (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.Yes☒No☐

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). Yes☒No☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

Large accelerated filer ☐ Accelerated filer ☐

Non-accelerated filer ☒ Smaller reporting company ☒

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. ☐

Indicate by check mark whether the registrant has filed a report on and attestation to its management’s assessment of the effectiveness of its internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C. 7262(b)) by the registered public accounting firm that prepared or issued its audit report. ☐

If securities are registered pursuant to Section 12(b) of the Act, indicate by check mark whether the financial statements of the registrant included in the filing reflect the correction of an error to previously issued financial statements. ☒

Indicate by check mark whether any of those error corrections are restatements that required a recovery analysis of incentive-based compensation received by any of the registrant’s executive officers during the relevant recovery period pursuant to §240.10D-1(b). ☒

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). YES ☐ NO ☒

The aggregate market value of common stock held by non-affiliates of the registrant as of June 28, 2024, the last business day of the registrant’s most recently completed second quarter, was $4.1 million, computed based on the closing price of $1.50 per share on June 28, 2024.

As of February 27, 2025 there were 11,696,109 shares of the registrant’s common stock, par value $0.001 per share, outstanding.

DOCUMENTS INCORPORATED BY REFERENCE

The following documents (or parts thereof) are incorporated by reference into the following parts of this Form 10-K: Certain information required in Part III of this Annual Report on Form 10-K is incorporated from the registrant’s definitive proxy statement for the 2025 annual meeting of stockholders to be filed pursuant to Regulation 14A with the U.S. Securities and Exchange Commission within 120 days of the registrant’s fiscal year ended December 31, 2024.

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Table of Contents

Page

PART I

Item 1. Business 2

Item 1A. Risk Factors 37

Item 1B. Unresolved Staff Comments 75

Item 1C. Cybersecurity 75

Item 2. Properties 77

Item 3. Legal Proceedings 77

Item 4. Mine Safety Disclosures 77

PART II

Item 6. [Reserved] 78

Item 7A. Quantitative and Qualitative Disclosures About Market Risk 89

Item 8. Financial Statements and Supplementary Data 89

Item 9A. Controls and Procedures 90

Item 9B. Other Information 91

Item 9C. Disclosure Regarding Foreign Jurisdictions that Prevent Inspections 91

PART III

Item 10. Directors, Executive Officers and Corporate Governance 92

Item 11. Executive Compensation 92

Item 14. Principal Accounting Fees and Services 92

PART IV

Item 15. Exhibits, Financial Statement Schedules 93

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FORWARD-LOOKING STATEMENTS

This Annual Report on Form 10-K contains forward-looking statements that involve risks and uncertainties. We make such forward-looking statements pursuant to the safe harbor provisions of the Private Securities Litigation Reform Act of 1995 and other federal securities laws. All statements other than statements of historical facts contained herein are forward-looking statements. In some cases, you can identify forward-looking statements by terminology such as “may,” “will,” “should,” “expects,” “intends,” “plans,” “anticipates,” “believes,” “estimates,” “predicts,” “potential,” “continue” or the negative of these terms or other comparable terminology. These forward-looking statements include, but are not limited to, statements about:

our evaluation of strategic alternatives with a goal to enhance stockholder value, including the possibility of a merger or a sale of the Company;

the success of our research and development efforts;

the initiation, progress, timing, costs and results of clinical trials for our product candidates;

the time and costs involved in obtaining regulatory approvals for our product candidates;

the success of our collaborations with third parties;

the progress, timing and costs involved in developing manufacturing processes and in manufacturing products, as well as agreements with third-party manufacturers;

the rate of progress and cost of our commercialization activities;

the expenses we incur in marketing and selling our product candidates, if approved;

the revenue generated by sales of our product candidates, if approved;

the emergence of competing or complementary technological developments;

the terms and timing of any additional collaborative, licensing or other arrangements that we may establish;

the acquisition of businesses, products and technologies;

our need to implement additional infrastructure and internal systems;

our need to add personnel and financial and management information systems to support our product development and potential future commercialization efforts, and to enable us to operate as a public company;

the extent to which our business is adversely impacted by the effects of the coronavirus outbreak (COVID-19) or by other health epidemics or pandemics; and

other risks and uncertainties, including those listed under Part I, Item 1A. “Risk Factors.”

Any forward-looking statements in this Annual Report on Form 10-K reflect our current views with respect to future events or to our future financial performance and involve known and unknown risks, uncertainties and other factors that may cause our actual results, performance or achievements to be materially different from any future results, performance or achievements expressed or implied by these forward-looking statements. Factors that may cause actual results to differ materially from current expectations include, among other things, those listed under Part I, Item 1A. “Risk Factors” and elsewhere in this Annual Report on Form 10-K. Given these uncertainties, you should not place undue reliance on these forward-looking statements. Except as required by law, we assume no obligation to update or revise these forward-looking statements for any reason, even if new information becomes available in the future.

This Annual Report on Form 10-K also contains estimates, projections and other information concerning our industry, our business, and the markets for certain diseases, including data regarding the incidence and prevalence of certain medical conditions. Information that is based on estimates, forecasts, projections, market research or similar methodologies is inherently subject to uncertainties and actual events or circumstances may differ materially from events and circumstances reflected in this information. Unless otherwise expressly stated, we obtained this industry, business, market and other data from reports, research surveys, studies and similar data prepared by market research firms and other third parties, industry, medical and general publications, government data and similar sources.

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PART I

Item 1. Business.

Overview

We are a biopharmaceutical company that 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 Committee (DMC) assessment, which indicated the trial was unlikely to meet its primary endpoint. The decision was not based on concerns regarding safety or tolerability. As a result, our current corporate strategy is focused on pursuing strategic initiatives to enhance stockholder value, including but not limited to, a merger or the sale of the Company. Our strategic process is both active and ongoing and includes a range of interactions with transaction counterparties. Thus, we believe it is in our stockholders’ best interest to allow sufficient opportunity to pursue and consummate one or more such transactions and to consider additional alternatives that may materialize in the future. However, there can be no assurance that such activities will result in any agreements or transactions that will enhance shareholder value. Further, any strategic transaction that is completed ultimately may not deliver the anticipated benefits or enhance shareholder value.

Our early-stage pipeline included product candidates for enteric hyperoxaluria, gout, and cystinuria, and was fueled by a reproducible, proprietary approach that created GI-restricted, oral medicines with new enzymatic pathways designed to consume or produce specific biological targets. We design, develop and manufacture these drug candidates, which are produced by applying genetic engineering to well-characterized probiotics.

Our drug candidates are designed through precise engineering to target validated biological pathways in the pathophysiology of a given disease. By using a probiotic to deliver these new enzymatic pathways, the activity is restricted to the gastrointestinal (GI) tract, avoiding systemic exposure and associated risks that limit the success of other modalities. Our pipeline programs are all based on the same probiotic Escherichia coli Nissle 1917, which provides synergies across programs, as well as more than one hundred years of human dosing experience. Our drug candidates are engineered to be non-colonizing, and fully reversible via GI clearance. These potential biopharmaceuticals are all orally administered, conducive to straightforward shipping, distribution and storage. For manufacturing, our platform leverages processes with familiar foundations, including fermentation and lyophilization, facilitating process design and scale-up, combined with unique and proprietary innovations tailored to our unique products.

Since our founding, based upon technology from the Massachusetts Institute of Technology (MIT) in 2014, we progressed a pipeline of multiple drug candidates across different stages, including:

Labafenogene marselecobac (SYNB1934), which was being studied in Synpheny-3, a pivotal, Phase 3 study for the treatment of patients with PKU;

SYNB1353, a potential treatment for HCU, has achieved proof of mechanism in a Phase 1 study in healthy volunteers;

Preclinical research activities on a potential drug candidate for cystinuria, a rare, genetic cause of recurrent kidney stones which is also caused by an underlying metabolic disorder;

SYNB2081, a drug candidate for gout which was in IND-enabling studies; and

Preclinical research focused on novel, locally-acting, GI-restricted biotherapeutics for indications in inflammatory bowel disease (IBD).

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Strategy

As announced in February 2024, our current corporate strategy is focused on pursuing strategic initiatives to enhance stockholder value, including by exploring a range of alternatives including but not limited to a merger or the sale of the Company. Our strategic process is both active and ongoing and includes a range of interactions with transaction counterparties. Thus, we believe it is in our stockholders’ best interest to allow sufficient opportunity to pursue and consummate one or more such transactions and to consider additional alternatives that may materialize in the future. However, there can be no assurance that such activities will result in any agreements or transactions that will enhance shareholder value. Further, any strategic transaction that is completed ultimately may not deliver the anticipated benefits or enhance shareholder value.

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. Historically, our mission was to treat diseases underserved by other modalities by researching, developing and commercializing new medicines.

Our Pipeline: Synthetic Biotics in Clinical Development

Our product pipeline consisted of drug candidates targeting significant medical needs caused by an underlying metabolic disorder. These include labafenogene marselecobac, which was being evaluated in a pivotal, Phase 3 study in PKU, and drug candidates designed to treat HCU, enteric hyperoxaluria, and gout. Our preclinical work includes additional metabolic disease research, including cystinuria, target exploration, and focused research efforts in IBD.

Clinical Pipeline: Focus on Rare Metabolic Diseases

Rare metabolic diseases often result from inherited defects or alterations in specific enzymes or other biological pathways that normally break down or produce important metabolites or molecules. In patients with these diseases, the absence or impairment of certain enzymes causes potentially toxic metabolites to accumulate. In patients with PKU and HCU, the build-up of these metabolites can reach toxic levels, resulting in life-threatening medical risks and/or serious developmental delays, life-altering disease burden and symptoms. While there are approved and available pharmaceutical products for both diseases, they present significant limitations in terms of both safety and efficacy, leaving patients often under-managed, attempting to control their disease through a restrictive regimen of diet, medical formula and medical foods, and/or experiencing significant symptoms or risk of dangerous complications.

Market Opportunity

In addition to significant need for new medical treatments, we believe rare metabolic diseases PKU and HCU present advantages as target therapeutic areas for investment. Despite their limitations, the approved treatments for these diseases provide useful precedent in terms of both clinical development paths and navigating regulatory processes including approval. For example, in both PKU and HCU, existing treatments were approved by global regulators based on clinical biomarkers as the primary endpoint in their pivotal, registrational trials, sufficient for full approval. All of the metabolic diseases that we target in our current pipeline also

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have the benefit of a dietary model, in which there is already a standard dietary intervention to reduce the target metabolite (e.g. avoiding protein in the case of PKU to lower Phe levels, or methionine in the case of HCU, or uric acid for gout). These existing dietary interventions provide a useful model by demonstrating that GI-based means of lowering metabolite levels to provide therapeutic benefit.

From a commercial perspective, these rare metabolic diseases have been well-characterized, and while limited in uptake due to their limitations, the currently available products have provided commercial validation. In PKU for example, the two approved products, Kuvan and Palynziq, have generated $500 million and $300 million respectively, in annual revenue as branded agents, translating to a market opportunity we estimate to be more than $3 billion. For HCU, with an estimated 5,000 patients globally, we estimate a potential market opportunity to be more than $1 billion.

Further, these two disease states present significant synergies as target indications. PKU and HCU patients are largely both treated by the same, concentrated and group of specialist clinicians at metabolic clinics, facilitating both late-stage development and commercialization, given the overlap in key opinion leaders (KOLs), medical meetings and congresses, as well as call points for sales and marketing, market access and patient support programming.

Our PKU Program

Our lead product candidate, labafenogene marselecobac (SYNB1934), which was being evaluated in Synpheny-3, a privotal Phase 3 study, is designed to consume phenylalanine (Phe) through engineered enzymes produced within the probiotic, E. coli Nissle. Labafenogene marselecobac has received Orphan Drug Designation (ODD), Fast Track designation, and Rare Pediatric Disease Designation (RPDD) from the FDA in addition to orphan designation from the European Medicines Agency (EMA). In 2023 we announced that the International Nonproprietary Names (INN) Expert Committee of the World Health Organization (WHO-INN) has selected "labafenogene marselecobac" for the nonproprietary name of SYNB1934, reflecting a naming framework for genetically engineered bacteria, in which the first name references the gene being designed or modified (in this case, one for Phe or “fe”), and the second references the bacteria (“bac”).

The Science of PKU

PKU is an inherited metabolic disease caused by genetic mutations that impair the function of the enzyme, phenylalanine hydroxylase (PAH), which normally metabolizes phenylalanine (Phe), an amino acid found in all protein-containing foods, including all meat and dairy products, most beans, grains and potatoes, as well as some artificial sweeteners. Without functioning PAH, uncontrolled Phe levels in PKU can be neurotoxic, interfering with normal brain development during childhood, causing permanent developmental disabilities; severely elevated Phe levels at any age can result in neurocognitive symptoms such as slower cognition, difficulty concentrating or “brain fog.”

Reducing the risk of complications and neurocognitive symptoms in PKU patients requires lifelong control of Phe levels. During the 1960’s, countries began newborn screening to ensure that Phe control was implemented immediately through a highly restrictive, low-Phe diet accompanied by supplemental formula for needed amino acids to avoid permanent, severe intellectual disability. Per E.U. and U.S. guidelines, any newborn infant with a plasma Phe concentration of >400–600 μM should be started on a low-Phe diet as soon as possible. The diet includes extreme restrictions of natural foods to keep daily protein at levels that are often as low as 4-6 grams per day for adults. This generally includes elimination of all sources of animal protein and dairy, legumes and nuts, and limited intake of bread, pasta, rice and some vegetables. Low-protein bread and pasta products made from starch are used to provide needed energy. The dietary regimen required also includes the addition of amino acid-based, Phe-free formula or other specific medical foods to provide adequate protein, vitamins, minerals and energy.

It is challenging for persons to adhere to this restricted diet and its associated requirements create significant burdens on quality of life for both patients and caregivers. Access to low protein foods can pose difficulties as they are costlier and less nutritious than their higher protein, non-modified equivalents, and the needed formula can also be costly or otherwise difficult to access. As a result, the vast majority of people living with PKU, and especially adults living independently, have Phe levels well above the recognized targets.

It is estimated that there are more than 150,000 people diagnosed with PKU living across the United States, Europe and Asia. They are typically diagnosed through newborn screening. Of these, the vast majority remain untreated, reflecting the limitations of current treatment options.

Limitations of Current PKU Treatment Options

There are currently two medications been approved by the FDA, EMA, and other regulatory agencies globally as medical treatments for PKU based on safety and efficacy in reduction of plasma Phe levels. These approved medications provide important and helpful examples and precedents for clinical development and regulatory processes. Each one however, has drawbacks limitations leave the majority of people with PKU living without a medical treatment for Phe reduction. These limitations are outlined below:

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Sapropterin dihydrochloride (Kuvan®), a biopterin, was approved by the FDA in 2017, and is now available as a generic in the United States and other markets in tablet and sachet formulations. Sapropterin works by stimulating the PAH enzyme to process Phe in people with PKU. This requires having residual PAH enzyme, and responding to tetrahydrobiopterin (BH4). Typically only a minority of PKU patients will demonstrate BH4-responsiveness, and as a result, the use of Kuvan has been limited to an estimated 15%-20% of U.S. patients. Reflecting the size of the overall patient population, despite this low use, Kuvan generated ~$500 million per year globally for BioMarin Pharmaceutical, Inc. prior to genericization. Of those who do respond and maintain treatment with sapropterin, we believe a significant proportion would still benefit from additional Phe-lowering, and see this segment as an important opportunity for labafenogene marselecobac as an adjunctive medical treatment option.

Palynziq® Injection (pegvaliase-pqpz) was approved by the FDA in 2018 for adult patients with PKU and uncontrolled blood Phe. Due to instability and other complexities, the PAH enzyme that is impaired in PKU is not a viable candidate for enzyme replacement therapy. Palynziq is a pegylated form of recombinant phenylalanine ammonia lyase (PAL), a non-mammalian enzyme that also metabolizes Phe. Safety considerations include risk of severe allergic reactions, including a 10% risk of anaphylaxis, resulting in FDA labeling that includes a boxed warning and requirement to carry auto-injectable epinephrine at all times while they are taking the medication. Despite these challenges, Palynziq is forecast to generate $300 million in 2023, largely from the United States, despite maintaining an estimated ~10% market share.

Given the limitations of sapropterin in terms of responder rates, and the safety challenges of Palynziq, we believe the approved therapies’ limitations leave a large majority of those living with PKU in need of an orally-administered medical treatment option that provides Phe-lowering efficacy with an acceptable safety and tolerability profile.

Labafenogene marselecobac for PKU

Labafenogene marselecobac is designed to treat PKU and lower Phe levels through the engineering of two Phe-consuming enzymes: L-amino acid deaminase (LAAD) and phenylalanine ammonia lyase (PAL), produced by a strain of E. coli Nissle, which also includes a Phe transporter, PheP, to bring Phe into the cell. The drug candidate thustargets Phe from dietary sources, and Phe that has circulated to the GI tract via enterorecirculation.

This design enables a patient-friendly product presentation: it is provided to patients as powder for mixing with water or juice, taken with with meals. This product presentation is familiar to PKU patients, as sapropterin is provided as a sachet, and often their nutritional supplemental formula requires mixing with liquid.

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Labafenogene marselecobac was engineered as a next-generation version of first-generation PKU drug candidate SYNB1618, by modifying five amino acids in PAL, which increased productivity of PAL’s conversion of Phe to the metabolic byproduct trans-Cinnamic acid (TCA). A detailed description of the engineering of SYNB1618 and data from preclinical studies in an animal model of disease and healthy non-human primates was published in 2018 (Nat. Biotechnol. 36, 857–864 (2018)), and an overview of the engineering and early development of SYNB1934 was published in 2021 (Nat Commun. 12, 6215 (2021)).

In Phase 1 studies of healthy volunteers, both SYNB1618 and labafenogene marselecobac were found to be safe and well-tolerated at doses up to 2x1012 live cells administered three times a day for seven days. Higher doses were associated with mild to moderate gastrointestinal symptoms, mainly nausea and vomiting. In July 2019, we announced data that demonstrated that SYNB1618 was safe and well-tolerated and achieved proof-of-mechanism of strain activity in both healthy volunteers and patients with PKU. Improved tolerability of the lyophilized SYNB1618 over the early liquid formulation enabled us to determine a maximally tolerated dose (MTD) to take forward to test in patients. In September 2021, we announced that Phase 1 results in healthy volunteers and predictive modeling indicate labafenogene marselecobac may have greater potency than SYNB1618.

In October 2022, we shared positive top-line results from the Phase 2 Synpheny-1 study that demonstrated proof of concept in PKU patients for both candidates, and confirmed greater potency of the next-generation labafenogene marselecobac , the candidate that we have selected to advance to pivotal Phase 3 studies. The complete results were presented at the Society for Inherited Metabolic Disorders (SIMD) Annual Meeting in March 2023 and published in the journal Nature Metabolism in September 2023. Results presented included successfully meeting the primary endpoint (change in area under the curve of D5-Phe following a meal challenge) for SYNB1618 and labafenogene marselecobac. Results for labafenogene marselecobac included a -40% mean reduction in plasma Phe levels for labafenogene marselecobac, and -53% among those considered responders (with >20% reduction from baseline). 60% of patients achieved the >20% criteria for Phe reduction considered the threshold for a clinically meaningful response. The study also included experience with both candidates when provided in combination for patients who were already taking sapropterin (Kuvan) at baseline, indicating the potential for adjunctive medical treatment. Safety and tolerability findings were consistent with prior

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experience and favorable, with no serious adverse events (SAE) across the PKU program, and those adverse events that did occur being predominantly GI in nature.

In June 2023 we announced the initiation of Synpheny-3. Its design was informed by input from global regulatory agencies, clinicians and patients, and the precedent of pivotal studies from already approved drugs.

The study was a randomized, placebo-controlled, global, pivotal Phase 3 clinical trial designed to evaluate the efficacy and safety of SYNB1934 as a treatment for PKU. The primary endpoint was the change in phenylalanine (Phe) levels from baseline for SYNB1934 compared to placebo, in a subset of patients who are considered responders (defined as >20% reduction in Phe).

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The trial consisted of three parts: Part 1, an open-label dose escalation period, during which patients titrate through up to three dose levels, with at least three weeks per dose; Part 2, a four-week randomized withdrawal period used for the pivotal analysis; and Part 3, an open-label extension which includes an evaluation of Phe tolerance, or dietary liberalization.

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 Committee (DMC) assessment, which indicated the trial was unlikely to meet its primary endpoint. The decision was not based on concerns regarding safety or tolerability.

Our HCU Program

In November 2021 we announced the nomination of SYNB1353, a novel, orally administered, non-systemically absorbed drug candidate designed to lower plasma levels of homocysteine (Hcy) in patients with HCU by consuming methionine (Met), a precursor to Hcy. We also shared at that time that mechanistic modeling data suggests that SYNB1353 may lower plasma Hcy by up to 58% and may increase protein intake in HCU patients.

In November 2022, we announced that proof of mechanism was achieved with SYNB1353 through positive results in the Phase 1 study of healthy volunteers using a dietary model of HCU, in which we showed the translation from SYNB1353’s activity in the GI tract to a lowering of plasma levels of Met. SYNB1353 has received Fast Track, Orphan Drug, and Rare Pediatric Disease Designations from the FDA as a potential treatment for HCU.

Science of HCU

HCU is a rare inherited metabolic disorder that affects the metabolism of the amino acid methionine (Met), a protein found in many foods including meat, fish, and dairy products. HCU is caused by a genetic defect which results in the absence of an enzyme known as cystathionine beta-synthase (CBS). When CBS is absent, Hcy and other toxic chemicals and their byproducts, including Met, build up in the blood and urine. In HCU, elevated total homocysteine (tHcy) levels are associated with a multisystem disorder, including impairments of the eye (ectopia lentis and/or severe myopia), skeletal system (excessive height, long limbs, scoliosis, pectus excavatum), vascular system (thromboembolism), and CNS (development delay and intellectual disability). The goal in treating HCU

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is to reduce and control levels of tHcy, thereby reducing risk of acute, potentially life-threatening blood clots and chronic, multisystem complications.

There is currently no cure for HCU and treatment options are limited. Patients must follow a rigid diet low in protein to avoid dietary Met intake. Other therapeutic approaches include vitamin supplements to minimize some of the disease side effects. Approximately 5,000 individuals in the United States and Europe suffer from CBS or “Classical” HCU.

Limitations of Current HCU Treatments

Approved pharmacological treatment options for HCU are limited due to efficacy and tolerability. People with more mild phenotypes of HCU typically respond effectively to, and are sufficiently managed by, taking Vitamin B6 (also known as pyridoxine-responsive). Non-responders require a combination of betaine (brand name Cystadane®) and a moderate to severe dietary Met restriction. The severely protein-restricted diet is complex and challenging for long-term adherence. Compliance with treatment often deteriorates, particularly in adolescence, as in other disorders requiring dietary adherence. Patients report significant challenges with the burden of the low protein diet, intake of amino acid mixtures, and the palatability of protein substitutes as well as betaine. Reaching tHcy treatment targets remains a challenge despite existing pharmacotherapies.

SYNB1353 for HCU

A diet low in Met, a precursor to Hcy, is standard treatment for lowering tHcy levels in patients with HCU. This dietary model provided the scientific rationale for SYNB1353, which was engineered to produce an enzymatic pathway to metabolize Met, and thus lower plasma levels of tHcy. SYNB1353 metabolizes Met via the methionine decarboxylase (MetDC) enzymatic pathway, which prevents the conversion of Met into Hcy, thereby lowering tHcy in HCU patients and reducing risk of complications. SYNB1353 is taken as an orally administered, non-systemically absorbed live biotherapeutic drug candidate that, like our PKU drug candidates, is provided as a lyophilized powder in a sachet, to be orally administered with meals three times a day. We hold

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worldwide development and commercialization rights to SYNB1353, which was developed as part of our research collaboration with Ginkgo.

In November 2022, we announced that proof of mechanism was achieved with SYNB1353 through positive results in the Phase 1 study of healthy volunteers using a dietary model of HCU. Top-line results demonstrated that SYNB1353 reduced in plasma Met when measured over 24 hours as area under the curve (AUC) following a Met meal challenge. SYNB1353 was generally well tolerated, and adverse events (AEs) were all mild to moderate, transient, and predominantly GI in nature. The frequency and severity of GI-related AEs were similar in the active and control group. During 2023, we conducted fermentation process improvements that successfully further increased activity of methionine degradation for SYNB1353.

Clinical Pipeline: Earlier-Stage Programs

Our Enteric Hyperoxaluria Program

SYNB8802 is a novel, orally administered, non-systemically absorbed drug candidate that was being developed for the treatment of enteric hyperoxaluria, a chronic, progressive disease characterized by high levels of urinary oxalate (Uox), a well-recognized cause of recurrent kidney stones.

Hyperoxaluria is a disease which results from excessive levels of oxalate in the body. Oxalate can be found naturally in the body or in foods with high oxalate levels such as leafy greens, potatoes, almonds, coffee, and beans. Humans do not have an inherent physiological need for oxalate and it is normally excreted through the kidney. Excessive levels of oxalate, when present in the urine, bind with calcium in the kidney and lead to nephrolithiasis (kidney stone formation), nephrocalcinosis, chronic kidney complications and renal disease.

Enteric hyperoxaluria often occurs as a result of a primary insult to the bowel, such as Crohn’s disease, short bowel syndrome, or surgical procedures such as Roux-en-Y bariatric weight-loss surgery. This results in GI malabsorption, causing increased absorption of oxalate across the GI tract into the circulation. Oxalate crystals can damage kidneys, leading to chronic kidney disease and end-stage renal disease (ESRD). There are no approved treatments for enteric hyperoxaluria.

There is a direct link between elevated Uox and increased probability of kidney stone events or other renal adverse outcomes in patients with enteric hyperoxaluria. Even modest reductions in Uox can reduce the odds of developing a kidney stone. A recent epidemiological study conducted in 297 patients with enteric hyperoxaluria demonstrated that a 20% reduction in Uox resulted in as

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much as a 25% reduction in the annual risk of having a kidney stone in the subsequent year in patients with recurrent kidney stones (D’Costa, Nephrol Dial Transplant 2020).

There are currently few approved treatments for primary hyperoxaluria, a rare genetic disease wherein the liver produces excessive levels of oxalate. Approved treatments for primary hyperoxaluria target the liver, and thus are not beneficial to patients with enteric hyperoxaluria, given its etiology is in GI malabsorption, and not hepatic over-production.

We estimate that there are 200,000 to 300,000 patients with recurrent kidney stones due to enteric hyperoxaluria in the United States. Existing treatment options are generally non-specific and include high fluid intake to increase urine output to more than two to three liters per day, a diet low in salt and oxalate, oral citrate and/or calcium and/or magnesium supplementation. We believe a clear need exists for therapies that lower dangerously high levels of Uox to reduce the risk of recurrent kidney stones in this patient population.

In May 2020, we announced the nomination of a clinical candidate for enteric hyperoxaluria, SYNB8802, which was designed using precision genetic engineering of E. coli Nissle to lower Uox levels by consuming oxalate throughout the GI tract through the addition of three different enzymes. In vivo studies in both mice and non-human primates demonstrated that SYNB8802 decreased Uox levels in an acute model of hyperoxaluria induced by dietary intervention. A detailed description of the engineering of SYNB8802 and data from these preclinical studies in an animal model of disease and healthy non-human primates was published in Molecular Systems Biology (Lubkowicz et al 2022). In 2021, we reported positive proof-of-mechanism for SYNB8802 from a Phase 1b study that demonstrated lowering of urinary and fecal oxalate levels in healthy volunteers with diet-induced hyperoxaluria, and in December 2022, we shared data confirming that SYNB8802 demonstrated proof of concept through clinically significant -38% lowering of Uox in a Phase 1b study in patients with a history of gastric bypass surgery.

Our Gout Program

SYNB2081 is designed to consume uric acid in the GI tract with the goal of lowering systemic uric acid levels as a potential treatment for gout, a complex form of inflammatory arthritis. Current treatment options present limitations in both safety and efficacy. SYNB2081 presents a novel, orally administered, non-systemically absorbed drug candidate created through our research collaboration with Ginkgo.

Gout occurs when excess uric acid in the body forms crystals in the joints. Patients can experience symptoms such as intense joint pain, inflammation and redness, and limited range of motion in the affected joints due to excessive levels of uric acid. In addition, gout is a recognized risk factor in chronic kidney disease. Due to present limitations in current treatment options, we believe that there is a clear need for a new approach.

In August 2022 we announced SYNB2081 as our drug candidate for the potential treatment of gout and the second product to advance to clinical development through our collaboration with Ginkgo.

Designing and Developing Synthetic Biotics

The Synthetic Biotics we design have unique advantages as potentially safe, effective, orally administered biotherapeutics. Engineered microbes can be programmed to carry out functions that cannot be performed by conventional drug treatments, such as small molecules or antibodies. Unlike other targeted approaches such as gene or RNA-targeted therapies, Synthetic Biotics are reversible, as they are engineered to be non-colonizing and are rapidly cleared via excretion. They have a reduced risk of adverse events due to the lack of systemic absorption.

Using Synthetic Biology to Generate Synthetic Biotics

Bacteria have evolved over millions of years to adapt, survive, and actively metabolize to consume or produce metabolites in the human body. They are also amenable to genetic manipulation. To confer a therapeutic effect, we use basic biological properties of bacteria and the tools of synthetic biology to develop Synthetic Biotics from non-pathogenic microbes, focusing initially on a single strain of the bacteria E. coli Nissle.

Our scientists genetically engineer probiotic, non-pathogenic bacteria to create biological circuits to direct cellular processes in a manner analogous to designing electrical circuits. We aim to precisely and appropriately control the amount, location and activity of our Synthetic Biotics to address specific diseases and target biology of interest.

The critical parts of an engineered Synthetic Biotic medicine include (1) the chassis, or non-pathogenic bacterium (in our case E. coli Nissle), (2) the effector module(s), which is a gene or pathway encoding the core biological activity that provides the

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therapeutic function, and (3) tunable switches that are designed to respond to specific disease states or environment signals to precisely control the activity, potency, and performance of the effector modules.

1.

The Chassis: Our Synthetic Biotic platform starts with a well-characterized probiotic to serve as the chassis upon which we build our living medicines. Our research and development programs use E. coli Nissle, which is one of many non-pathogenic probiotics isolated from the human microbiota. E. coli Nissle is non-colonizing and has been used as a probiotic bacterial supplement for many years to promote gut health. Clinical studies have demonstrated that E. coli Nissle is rapidly cleared from most individuals with no significant safety issues (Clin. Transl. Sci. (2017) 00, 1—8). We also observed complete clearance from subjects in our Phase 1 clinical trial of SYNB1618 in healthy volunteers (Puurunen et al 2021 Nature Metabolism 3; 1125-1132). We believe E. coli Nissle's widespread use as a probiotic is evidence of its utility as a safe background chassis to apply synthetic biology to confer a therapeutic benefit. There are several additional features of E. coli Nissle organism that makes it an attractive chassis for our platform:

E. coli Nissle’s genetic and metabolic machinery are well understood and provide a robust cellular context into which genetic information can be introduced with high efficiency and little or no damage to the fitness of the bacterium.

The advanced nature of the synthetic biology toolkit available for E. coli Nissle enables rapid iterative design, assembly, and testing of prototype product candidates and remains unique among other bacterial and cellular engineering approaches.

Starting from known principles of manufacturing helps de-risk Synlogic’s proprietary large-scale manufacturing platform.

As a Gram-negative bacterium, with a protective outer wall, E. coli Nissle survives well in the human GI tract.

2.

The Effector Module or Circuit: Synthetic Biotics have the advantage that they can be designed with multiple pathway components. We have engineered integration systems to direct stable insertion of multiple genetic circuits and pathways into optimal chromosomal locations, or “landing pads,” of E. coli Nissle. This enables efficient and stable expression of multiple genes encoding enzymes and other proteins. Our approach allows us to engineer two types of mechanistic activities into our Synthetic Biotics: 1) we can engineer Synthetic Biotics capable of metabolic transformations that can substitute or compensate for missing or defective pathways in a patient, and 2) we can engineer Synthetic Biotics to produce therapeutically beneficial molecules.

The enzymatic pathways needed to produce or convert molecules are protected from the harsh GI environment by their location within the cell cytoplasm of E. coli Nissle, allowing them the potential to function throughout the GI tract. We have leveraged proprietary tools, know-how and intellectual property to build multiple Synthetic Biotics that produce therapeutically relevant effects in pre-clinical experiments. Progression of these product candidates in diseases with high unmet need is based on prioritizing those with feasible drug development paths in terms of availability of informative animal models and existence of biomarkers to guide efficient clinical development.

3.

Tunable Switches: We also design and engineer proprietary switches to control the activity of the genetic pathways we introduce into our Synthetic Biotics, with the goal of controlling the engineered circuit or its therapeutic output. To optimize the fitness and activity of a Synthetic Biotic, it is critical that the effector is activated at the appropriate time and

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place to mediate its function. Switches are based on engineering DNA elements called “inducible promoters” that are designed to respond to disease states, specific environmental signals, or exogenously added inducing molecules.

Advantages of Synthetic Biotic Biotherapeutics

We believe our Synthetic Biotics will provide safe and effective therapies given the following attributes:

1.

Synthetic Biotics Have Potential to Address Unmet Needs Not Possible with Other Modalities

Degrading Toxic Metabolites: Unlike other therapeutic approaches, Synthetic Biotics can be programmed with a unique mechanistic activity. For internal metabolic programs, we are engineering Synthetic Biotics with entire pathways designed to degrade or convert toxic metabolites. We believe that using a metabolizing pathway is advantageous compared to gene, RNA or enzyme replacement therapies because the latter are limited to targeting a single gene or protein defect and may require several unique drug products to address genetically heterogeneous patient populations. Compensating with an entire pathway delivered in bacteria Synthetic Biotics may provide a safe, therapeutic solution to broader disease populations as a single engineered therapeutic. Our clinical stage programs, SYNB1934, SYNB8802 and SYNB1353, are examples of Synthetic Biotics designed and engineered to eliminate metabolites from the GI tract and prevent their absorption.

Production of Therapeutic Molecules: Synthetic Biotics can also be programmed to produce beneficial molecules, such as bacterial metabolites that may improve disease or proteins that can be secreted from the bacteria into the local environment. Examples of this approach include production of short chain fatty acids (Reeves et al. DDW 2022), aryl hydrocarbon (AHR) agonists (Shu et al. DDW2022) and secretion of human IL-22 protein (Reeves et al. DDW 2022).

Combinations of Mechanisms: By incorporating multiple effectors or enzymes into a single strain, Synthetic Biotics have the potential to address multifactorial disease biology more effectively. For example, Synthetic Biotics can be engineered with multiple enzymes which convert toxic metabolites more effectively than a single effector could otherwise provide. Alternatively, pathways that degrade a metabolite of interest can be engineered into a Synthetic Biotic that also produces one or more therapeutic molecules.

2.

Synthetic Biotics Have Potential to Reduce Safety Risks by Providing Local Therapeutic Delivery

We believe that when delivered locally, Synthetic Biotics have the potential to avoid the risks often associated with systemic therapies, especially when combinations of systemic therapies are required. Our Synthetic Biotic drug candidates are orally administered, and act locally while transiting through the gut. Consequently, they decrease toxic metabolite levels in the blood to provide a systemic therapeutic benefit to the patient. Given the potential for chronic oral dosing, Synthetic Biotics may have benefits in terms of dose prediction and reversibility of activity.

3.

The Synthetic Biotic Approach is a Favorable Engine for Pharmacology

Features of our Synthetic Biotic product engine enable drug discovery and development with the potential of advancing clinical candidates more rapidly and efficiently than traditional approaches. Reasons for this include:

E. coli Nissle chassis is used across programs. Because our lead programs are based on E. coli Nissle, experience can be leveraged broadly across the portfolio to further optimize the efficiency and reproducibility of discovery, development and manufacturing efforts. The non-colonizing nature of E. coli Nissle can be combined with engineering approaches to enhance safety in terms of impact on the patient and the environment. E. coli Nissle can be engineered to require a specific exogenous nutrient supplement for growth, which limits the ability to replicate in the human body and environment. By controlling replication, we can control the number of cells being administered to a patient, which limits patient-to-patient variability. Also, dependence on an essential nutritional supplement not available in the environment reduces biocontainment risk. In addition, our chassis can be engineered to remove genes responsible for the production of the potential genotoxin colibactin, as an added safety features (Kalantari et al. Plos One 2023).

Predictive pharmacology and biomarkers. Synthetic Biotic programs are designed to achieve a target activity and support an iterative design-build-test cycle to improve performance for achieving this target. For example, Synthetic Biotic programs can be optimized by including multiple copies or regulated control of certain genes, by adding transporters for particular substrates or by optimizing enzymes for basic bacterial metabolism. These tools enable rational and iterative engineering cycles in the discovery phase.

Biomarkers as indicators of mechanistic and clinical activity may also be engineered into Synthetic Biotics to drive optimization and decision-making. By assessing the activities of our Synthetic Biotic programs using in vitro and in vivo preclinical models, we can model activity in humans. As we progress through clinical studies,

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we expect our predictive pharmacology models are further refined to inform dosing and development decisions for our additional programs.

Stability and manufacturing. Starting from known principles of manufacturing helps de-risk Synlogic’s proprietary large-scale manufacturing platform. Our lead Synthetic Biotic programs have advanced the platform by defining manufacturing processes that can be used for the entire portfolio. Our use of synthetic biology switches permits the precise control of engineered metabolic pathway activation. We use switches to suppress effector activity during manufacturing, enabling development of reproducible processes for biomass generation while maintaining robust and cost-efficient scale up of product candidates.

Manufacturing campaigns have demonstrated production reproducibility and robustness at multiple scales. The stability profile of our material has translated through the development and scale up efforts, supporting the shelf life of our strains. The implemented late stage and scale up capabilities have enabled us to produce 10,000 to 15,000 drug product doses at multiple strengths.

Collaboration Agreements

Ginkgo Bioworks, Inc.

In June 2019, we entered into an agreement with Ginkgo. The agreement provided an $80 million equity investment at a premium in Synlogic by Ginkgo and entry into a long-term strategic platform collaboration to expand and accelerate the development of Synlogic’s pipeline of Synthetic Biotics. As part of the agreement, Ginkgo purchased 422,718 shares of our common stock and accompanying Pre-Funded Warrants (the Pre-Funded Warrants) to purchase up to 169,874 shares of our common stock, at a combined price of $135.00 per share and Pre-Funded Warrant. Gross proceeds were approximately $80 million. Under the agreement, we made a prepayment to Ginkgo of $30 million for its foundry services that are being provided to us over an initial term of five years.

In February 2024, our board of directors approved the discontinuation of the Synpheny-3 trial, a significant reduction in the Company’s workforce and began evaluating strategic options for the Company. As a result of this decision, we will no longer be purchasing services from Ginkgo. During the year ended December 31, 2024, the remaining $5.2 million of prepaid expenses related to this collaboration, were recorded as restructuring and other charges on the consolidated statements of operations and comprehensive loss. Historically, the costs were recorded in current and non-current prepaid research and development, on the consolidated balance sheet. We have exclusive rights to any Synthetic Biotics that were developed as part of the collaboration and to intellectual property covering such products.

Intellectual Property and Technology Licenses

We strive to protect and enhance the proprietary technology, inventions, and improvements that are commercially important to our business, including seeking, maintaining, and defending patent rights, whether developed internally or licensed from our collaborators or other third parties. Our policy is to seek to protect our proprietary position by, among other methods, filing patent applications in the United States and in certain jurisdictions outside of the United States related to our proprietary technology, inventions, improvements, and product candidates that are important to the development and implementation of our business.

We also rely on trade secrets and know-how relating to our proprietary technology and product candidates, continuing innovation, and in-licensing opportunities to develop, strengthen, and maintain our proprietary position in the field of synthetic biology. We additionally rely on data exclusivity, market exclusivity, and patent term extensions when available, and plan to rely on additional regulatory protection afforded through orphan drug designations when applicable. Our commercial success may depend in part on our ability to obtain and maintain patent and other proprietary protection for our technology, inventions, and improvements; to preserve the confidentiality of our trade secrets; to maintain our licenses to use intellectual property owned by third parties; to defend and enforce our proprietary rights, including our patents; and to operate without infringing on the valid and enforceable patents and other proprietary rights of third parties.

We believe we are well positioned in terms of intellectual property because we:

Have built and expanded, and intend to continue expansion in, a broad worldwide portfolio of intellectual property, including patents and patent applications, in areas relevant to the development, manufacturing and formulation of human therapeutic products using live biotherapeutics based on synthetic biology; and

Intend to take additional steps, where appropriate, to further protect our intellectual property rights, including, for example, through the use of copyright and trademark protection, as well as regulatory protection available via orphan drug designations, data exclusivity, market exclusivity and patent term extensions.

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We believe our intellectual property portfolio provides broad coverage of our Synthetic Biotic platform and applicable disease-related technologies. As of February 27, 2025, we had over 112 Synlogic-owned patents and patent applications in U.S. and foreign jurisdictions, of which over 61 have been issued or allowed.

Synlogic Intellectual Property

Disease-related applications

The disease-related applications in our intellectual property portfolio relate to certain pathological conditions including, but not limited to , hyperphenylalaninemia, hyperoxaluria, homocystinuria, hyperuricemia, hyperammonemia, certain other inherited metabolic diseases and conditions, metabolic disorders, diseases and conditions associated with an inflammatory state, diseases associated with gut inflammation, compromised gut mucosal barrier (leaky gut), and various autoimmune disorders and provide coverage for engineered bacteria having genetic circuitry designed to specifically address those conditions and the associated disease states. The intellectual property portfolio provides coverage for engineered bacterial strain compositions, related formulations, methods of making the bacterial strains, methods of measuring strain activity, and methods for treating diseases. Currently, intellectual property relating to this technology includes pending applications in U.S. and foreign jurisdictions, as well as several issued U.S. patents directed to composition of matter and pharmaceutical composition claims covering our clinical candidates. The patent term for our current patents and patent applications have expiration dates ranging from December 2035 to December 2043, depending on the indication and excluding any patent term adjustments or extensions.

Platform Technology Applications

In addition to disease-specific technology, Synlogic has also developed a number of technologies broadly applicable across the Synlogic platform. We rely on a combination of patent application and trade secrets to protect our platform intellectual property. Exemplary platform technologies include our unique upstream and downstream GMP manufacturing processes, bacterial chassis-related and genetic circuitry-related technological developments, including, for example, improvements in inducible gene regulation, control of bacterial cell growth, and systems for importing metabolites, as well as systems for prevention of production of potentially genotoxic metabolites. These platform technologies, and our intellectual property coverage thereof, are broadly applicable to our therapeutic Synthetic Biotics.

General Considerations

Individual patents extend for varying periods of time, depending upon the date of filing of the patent application, the date of patent issuance, and the legal term of patents in the countries in which they are obtained. Generally, patents issued for applications filed in the United States are effective for 20 years from the earliest effective non-provisional filing date. In addition, in certain instances, a patent term can be extended to account for delays in prosecution at the U.S. Patent and Trademark Office (USPTO) and/or to recapture a portion of the term effectively lost as a result of the FDA regulatory review period. For regulatory delays, the restoration period cannot be longer than five years and the total patent term, including the restoration period, must not exceed 14 years following FDA approval. The duration of patents outside of the United States varies in accordance with provisions of applicable local law, but typically is also 20 years from the earliest effective non-provisional filing date. However, the actual protection afforded by a patent varies on a product-by-product basis, from country-to-country, and depends upon many factors, including the type of patent, the scope of its coverage, the availability of regulatory-related extensions, the availability of legal remedies in a particular country, and the validity and enforceability of the patent.

The patent positions of companies like us are generally uncertain and involve complex legal and factual questions. No consistent policy regarding the scope of claims allowable in patents in the field of synthetic biology has emerged in the United States. The patent situation outside of the United States is even more uncertain. With respect to both licensed and company-owned intellectual property, we cannot be sure that patents will be granted with respect to any of our pending patent applications or with respect to any patent applications filed by us in the future, nor can we be sure that any of our existing patents or any patents that may be granted to us the future will be commercially useful in protecting our products and the methods used to manufacture those products. For additional risks, please see the section entitled “Risk Factors—Risks Related to Intellectual Property.”

Trademarks

Our registered trademark portfolio currently contains over 40 registered or allowed trademarks.

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Other

Generally, we seek to protect our technology and product candidates, in part, by entering into confidentiality agreements with those who have access to our confidential information, including employees, contractors, consultants, collaborators, and advisors. In some circumstances, we may rely on trade secrets to protect our technology. We seek to preserve the integrity and confidentiality of our proprietary technology, trade secrets and processes by maintaining physical security of our premises and physical and electronic security of our information technology systems. Although we have confidence in these individuals, organizations, and systems, agreements or security measures may be breached and we may not have adequate remedies for any breach. In addition, our trade secrets may otherwise become known or may be independently discovered by competitors. To the extent that company employees, contractors, consultants, collaborators, and advisors use intellectual property owned by others in their work for us, disputes may arise as to the rights in related or resulting know-how and inventions. For this and more comprehensive risks related to our proprietary technology, inventions, improvements and products, please see the section entitled “Risk Factors—Risks Related to Intellectual Property.”

Regulatory Matters

Government Regulation and Product Approval

Government authorities in the United States, at the federal, state and local level, and other countries extensively regulate, among other things, the research, development, testing, manufacture, quality control, approval, labeling, packaging, storage, record keeping, promotion, advertising, distribution, marketing and export and import of products such as those we are developing. A new drug must be approved by the FDA through the New Drug Application (NDA) process and a new biologic must be approved by the FDA through the Biologics License Application (BLA), process before such products may be legally marketed in the United States.

U.S. Drug Development Process

In the United States, the FDA regulates drugs and biologics under the Federal Food, Drug, and Cosmetic Act (FDCA) and in the case of biologics, also under the Public Health Service Act (PHSA) and implementing regulations. Our product candidates will be regulated by the FDA as biologics. The process of obtaining regulatory approvals and the subsequent compliance with applicable federal, state, local, and foreign statutes and regulations require the expenditure of substantial time and financial resources. Failure to comply with the applicable U.S. requirements at any time during the product development process, approval process or after approval, may subject an applicant to administrative or judicial sanctions. These sanctions could include the FDA’s refusal to approve pending applications, withdrawal of an approval, license revocation, a clinical hold, warning letters, product recalls, product seizures, total or partial suspension of production or distribution, injunctions, fines, refusals of government contracts, restitution, disgorgement, or civil or criminal penalties. Any agency or judicial enforcement action could have a material adverse effect on us. The process required by the FDA before a biologic may be marketed in the United States generally involves the following:

Completion of required preclinical (or nonclinical) laboratory tests, animal studies and formulation studies performed in accordance with Good Laboratory Practice (GLP) and other applicable regulations;

Submission to the FDA of an investigational new drug application (IND) which must become effective before shipment of investigational product for human clinical trials may begin;

Approval by an independent institutional review board (IRB) or ethics committee at each clinical trial site before each clinical trial may be initiated;

Performance of adequate and well-controlled human clinical trials performed in accordance with applicable IND regulations, Good Clinical Practice (GCP), and other clinical-trial related regulations to evaluate the safety and efficacy of the investigational product for each proposed indication;

Good Manufacturing Practice (GMP) to prepare a drug substance and drug product analyzed using validated analytical methods;

Development and approval of a companion diagnostic device, if the FDA or the sponsor believes that its use is essential for the safe and effective use of a corresponding product;

Submission to the FDA of a BLA for marketing approval, including payment of application user fees;

Satisfactory completion of an FDA inspection of the manufacturing facility or facilities at which the biologic is produced to assess compliance with current Good Manufacturing Practice (cGMP) regulations to assure that the facilities, methods and controls are adequate to preserve the product’s identity, strength, quality and purity;

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Potential FDA audit of the clinical trial sites to assure compliance with GCP and the integrity of the clinical data submitted in support of the BLA; and

FDA review and approval of the BLA, including satisfactory completion of an FDA advisory committee review of the product candidate, where appropriate or if applicable, prior to any commercial marketing or sale of the product in the United States.

Once a pharmaceutical candidate is identified for development, it enters the preclinical testing stage. Preclinical tests include laboratory evaluations of product chemistry and formulation, animal toxicity and pharmacology studies to assess the potential for adverse events and in some cases to establish a rationale for therapeutic use. The Consolidated Appropriations Act for 2023, signed into law on December 29, 2022, (P.L. 117-328) amended the FDCA and the Public Health Service Act to specify that nonclinical testing for drugs and biologics may, but is not required to, include in vivo animal testing. According to the amended language, a sponsor may fulfill nonclinical testing requirements by completing various in vitro assays (e.g., cell-based assays, organ chips, or microphysiological systems), in silico studies (i.e., computer modeling), other human or nonhuman biology-based tests (e.g., bioprinting), or in vivo animal tests. The conduct of preclinical studies is subject to federal regulations and requirements, including GLP regulations for safety/toxicology studies.

An IND sponsor must submit the results of the preclinical tests, together with manufacturing information and analytical data, to the FDA as part of the IND. In June 2016, the FDA issued an updated guidance for the industry entitled “Early Clinical Trials with Live Biotherapeutic Products: Chemistry, Manufacturing and Control Information,” which included recommendations from the FDA regarding the chemistry, manufacturing and control information that should be included in an IND for early clinical trials with live biotherapeutic products. This guidance reflects the FDA’s thinking on the topic at the time the guidance was issued and although it is not binding on the FDA or a sponsor, it provided us with additional information about what should be included in INDs for our Synthetic Biotic product candidates. The sponsor will also include in the IND a protocol detailing, among other things, the objectives of the clinical trial, the parameters to be used in monitoring safety, and the effectiveness criteria to be evaluated, if a first phase study lends itself to an efficacy evaluation. Some long-term preclinical testing, such as animal tests of reproductive adverse events and carcinogenicity, may continue after an IND for an investigational product candidate is submitted to the FDA and human clinical trials have been initiated. The IND automatically becomes effective 30 days after receipt by the FDA, unless the FDA, within the 30-day time period, places the clinical trial on a clinical hold. In such a case, the IND sponsor and the FDA must resolve any outstanding concerns before the clinical trial can begin. Clinical holds also may be imposed by the FDA at any time before or during clinical trials due to safety concerns about ongoing or proposed clinical trials or non-compliance with specific FDA requirements, and the trials may not begin or continue until the FDA notifies the sponsor that the hold has been lifted.

All clinical trials must be conducted under the supervision of one or more qualified investigators, and in accordance with GCP requirements. They must be conducted under protocols detailing the objectives of the trial, dosing procedures, subject selection and exclusion criteria and the safety and effectiveness criteria to be evaluated. Each protocol must be submitted to the FDA as part of the IND, and timely safety reports must be submitted to the FDA and the investigators for serious and unexpected adverse events. An IRB at each institution participating in the clinical trial must review and approve each protocol before a clinical trial commences at that institution and must also approve the information regarding the trial and the consent form that must be provided to each trial subject or his or her legal representative, monitor the study until completed and otherwise comply with IRB rules and regulations. Study subjects must sign the IRB-approved informed consent form in order to participate in the clinical trial.

In addition, an IRB representing each institution that is participating in the clinical trial must review and approve the plan for any clinical trial before it commences at that institution, and the IRB must conduct a continuing review and reapprove the trial at least annually. The IRB must review and approve, among other things, the trial protocol and informed consent information to be provided to clinical trial subjects. An IRB must operate in compliance with FDA regulations.

Human clinical trials are typically conducted in three sequential phases that may overlap or be combined:

Phase 1: The product candidate is initially introduced into healthy human subjects and tested for safety, dosage tolerance, absorption, metabolism, distribution and excretion. In the case of some products for severe or life-threatening diseases, such as cancer, especially when the product candidate may be too inherently toxic to ethically administer to healthy volunteers, the initial human testing is usually conducted in patients.

Phase 2: This phase involves clinical trials in a limited patient population to identify possible adverse effects and safety risks, to preliminarily evaluate the efficacy of the product candidate for specific targeted diseases and to determine dosage tolerance and optimal dosage.

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Phase 3: Larger clinical trials are undertaken to further evaluate dosage, clinical efficacy and safety in an expanded patient population, often at geographically dispersed clinical study sites. These clinical trials are intended to establish the overall risk: benefit ratio of the product candidate and provide, if appropriate, an adequate basis for product labeling. These trials may include comparisons with placebo and/or other comparator treatments. The duration of treatment is often extended to mimic the actual use of a product during marketing.

Post-approval trials, sometimes referred to as Phase 4, may be conducted after initial marketing approval. These trials are used to gain additional experience from the treatment of patients in the intended therapeutic indication. In certain instances, the FDA may mandate the performance of Phase 4 clinical trials as a condition of approval of a BLA.

In the Consolidated Appropriations Act for 2023, Congress amended the FDCA to require sponsors of a Phase 3 clinical trial, or other “pivotal study” of a new drug to support marketing authorization, to submit a diversity action plan for such clinical trial. The action plan must include the sponsor’s diversity goals for enrollment, as well as a rationale for the goals and a description of how the sponsor will meet them. A sponsor must submit a diversity action plan to FDA by the time the sponsor submits the trial protocol to the agency for review. The FDA may grant a waiver for some or all of the requirements for a diversity action plan. It is unknown at this time how the diversity action plan may affect Phase 3 trial planning and timing or what specific information FDA will expect in such plans, but if FDA objects to a sponsor’s diversity action plan and requires the sponsor to amend the plan or take other actions, it may delay trial initiation.

The FDA or the sponsor may suspend or terminate a clinical trial at any time on various grounds, including a finding that the research subjects or patients are being exposed to an unacceptable health risk. Similarly, an IRB can suspend or terminate approval of a clinical trial at its institution if the clinical trial is not being conducted in accordance with the clinical protocol, cGMP or IRB requirements or if the product candidate has been associated with unexpected serious harm to patients. Additionally, some clinical trials are overseen by an independent group of qualified experts organized by the sponsor, known as a data safety monitoring board or committee. Depending on its charter, this group may determine whether a trial may move forward at designated check points based on access to certain data from the trial. Phase 1, Phase 2, and Phase 3 clinical testing may not be completed successfully within any specified period, if at all.

During the development of a new biologic, sponsors have the opportunity to meet with the FDA at certain points. These points may be prior to submission of an IND, at the end of Phase 2, and before a BLA is submitted. Meetings at other times may be requested. These meetings can provide an opportunity for the sponsor to share information about the data gathered to date, for the FDA to provide advice, and for the sponsor and the FDA to reach agreement on the next phase of development. Sponsors typically use the end of Phase 2 meeting to discuss their Phase 2 clinical results with the FDA and to present their plans for the pivotal Phase 3 clinical trial that they believe will support approval of the investigational biologic. If this type of discussion occurs, a sponsor may be able to request a Special Protocol Assessment (SPA), the purpose of which is to reach agreement with the FDA on the design of the Phase 3 clinical trial protocol design and analysis that will form the primary basis of an efficacy claim.

Concurrent with clinical trials, companies usually complete the additional animal studies that may be required for approval and must also develop additional information about the chemistry and physical characteristics of the biologic and finalize a process for manufacturing the product in commercial quantities in accordance with cGMP requirements. The manufacturing process must be capable of consistently producing acceptable quality batches of the product candidate and, among other things the manufacturer must develop methods for testing the identity, strength, quality and purity of the final product. Additionally, appropriate packaging must be selected and tested and stability studies must be conducted to demonstrate that the product candidate does not undergo unacceptable deterioration over its shelf life.

While the IND is active and before approval, progress reports must be submitted at least annually to the FDA, and written IND safety reports must be submitted to the FDA and investigators for serious and unexpected suspected adverse reactions, findings from other studies suggesting a significant risk to humans exposed to the same or similar drugs, findings from animal or in vitro testing suggesting a significant risk to humans, and any clinically important increased incidence of a serious suspected adverse reaction compared to that listed in the protocol or investigator brochure. The annual report is customarily submitted in the form of a Development Safety Update Report (DSUR) which is accepted as being equivalent to an IND Annual Report and also meets requirements of the EU (European Union) and International Conference on Harmonization (ICH).

There are also requirements governing the reporting of ongoing clinical trials and completed trial results to public registries. Sponsors of most clinical trials of FDA-regulated products are required to register and disclose specified clinical trial information, which is publicly available at ClinicalTrials.gov. Information related to the product, patient population, phase of investigation, trial sites and investigators and other aspects of the clinical trial is then made public as part of the registration. Sponsors are also obligated to submit the results of their clinical trials after completion, but disclosure of the results can be delayed in some cases for up to two

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years after the date of completion of the trial. Competitors may use this publicly available information to gain knowledge regarding the progress of development programs. Failure to timely register a covered clinical study or to submit study results as provided for in the law can give rise to civil monetary penalties and also prevent the non-compliant party from receiving future grant funds from the federal government. The NIH’s Final Rule on ClinicalTrials.gov registration and reporting requirements became effective in 2017, and both NIH and FDA recently began enforcing those requirements against non-compliant clinical trial sponsors.

U.S. Review and Approval Processes

Assuming successful completion of the required clinical testing, the results of the nonclinical studies and clinical trials, along with detailed information relating to the product’s chemistry, manufacturing, and controls, stability, quality control and product release procedures, proposed labeling, and other relevant information are submitted to the FDA as part of a BLA, requesting approval to market the product for one or more indications. The submission of a BLA is subject to the payment of a significant user fee (for example, for FY2024 this application fee exceeds $4 million); although a waiver of such fee may be obtained under certain limited circumstances, including where the biologic has been designated as an orphan drug. The sponsor of an approved BLA is also subject to an annual program fee, currently more than $415,000 per program. These fees are typically increased annually, but exemptions and waivers may be available under certain circumstances (such as a waiver for the first human drug application submitted by a qualifying small business and exemptions for orphan products).

The FDA reviews all BLAs submitted to ensure that they are sufficiently complete for substantive review before it accepts them for filing. The FDA may request additional information rather than accept a BLA for filing. In this event, the BLA must be resubmitted with the additional information. The resubmitted application also is subject to review before the FDA accepts it for filing. Once the submission is accepted for filing, the FDA begins an in-depth substantive review. Under the goals and policies agreed to by the FDA under the Prescription Drug User Fee Act, or PDUFA, for original BLAs, the FDA has ten months from the filing date in which to complete its initial review of a standard application and respond to the applicant, and six months from the filing date for an application with priority review. The FDA does not always meet its PDUFA goal dates, and the review process is often significantly extended by FDA requests for additional information or clarification and a sponsor’s process to respond to such inquiries. Specifically, the review process may be extended by the FDA for three additional months to consider new information or in the case of a clarification provided by the applicant to address an outstanding deficiency identified by the FDA following the original submission.

Before approving a BLA, the FDA will typically conduct a pre-approval inspection of the manufacturing facilities for the new product to determine whether the manufacturing processes and facilities comply with cGMPs. The FDA will not approve the product unless it determines that the manufacturing processes and facilities are in compliance with cGMP requirements and adequate to assure consistent production of the product within required specifications. These pre-approval inspections may cover all facilities associated with the BLA submission, including component manufacturing, finished product manufacturing, and control testing laboratories. The FDA also may inspect the sponsor and one or more clinical trial sites to assure compliance with GCP requirements and the integrity of the clinical data submitted to the FDA. If the FDA determines the application, manufacturing process or manufacturing facilities are not acceptable, it typically will outline the deficiencies and often will request additional testing or information. This may significantly delay further review of the application. If the FDA finds that a clinical site did not conduct the clinical trial in accordance with GCP, the FDA may, for example, determine the data generated by the clinical site should be excluded from the primary efficacy analyses provided in the BLA.

The FDA may refer any BLA including applications for novel biologic candidates which present difficult questions of safety or efficacy, to an advisory committee for review, evaluation and recommendation as to whether the application should be approved and under what conditions. Typically, an advisory committee is a panel of independent experts, including clinicians and other scientific experts, that reviews, evaluates and provides a recommendation as to whether the application should be approved and, if so, under what conditions. The FDA is not bound by the recommendation of an advisory committee, but it considers such recommendations when making final decisions on approval.

The approval process is lengthy and often difficult, and the FDA may refuse to approve a BLA if the applicable regulatory criteria are not satisfied or may require additional clinical or other data and information. Even if such data and information are submitted, the FDA may ultimately decide that the BLA does not satisfy the criteria for approval. Data obtained from clinical trials are not always conclusive and the FDA may interpret data differently than we interpret the same data. After the FDA evaluates a BLA, it will issue an approval letter or a Complete Response Letter (CRL). An approval letter authorizes commercial marketing of the drug with prescribing information for specific indications. A CRL indicates that the review cycle of the application is complete and the application will not be approved in its present form. A CRL usually describes the specific deficiencies in the BLA identified by the FDA and may require additional clinical data, such as an additional pivotal Phase 3 trial or other significant and time-consuming requirements related to clinical trials, nonclinical studies or manufacturing. If a CRL is issued, the sponsor must resubmit the BLA, addressing all of the deficiencies identified in the letter, or withdraw the application. Even if such data and information are submitted,

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the FDA may decide that the BLA does not satisfy the criteria for approval. The FDA reviews a BLA to determine, among other things, whether the product is safe, pure, potent and effective and the facility in which it is manufactured, processed, packed or held meets standards designed to assure the product’s continued identity, strength, quality, potency and purity.

If a product receives regulatory approval, the approval is limited to the conditions of use (e.g., patient population, indication) described in the BLA, which could restrict the commercial value of the product. Further, depending on the specific risk(s) to be addressed, the FDA may require that contraindications, warnings or precautions be included in the product labeling, require a sponsor to conduct Phase 4 testing which involves clinical trials designed to further assess a drug’s safety and effectiveness after BLA approval and may require testing and surveillance programs to monitor the safety of approved products which have been commercialized. The FDA may also place other conditions on approval including the requirement for a REMS (Risk Evaluation and Mitigation Strategies), to assure the safe use of the drug. If the FDA concludes a REMS is needed, the sponsor of the BLA must submit a proposed REMS. The FDA will not approve the BLA without an approved REMS, if required. A REMS could include medication guides, physician communication plans or elements to assure safe use, such as restricted distribution methods, patient registries and other risk minimization tools. Any of these limitations on approval or marketing could restrict the commercial promotion, distribution, prescription or dispensing of products. Marketing approval may be withdrawn for non-compliance with regulatory requirements or if problems occur following initial marketing.

Under the Pediatric Research Equity Act (PREA), as amended, an initial BLA or certain supplements to a BLA for a novel product must contain data to assess the safety and effectiveness of the product candidate for the claimed indications in all relevant pediatric subpopulations and to support dosing and administration for each pediatric subpopulation for which the product is safe and effective. The FDA may, on its own initiative or at the request of the applicant, grant deferrals for submission of pediatric data until after approval of the product for use in adults or full or partial waivers from the pediatric data requirement. Unless otherwise required by regulation, PREA does not typically apply to any therapeutic product for an indication for which orphan designation has been granted. The Food and Drug Administration Safety and Innovation Act (FDASIA), enacted in 2012, made permanent the PREA requirement that a sponsor who is planning to submit a marketing application for a product that includes a new active ingredient, new indication, new dosage form, new dosing regimen or new route of administration must submit an initial Pediatric Study Plan (PSP), within sixty days of an end-of-Phase 2 meeting or, if there is no such meeting, as early as practicable before the initiation of the Phase 3 or Phase 2/3 clinical trial. The initial PSP must include an outline of the pediatric study or studies that the sponsor plans to conduct, including trial objectives and design, age groups, relevant endpoints and statistical approach, or a justification for not including such detailed information, and any request for a deferral of pediatric assessments or a full or partial waiver of the requirement to provide data from pediatric studies along with supporting information. The FDA and the sponsor must reach an agreement on the PSP. A sponsor can submit amendments to an agreed upon initial PSP at any time if changes to the pediatric plan need to be considered based on data collected from pre-clinical studies, early phase clinical trials or other clinical development programs.

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Patent Term Restoration and Marketing Exclusivity

Depending upon the timing, duration and specifics of FDA approval of our drugs, some of our U.S. patents may be eligible for limited patent term extension under the Drug Price Competition and Patent Term Restoration Act of 1984 (referred to as the Hatch Waxman Amendments). The Hatch Waxman Amendments permit a patent restoration term of up to five years as compensation for patent term lost during product development and the FDA regulatory review process. However, patent term restoration cannot extend the remaining term of a patent beyond a total of 14 years from the product’s approval date. The patent term restoration period is generally one half the time between the effective date of an IND, and the submission date of a BLA, plus the time between the submission date of a BLA and the approval of that application. Only one patent applicable to an approved drug is eligible for the extension, and the extension must be applied for, prior to expiration of the patent. The USPTO, in consultation with the FDA, reviews and approves the application for any patent term extension or restoration. In the future, we intend to apply for restorations of patent term for some of its currently-owned or licensed patents to add patent life beyond their current expiration date, depending on the expected length of clinical trials and other factors involved in the filing of the relevant BLA.

Pediatric exclusivity is a type of non-patent marketing exclusivity available in the United States, and, if granted, it provides for the attachment of an additional six months of marketing protection to the term of any existing regulatory exclusivity or listed patents. This six-month exclusivity may be granted if an NDA/BLA sponsor submits clinical pediatric data that fairly respond to a written request from the FDA for such data. The data do not need to show the product to be effective in the pediatric population studied; rather, if the clinical trial is deemed to fairly respond to the FDA’s request, the additional protection is granted. If reports of requested pediatric studies are submitted to and accepted by the FDA within the statutory time limits, whatever statutory or regulatory periods of exclusivity or patent protection cover the product are extended by six months. This is not a patent term extension, but it effectively extends the regulatory period during which the FDA cannot approve another application for the same drug/biologic. The issuance of a written request does not require the sponsor to undertake the described clinical trials. To date, we have not received or requested any FDA written requests.

Biologics Price Competition and Innovation Act of 2009

The Patient Protection and Affordable Care Act, as amended by the Health Care and Education Affordability Reconciliation Act of 2010 (collectively, ACA), which included the Biologics Price Competition and Innovation Act (BPCIA), amended the PHSA to create an abbreviated approval pathway for biological products that are biosimilar to or interchangeable with an FDA-licensed reference biological product. A biosimilar product is defined as one that is highly similar to a reference product notwithstanding minor differences in clinically-inactive components and for which there are no clinically meaningful differences between the biological product and the reference product in terms of the safety, purity and potency of the product. An interchangeable product is a biosimilar product that can be expected to produce the same clinical results as the reference product in any given patient and, for products administered multiple times to an individual, that the product and the reference product may be alternated or switched after one has been previously administered without increasing safety risks or risks of diminished efficacy relative to exclusive use of the reference biological product without such alternation or switch. Upon licensure by the FDA, an interchangeable biosimilar may be substituted for the reference product without the intervention of the health care provider who prescribed the reference product.

Under the BPCIA, a manufacturer may submit an abbreviated application for licensure of a biologic that is biosimilar to or interchangeable with an FDA-licensed reference biological product. This abbreviated approval pathway is intended to permit a biosimilar to come to market more quickly and less expensively than if a “full” BLA were submitted, by relying to some extent on the FDA’s previous review and approval of the reference biologic to which the proposed product is similar.

Under the abbreviated approval pathway, the biosimilar applicant must demonstrate that the product is biosimilar based on data from (1) analytical studies showing that the biosimilar product is highly similar to the reference product; (2) animal studies (including toxicity); and (3) one or more clinical trials to demonstrate safety, purity and potency in one or more appropriate conditions of use for which the reference product is approved. In addition, the applicant must show that the biosimilar and reference products have the same mechanism of action for the conditions of use on the label, route of administration, dosage and strength, and the production facility must meet standards designed to assure product safety, purity and potency.

A reference biological product is granted 12 years of data exclusivity from the time of first licensure of the product, and the first approved interchangeable biologic product will be granted an exclusivity period of up to one year after it is first commercially marketed. If pediatric studies are performed and accepted by the FDA as responsive to a Written Request, the 12-year exclusivity period will be extended for an additional six months.

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In addition, the FDA will not accept an application for a biosimilar or interchangeable product based on the reference biological product until four years after the date of first licensure of the reference product. “First licensure” typically means the initial date the particular product at issue was licensed in the United States. Date of first licensure does not include the date of licensure of (and a new period of exclusivity is not available for) a supplement for the reference product for a subsequent application filed by the same sponsor or manufacturer of the reference product (or licensor, predecessor in interest or other related entity) for a change (not including a modification to the structure of the biological product) that results in a new indication, route of administration, dosing schedule, dosage form, delivery system, delivery device or strength or for a modification to the structure of the biological product that does not result in a change in safety, purity or potency. Therefore, one must determine whether a new product includes a modification to the structure of a previously licensed product that results in a change in safety, purity or potency to assess whether the licensure of the new product is a first licensure that triggers its own period of exclusivity. Whether a subsequent application, if approved, warrants exclusivity as the “first licensure” of a biological product is determined on a case-by-case basis with data submitted by the sponsor.

The BPCIA is complex and is still being interpreted and implemented by the FDA. In addition, recent government proposals have sought to reduce the 12-year reference product exclusivity period. Other aspects of the BPCIA, some of which may impact the BPCIA exclusivity provisions, have also been the subject of recent litigation. As a result, the ultimate impact, implementation and meaning of the BPCIA is subject to significant uncertainty.

To date, the FDA has approved a number of biosimilars, and numerous biosimilars have been approved in Europe. The FDA has also issued several guidance documents outlining its approach to reviewing and approving biosimilars and interchangeable biosimilars.

Orphan Drug Designation

Under the Orphan Drug Act, the FDA may grant orphan drug designation to a drug intended to treat a rare disease or condition, which is generally defined as a disease or condition that affects fewer than 200,000 individuals in the United States, or more than 200,000 individuals in the United States and for which there is no reasonable expectation that the cost of developing and making available in the United States a drug for this type of disease or condition will be recovered from sales in the United States for that drug. Orphan drug designation must be requested before submitting a BLA. After the FDA grants orphan drug designation, the identity of the therapeutic agent and its potential orphan use will be disclosed publicly by the FDA; the posting will also indicate whether a drug is no longer designated as an orphan drug. More than one product candidate may receive an orphan drug designation for the same indication. The benefits of orphan drug designation include research and development tax credits and exemption from FDA prescription drug user fees. Orphan drug designation, however, does not convey any advantage in or shorten the duration of the regulatory review and approval process.

Generally, if a product that receives orphan designation receives the first FDA approval for the orphan indication, the product is entitled to orphan drug exclusivity, which means that for seven years, the FDA is prohibited from approving any other applications to market the same drug or biological product for the same indication, except in limited circumstances described further below. Orphan exclusivity does not block the approval of a different drug or biologic for the same rare disease or condition, nor does it block the approval of the same drug or biologic for different conditions. As a result, even if one of our product candidates receive orphan exclusivity, the FDA can still approve different drugs or biologics for use in treating the same indication or disease, which could create a more competitive market for us. Additionally, if a drug or biologic designated as an orphan product receives marketing approval for an indication broader than what was designated, it may not be entitled to orphan drug exclusivity.

Orphan exclusivity will not bar approval of another product with the same drug or biologic for the same condition under certain circumstances, including if a subsequent product with the same drug or biologic for the same condition is shown to be clinically superior to the approved product on the basis of greater efficacy or safety or a major contribution to patient care, or if the company with orphan drug exclusivity cannot assure the availability of sufficient quantities of the drug or biologic to meet the needs of persons with the disease or condition for which the drug or biologic was designated. Thus, orphan drug exclusivity could also block the approval of one of our products for seven years if a competitor obtains approval of the same drug, as defined by the FDA, and we are not able to show the clinical superiority of our drug or if our product candidate is determined to be contained within the competitor’s product for the same indication or disease.

Recent court cases have challenged FDA’s approach to determining the scope of orphan drug exclusivity; however, at this time the agency continues to apply its long-standing interpretation of the governing regulations and has stated that it does not plan to change any orphan drug implementing regulations.

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In May 2023, the FDA granted labafenogene marselecobac Orphan Drug Designation. Additionally, in October 2017, the FDA granted SYNB1618 Orphan Drug designation for the treatment of PKU and in November 2022, the FDA granted SYNB1353 Orphan Drug designation for the treatment of HCU.

Fast Track, Breakthrough Therapy, Rare Pediatric Disease and Priority Review Designations

The FDA is authorized to designate certain products for expedited development or review if they are intended to address an unmet medical need in the treatment of a serious or life-threatening disease or condition. These programs include Fast Track designation, breakthrough therapy designation and priority review designation.

To be eligible for a Fast Track designation, the FDA must determine, from the request of a sponsor, based on preclinical studies, that a product is intended to treat a serious or life-threatening disease or condition and demonstrates the potential to address an unmet medical need by providing a therapy where none exists or a therapy that may be potentially superior to existing therapy based on efficacy or safety factors. Fast Track designation provides opportunities for more frequent interactions with the FDA review team to expedite development and review of the product. The FDA may also review sections of the NDA or BLA for a Fast Track product on a rolling basis before the complete application is submitted, if the sponsor and the FDA agree on a schedule for the submission of the application sections, and the sponsor pays any required user fees upon submission of the first section of the NDA or BLA. In addition, Fast Track designation may be withdrawn by the sponsor or rescinded by the FDA if the designation is no longer supported by data emerging in the clinical trial process.

In addition, with the enactment of FDASIA in 2012, Congress created a new regulatory program for product candidates designated by FDA as “breakthrough therapies” upon a request made by the IND sponsors. A breakthrough therapy is defined as a drug or biologic that is intended, alone or in combination with one or more other drugs or biologics, to treat a serious or life-threatening disease or condition, and preliminary clinical evidence indicates that the drug or biologic may demonstrate substantial improvement over existing therapies on one or more clinically significant endpoints, such as substantial treatment effects observed early in clinical development. Drugs or biologics designated as breakthrough therapies are also eligible for accelerated approval of their respective marketing applications. The FDA must take certain actions with respect to breakthrough therapies, such as holding timely meetings with and providing advice to the product sponsor, intended to expedite the development and review of an application for approval of a breakthrough therapy.

Finally, the FDA may designate a product for priority review if it is a drug or biologic that treats a serious condition and, if approved, would provide a significant improvement in safety or effectiveness. The FDA determines at the time that the marketing application is submitted, on a case- by-case basis, whether the proposed drug represents a significant improvement in treatment, prevention or diagnosis of disease when compared with other available therapies. Significant improvement may be illustrated by evidence of increased effectiveness in the treatment of a condition, elimination or substantial reduction of a treatment-limiting drug reaction, documented enhancement of patient compliance that may lead to improvement in serious outcomes, or evidence of safety and effectiveness in a new subpopulation. A priority review designation is intended to direct overall attention and resources to the evaluation of such applications, and to shorten the FDA’s goal for taking action on a marketing application from ten months to six months for an original BLA or for an NDA for a new molecular entity from the date of filing.

Finally, the FDA may designate a product for priority review if it is a drug or biologic that treats a serious condition and, if approved, would provide a significant improvement in safety or effectiveness. The FDA determines at the time that the marketing application is submitted, on a case- by-case basis, whether the proposed drug represents a significant improvement in treatment, prevention or diagnosis of disease when compared with other available therapies. Significant improvement may be illustrated by evidence of increased effectiveness in the treatment of a condition, elimination or substantial reduction of a treatment-limiting drug reaction, documented enhancement of patient compliance that may lead to improvement in serious outcomes, or evidence of safety and effectiveness in a new subpopulation. A priority review designation is intended to direct overall attention and resources to the evaluation of such applications, and to shorten the FDA’s goal for taking action on a marketing application from ten months to six months for an original BLA or for an NDA for a new molecular entity from the date of filing.

The FDA grants Rare Pediatric Disease Designation (RPDD) for serious and life-threatening diseases that primarily affect individuals from birth to 18 years old and fewer than 200,000 persons in the U.S. Under this program, a sponsor who receives an approval for a drug or biologic for a “rare pediatric disease” designation may qualify for a pediatric priority review voucher (pPRV) that can be redeemed to receive a priority review of a subsequent marketing application for a different product. The Rare Pediatric Disease Priority Review Voucher program was reauthorized in the Creating Hope Reauthorization Act in December 2020, allowing a product that is designated as a product for a rare pediatric disease prior to October 1, 2024 to be eligible to receive a Priority Review Voucher upon approval of a qualifying NDA or BLA prior to October 1, 2026.

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Even if a product qualifies for one or more of these programs, the FDA may later decide that the product no longer meets the conditions for qualification or decide that the time period for FDA review or approval will not be shortened. Furthermore, Fast Track designation, breakthrough therapy designation and priority review do not change the standards for approval and may not ultimately expedite the development or approval process.

In July 2023, the FDA granted Fast Track designation for the use of labafenogene marselecobac for the treatment of PKU. In addition, in April 2018, the FDA granted Fast Track designation for the use of SYNB1618 for the treatment of PKU. In August 2022, the FDA granted Fast Track designation for the use of SYNB1353 for the treatment of HCU. In January of 2023, Synlogic announced the FDA’s granting of RPDD for SYNB1353 for HCU and for SYNB1934 for PKU.

Accelerated Approval Pathway

In addition, products studied for their safety and effectiveness in treating serious or life-threatening illnesses and that provide meaningful therapeutic benefit over existing treatments may receive accelerated approval from the FDA and may be approved on the basis of adequate and well-controlled clinical trials establishing that the drug product has an effect on a surrogate endpoint that is reasonably likely to predict clinical benefit. The FDA may also grant accelerated approval for such a drug or biologic when the product has an effect on an intermediate clinical endpoint that can be measured earlier than an effect on irreversible morbidity or mortality, or IMM, and that is reasonably likely to predict an effect on IMM or other clinical benefit, taking into account the severity, rarity, or prevalence of the condition and the availability or lack of alternative treatments. As a condition of approval, the FDA may require that a sponsor of a drug receiving accelerated approval perform post-marketing clinical trials to verify and describe the predicted effect on IMM or other clinical endpoint, and the product may be subject to expedited withdrawal procedures. Drugs and biologics granted accelerated approval must meet the same statutory standards for safety and effectiveness as those granted traditional approval.

For the purposes of accelerated approval, a surrogate endpoint is a marker, such as a laboratory measurement, radiographic image, physical sign, or other measure that is thought to predict clinical benefit but is not itself a measure of clinical benefit. Surrogate endpoints can often be measured more easily or more rapidly than clinical endpoints. An intermediate clinical endpoint is a measurement of a therapeutic effect that is considered reasonably likely to predict the clinical benefit of a drug, such as an effect on IMM. The FDA has limited experience with accelerated approvals based on intermediate clinical endpoints but has indicated that such endpoints generally may support accelerated approval when the therapeutic effect measured by the endpoint is not itself a clinical benefit and basis for traditional approval, if there is a basis for concluding that the therapeutic effect is reasonably likely to predict the ultimate long-term clinical benefit of a drug.

The accelerated approval pathway is most often used in settings in which the course of a disease is long and an extended period of time is required to measure the intended clinical benefit of a drug, even if the effect on the surrogate or intermediate clinical endpoint occurs rapidly. For example, accelerated approval has been used extensively in the development and approval of drugs for treatment of a variety of cancers in which the goal of therapy is generally to improve survival or decrease morbidity and the duration of the typical disease course requires lengthy and sometimes large clinical trials to demonstrate a clinical or survival benefit.

The accelerated approval pathway is usually contingent on a sponsor’s agreement to conduct, in a diligent manner, additional post-approval confirmatory studies to verify and describe the drug’s clinical benefit. As a result, a product candidate approved on this basis is subject to rigorous post-marketing compliance requirements, including the completion of Phase 4 or post-approval clinical trials to confirm the effect on the clinical endpoint. Failure to conduct required post-approval studies, or to confirm the predicted clinical benefit of the product during post-marketing studies, would allow the FDA to withdraw approval of the drug. All promotional materials for product candidates being considered and approved under the accelerated approval program are subject to prior review by the FDA.

As part of the Consolidated Appropriations Act for 2023, Congress provided FDA additional statutory authority to mitigate potential risks to patients from continued marketing of ineffective drugs previously granted accelerated approval. Under the Act’s amendments to the FDCA, FDA may require the sponsor of a product granted accelerated approval to have a confirmatory trial underway prior to approval. The sponsor must also submit progress reports on a confirmatory trial every six months until the trial is complete, and such reports are published on FDA’s website. The amendments also give FDA the option of using expedited procedures to withdraw product approval if the sponsor’s confirmatory trial fails to verify the claimed clinical benefits of the product.

Post-Approval Requirements

Following approval of a new product, the manufacturer and the approved product are subject to pervasive and continuing regulation by the FDA, including, among other things, monitoring and recordkeeping activities, reporting of adverse experiences with

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the product, product sampling and distribution restrictions, complying with promotion and advertising requirements, which include restrictions on promoting biologics for unapproved uses or patient populations (i.e., “off-label use”) and limitations on industry-sponsored scientific and educational activities. Although physicians may prescribe legally available products for off-label uses, manufacturers may not market or promote such uses. The FDA and other agencies actively enforce the laws and regulations prohibiting the promotion of off-label uses, and a company that is found to have improperly promoted off-label uses may be subject to significant liability. If there are any modifications to the product, including changes in indications, labeling or manufacturing processes or facilities, the applicant may be required to submit and obtain FDA approval of a new BLA or a BLA supplement, which may require the applicant to develop additional data or conduct additional pre-clinical studies and clinical trials. The FDA may also place other conditions on approvals including the requirement for a REMS to assure the safe use of the product. A REMS could include medication guides, physician communication plans or elements to assure safe use, such as restricted distribution methods, patient registries and other risk minimization tools. Any of these limitations on approval or marketing could restrict the commercial promotion, distribution, prescription or dispensing of products. Product approvals may be withdrawn for non-compliance with regulatory standards or if problems occur following initial marketing.

FDA regulations require that products be manufactured in specific approved facilities and in accordance with cGMPs. The cGMP regulations include requirements relating to organization of personnel, buildings and facilities, equipment, control of components and finished product containers and closures, production and process controls, packaging and labeling controls, holding and distribution, laboratory controls, records and reports and returned or salvaged products. The manufacturing facilities for our product candidates must meet cGMP requirements and satisfy the FDA or comparable foreign regulatory authorities before any product is approved and our commercial products can be manufactured. We rely, and expect to continue to rely, on third parties for the production of clinical and commercial quantities of our products in accordance with cGMP regulations. These manufacturers must comply with cGMP regulations that require, among other things, quality control and quality assurance, the maintenance of records and documentation and the obligation to investigate and correct any deviations from cGMP. Manufacturers and other entities involved in the manufacture and distribution of approved drugs or biologics are required to register their establishments with the FDA and certain state agencies and are subject to periodic prescheduled or unannounced inspections by the FDA and certain state agencies for compliance with cGMP and other laws. Accordingly, manufacturers must continue to expend time, money and effort in the area of production and quality control to maintain cGMP compliance. Future inspections by the FDA and other regulatory agencies may identify compliance issues at the facilities of our CMOs that may disrupt production or distribution or require substantial resources to correct. In addition, the discovery of conditions that violate these rules, including failure to conform to cGMPs, could result in enforcement actions, and the discovery of problems with a product after approval may result in restrictions on a product, manufacturer or holder of an approved BLA, including voluntary recall and regulatory sanctions as described below.

Once an approval is granted, the FDA may withdraw the approval if compliance with regulatory standards is not maintained or if problems occur or are discovered after the product reaches the market. Later discovery of previously unknown problems with a product may result in mandatory revisions to the approved labeling to add new safety information; imposition of post-market or clinical trials to assess new safety risks; or imposition of distribution or other restrictions under a REMS program. Other potential consequences include, among other things:

Restrictions on the marketing or manufacturing of the product, complete withdrawal of the product from the market or product recalls;

Fines, warning letters or other enforcement-related letters or clinical holds on post-approval clinical trials;

Refusal of the FDA to approve pending NDAs/BLAs or supplements to approved NDAs/BLAs, or suspension or revocation of product approvals;

Product seizure or detention, or refusal to permit the import or export of products;

Injunctions or the imposition of civil or criminal penalties; and

Consent decrees, corporate integrity agreements, debarment, or exclusion from federal health care programs; or mandated modification of promotional materials and labeling and the issuance of corrective information.

In addition, the distribution of prescription pharmaceutical products is subject to the Prescription Drug Marketing Act, or PDMA, which regulates the distribution of drugs and drug samples at the federal level and sets minimum standards for the registration and regulation of drug distributors by the states. Both the PDMA and state laws limit the distribution of prescription pharmaceutical product samples and impose requirements to ensure accountability in distribution. Most recently, the Drug Supply Chain Security Act, or DSCSA, was enacted with the aim of building an electronic system to identify and trace certain prescription drugs distributed in the United States, including most biological products. The DSCSA mandates phased-in and resource-intensive obligations for pharmaceutical manufacturers, wholesale distributors, and dispensers over a ten-year period, which culminated in November 2023.

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Most recently, the FDA announced a one-year stabilization period to November 2024, giving entities subject to the DSCSA additional time to finalize interoperable tracking systems and to ensure supply chain continuity.

From time to time, new legislation is drafted, introduced and passed in Congress that could significantly change the statutory provisions governing the approval, manufacturing and marketing of products regulated by the FDA. It is impossible to predict whether further legislative changes will be enacted, or FDA regulations, guidance or interpretations will be changed or what the impact of such changes, if any, may be.

Foreign Regulation

In addition to regulations in the United States, we will be subject to a variety of foreign regulations governing the performance of clinical trials outside the United States and commercial sales and distribution of our products outside of the United States. Whether or not we obtain FDA approval for a product candidate, we must obtain approval by the comparable regulatory authorities of foreign countries or economic areas, such as the European Union, before we may commence clinical trials or market products in those countries or areas. The approval process and requirements governing the conduct of clinical trials, product licensing, pricing and reimbursement vary greatly between countries and jurisdictions and can involve additional testing and additional administrative review periods. The time required to obtain approval in other countries and jurisdictions might differ from and be longer than that required to obtain FDA approval. Regulatory approval in one country or jurisdiction does not ensure regulatory approval in another, but a failure or delay in obtaining regulatory approval in one country or jurisdiction may negatively impact the regulatory process in others.

European Union drug development, review and approval

In the European Union, our product candidates also may be subject to extensive regulatory requirements. As in the United States, medicinal products can be marketed only if a marketing authorization from the competent regulatory agencies has been obtained. Similar to the United States, the various phases of pre-clinical and clinical research in the European Union are subject to significant regulatory controls.

The new Clinical Trials Regulation, (EU) No 536/2014, which took effect on January 31, 2022, aims to simplify and streamline the approval of clinical trials in the European Union. The main characteristics of the regulation include: a streamlined application procedure via a single entry point, the “EU clinical trial portal and database”; a single set of documents to be prepared and submitted for the application as well as simplified reporting procedures for clinical trial sponsors; and a harmonized procedure for the assessment of applications for clinical trials, which is divided in two parts. Part I is assessed by the appointed reporting member state, whose assessment report is submitted for review by the sponsor and all other competent authorities of all European Union member states in which an application for authorization of a clinical trial has been submitted (Concerned Member States). Part II is assessed separately by each Concerned Member State. Strict deadlines have been established for the assessment of clinical trial applications. The role of the relevant ethics committees in the assessment procedure will continue to be governed by the national law of the Concerned Member State. However, overall related timelines will be defined by the Clinical Trials Regulation.

As in the United States, similar requirements for posting clinical trial information are described in the European Union (EudraCT) website: https://eudract.ema.europa.eu.

To obtain a marketing authorization of a drug in the European Union, we may submit marketing authorization applications, or MAA, either under the so-called centralized or national authorization procedures.

Centralized procedure

The centralized procedure provides for the grant of a single marketing authorization following a favorable opinion by the European Medicines Agency (the EMA) that is valid in all EU member states, as well as Iceland, Liechtenstein and Norway. The centralized procedure is compulsory for medicines produced by specified biotechnological processes, products designated as orphan medicinal products, advanced-therapy medicines (such as gene-therapy, somatic cell-therapy or tissue-engineered medicines) and products with a new active substance indicated for the treatment of specified diseases, such as HIV/AIDS, cancer, diabetes, neurodegenerative disorders or autoimmune diseases and other immune dysfunctions and viral diseases. The centralized procedure is optional for products that represent a significant therapeutic, scientific or technical innovation, or whose authorization would be in the interest of public health. Under the centralized procedure the maximum timeframe for the evaluation of an MAA by the EMA is 210 days, excluding clock stops, when additional written or oral information is to be provided by the applicant in response to questions asked by the Committee for Medicinal Products for Human Use, or the CHMP. Accelerated assessment may be granted by the CHMP in exceptional cases, when a medicinal product is expected to be of a major public health interest, particularly from the point of view

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of therapeutic innovation. The timeframe for the evaluation of an MAA under the accelerated assessment procedure is of 150 days, excluding stop-clocks.

National authorization procedures

There are also two other possible routes to authorize medicinal products in several EU countries, which are available for investigational medicinal products that fall outside the scope of the centralized procedure:

Decentralized procedure. Using the decentralized procedure, an applicant may apply for simultaneous authorization in more than one EU country of medicinal products that have not yet been authorized in any EU country and that do not fall within the mandatory scope of the centralized procedure.

Mutual recognition procedure. In the mutual recognition procedure, a medicine is first authorized in one EU member state, in accordance with the national procedures of that country. Following this, further marketing authorizations can be sought from other EU countries in a procedure whereby the countries concerned agree to recognize the validity of the original, national marketing authorization.

Under the above-described procedures, before granting the marketing authorization, the EMA or the competent authorities of the member states of the EEA make an assessment of the risk-benefit balance of the product on the basis of scientific criteria concerning its quality, safety and efficacy.

Conditional approval

In specific circumstances, EU legislation (Article 14(7) Regulation (EC) No 726/2004 and Regulation (EC) No 507/2006 on Conditional Marketing Authorizations for Medicinal Products for Human Use) enables applicants to obtain a conditional marketing authorization prior to obtaining the comprehensive clinical data required for an application for a full marketing authorization. Such conditional approvals may be granted for product candidates (including medicines designated as orphan medicinal products) if (1) the risk-benefit balance of the product candidate is positive, (2) it is likely that the applicant will be in a position to provide the required comprehensive clinical trial data, (3) the product fulfills unmet medical needs and (4) the benefit to public health of the immediate availability on the market of the medicinal product concerned outweighs the risk inherent in the fact that additional data are still required. A conditional marketing authorization may contain specific obligations to be fulfilled by the marketing authorization holder, including obligations with respect to the completion of ongoing or new studies, and with respect to the collection of pharmacovigilance data. Conditional marketing authorizations are valid for one year, and may be renewed annually, if the risk-benefit balance remains positive, and after an assessment of the need for additional or modified conditions or specific obligations. The timelines for the centralized procedure described above also apply with respect to the review by the CHMP of applications for a conditional marketing authorization.

Pediatric studies

Prior to obtaining a marketing authorization in the European Union, applicants have to demonstrate compliance with all measures included in an EMA-approved Pediatric Investigation Plan, or PIP, covering all subsets of the pediatric population, unless the EMA has granted a product-specific waiver, a class waiver, or a deferral for one or more of the measures included in the PIP. The respective requirements for all marketing authorization procedures are set forth in Regulation (EC) No 1901/2006, which is referred to as the Pediatric Regulation. This requirement also applies when a company wants to add a new indication, pharmaceutical form or route of administration for a medicine that is already authorized. The Pediatric Committee of the EMA, or PDCO, may grant deferrals for some medicines, allowing a company to delay development of the medicine in children until there is enough information to demonstrate its effectiveness and safety in adults. The PDCO may also grant waivers when development of a medicine in children is not needed or is not appropriate, such as for diseases that only affect the elderly population.

Before a marketing authorization application can be filed, or an existing marketing authorization can be amended, the EMA determines that companies actually comply with the agreed studies and measures listed in each relevant PIP.

European Union regulatory exclusivity

In the European Union, new products authorized for marketing (i.e., reference products) qualify for eight years of data exclusivity and an additional two years of market exclusivity upon marketing authorization. The data exclusivity period prevents generic or biosimilar applicants from relying on the pre-clinical and clinical trial data contained in the dossier of the reference product

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when applying for a generic or biosimilar marketing authorization in the European Union during a period of eight years from the date on which the reference product was first authorized in the European Union. The market exclusivity period prevents a successful generic or biosimilar applicant from commercializing its product in the EU until ten years have elapsed from the initial authorization of the reference product in the EU. The ten-year market exclusivity period can be extended to a maximum of eleven years if, during the first eight years of those ten years, the marketing authorization holder obtains an authorization for one or more new therapeutic indications which, during the scientific evaluation prior to their authorization, are held to bring a significant clinical benefit in comparison with existing therapies.

European Union orphan designation and exclusivity

The criteria for designating an orphan medicinal product in the European Union, are similar in principle to those in the United States. Under Article 3 of Regulation (EC) 141/2000, a medicinal product may be designated as orphan if (1) it is intended for the diagnosis, prevention or treatment of a life-threatening or chronically debilitating condition; (2) either (a) such condition affects no more than five in 10,000 persons in the European Union when the application is made, or (b) the product, without the benefits derived from orphan status, would not generate sufficient return in the European Union to justify investment; and (3) there exists no satisfactory method of diagnosis, prevention or treatment of such condition authorized for marketing in the European Union, or if such a method exists, the product will be of significant benefit to those affected by the condition, as defined in Regulation (EC) 847/2000. Orphan medicinal products are eligible for financial incentives such as reduction of fees or fee waivers and are, upon grant of a marketing authorization, entitled to ten years of market exclusivity for the approved therapeutic indication. The application for orphan designation must be submitted before the application for marketing authorization. The applicant will receive a fee reduction for the marketing authorization application if the orphan designation has been granted, but not if the designation is still pending at the time the marketing authorization is submitted. Orphan designation does not convey any advantage in, or shorten the duration of, the regulatory review and approval process.

The ten-year market exclusivity in the European Union may be reduced to six years if, at the end of the fifth year, it is established that the product no longer meets the criteria for orphan designation, for example, if the product is sufficiently profitable not to justify maintenance of market exclusivity. Additionally, marketing authorization may be granted to a similar product for the same indication at any time if:

The second applicant can establish that its product, although similar, is safer, more effective or otherwise clinically superior;

The applicant consents to a second orphan medicinal product application; or

The applicant cannot supply enough orphan medicinal product.

PRIME designation

The EMA grants access to the Priority Medicines, or PRIME, program to investigational medicines for which it determines there to be preliminary clinical data available showing the potential to address an unmet medical need and bring a major therapeutic advantage to patients. Many benefits accrue to sponsors of product candidates with PRIME designation, including but not limited to, early and proactive regulatory dialogue with the EMA, frequent discussions on clinical trial designs and other development program elements, and accelerated marketing authorization application assessment once a dossier has been submitted. Importantly, a dedicated Agency contact and rapporteur from the Committee for Human Medicinal Products, or CHMP, or Committee for Advanced Therapies, or CAT, are appointed early in PRIME scheme facilitating increased understanding of the product at EMA’s Committee level. A kick-off meeting initiates these relationships and includes a team of multidisciplinary experts at the EMA to provide guidance on the overall development and regulatory strategies.

A marketing authorization is valid for five years in principle and the marketing authorization may be renewed after five years on the basis of a re-evaluation of the risk-benefit balance by the EMA or by the competent authority of the authorizing member state. To this end, the marketing authorization holder must provide the EMA or the competent authority with a consolidated version of the file in respect of quality, safety and efficacy, including all variations introduced since the marketing authorization was granted, at least six months before the marketing authorization ceases to be valid. Once renewed, the marketing authorization is valid for an unlimited period, unless the European Commission or the competent authority decides, on justified grounds relating to pharmacovigilance, to proceed with one additional five-year renewal. Any authorization which is not followed by the actual placing of the drug on the E.U. market (in case of centralized procedure) or on the market of the authorizing member state within three years after authorization ceases to be valid (the so-called sunset clause).

United Kingdom Regulation

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From January 1, 2021, European Union law no longer directly applies in the United Kingdom. The United Kingdom has adopted existing European Union medicines regulation as standalone United Kingdom legislation with some amendments to reflect procedural and other requirements with respect to marketing authorizations and other regulatory provisions.

The Medicines and Healthcare products Regulatory Agency, or MHRA is responsible for regulating the United Kingdom medicinal products market (Great Britain and Northern Ireland). In order to market medicines in the United Kingdom, manufacturers must hold a United Kingdom authorization. On January 1, 2021, all European Union marketing authorizations were converted to United Kingdom marketing authorizations subject to a manufacturer opt-out. The United Kingdom has introduced a separate UK-specific processes for regulatory submissions and medicinal product marketing authorization, and the MHRA guidance states that the United Kingdom will have the power to take into account marketing authorizations made under the European Union decentralized and mutual recognition procedures. On January 1, 2024, the MHRA launched the International Recognition Procedure, or IRP, which provides for an expedited authorization procedure for products that have received positive marketing authorization decisions from trusted partner agencies, such as the EMA or the FDA. There are two available routes for assessment and recognition under the IRP:

Recognition Route A – 60 days from validation of submission

Application must be based on a Reference Regulatory, or RR, marketing authorization within the previous two years

Any significant differences from the quality dossier approved by the RR requires assessment under Recognition Route B

Evidence of GMP compliance for manufacturing sites should be provided with submission

None of the Recognition Route B criteria are met

Recognition Route B - 110 days from validation of submission with one planned clock stop (up to 60 days) at day 70 to allow applicant to respond to issues identified during review

Application must be based on a RR marketing authorization within the previous ten years.

Criteria requiring Recognition Route B include, among other things:

The RR granted a conditional or exceptional circumstances marketing authorization

Additional manufacturing sites included in the application were not assessed by the RR or a manufacturing site is not GMP certified

There are substantial changes to the manufacturing process compared to the process approved by the RR

Certain product types (e.g., advanced therapy medicinal products, orphan medicines, over-the-counter medicines)

A Risk Management Plan was not assessed by the RR

The RR required one or more post-authorization safety studies for the product

A companion diagnostic is necessary for correct use of the product

United Kingdom medicines legislation is subject to future regulatory change under the Medicines and Medical Devices Act 2021. This act sets out a new framework for the adoption of medicines regulation.

Different rules will apply in Northern Ireland following implementation of the Northern Ireland Protocol. In Northern Ireland, European Union central marketing applications will continue to apply.

The Trade and Cooperation Agreement, which sets forth a framework for partnership between the European Union and the United Kingdom, became effective as of January 1, 2021. The Trade and Cooperation Agreement contains an Annex in relation to medicinal products with the objective of facilitating availability of medicines, promotion of public health and consumer protection in respect of medicinal products between the United Kingdom and the European Union. The Annex provides for mutual recognition of Good Manufacturing Practice (GMP) inspections and certificates, meaning that manufacturing facilities do not need to undergo duplicate inspections for the two markets. The Annex establishes a Working Group on Medicinal Products to deal with matters under the Trade and Cooperation Agreement, facilitate co-operation and for the carrying out of technical discussions. It is expected that further bilateral discussions will continue with respect to regulatory areas not the subject of the Trade and Cooperation Agreement, including pharmacovigilance. The Trade and Cooperation Agreement also does not include reciprocal arrangements for the recognition of batch testing certification. However, the United Kingdom has listed approved countries, including the EEA which will

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enable United Kingdom importers and wholesales to recognize certain certification and regulatory standards. The European Commission has not adopted such recognition procedures.

It is expected that the establishment of a separate United Kingdom authorization system, albeit with transitional recognition procedures in the United Kingdom, will lead to additional regulatory costs. In addition, additional regulatory costs will be incurred with respect to the lack of mutual recognition of batch testing and related regulatory measures.

Rest of the world regulation

For other countries outside of the European Union and the United States, such as countries in Eastern Europe, Latin America or Asia, the requirements governing the conduct of clinical trials, product licensing, pricing and reimbursement vary from jurisdiction to jurisdiction. Additionally, the clinical trials must be conducted in accordance with GCP requirements and the applicable regulatory requirements and the ethical principles that have their origin in the Declaration of Helsinki.

If we fail to comply with applicable foreign regulatory requirements, we may be subject to, among other things, fines, suspension or withdrawal of regulatory approvals, product recalls, seizure of products, operating restrictions and criminal prosecution.

Coverage, Pricing and Reimbursement

Sales of pharmaceutical products depend in significant part on the availability of third-party coverage and reimbursement. Third-party payors include government healthcare programs such as Medicare, managed care providers, private health insurers and other organizations. We anticipate third-party payors will provide reimbursement for our products. However, these third-party payors are increasingly challenging the price and examining the cost effectiveness of medical products and services. In addition, significant uncertainty exists as to the reimbursement status of newly approved healthcare products. The process for determining whether a payor will provide coverage for a product may be separate from the process for setting the price or reimbursement rate that the payor will pay for the product once coverage is approved. Third-party payors often rely on Medicare coverage policy and payment limitations in setting their own reimbursement rates but also have their own methods to individually establish coverage and reimbursement policies. As a result, obtaining coverage and adequate reimbursement can be a time-consuming and costly process. Third-party payors may limit coverage to specific products on an approved list, or formulary, which might not include all of the approved products for a particular indication. We may need to conduct expensive pharmacoeconomic studies in order to demonstrate the medical necessity and cost effectiveness of our products. Moreover, a payor’s decision to provide coverage for a drug product does not imply that an adequate reimbursement rate will be approved. Third-party reimbursement may not be sufficient to maintain price levels high enough to realize an appropriate return on investment in product development. Our product candidates may not be considered cost effective. It is time-consuming and expensive for us to seek reimbursement from third-party payors. Reimbursement may not be available or sufficient to allow us to sell our products on a competitive and profitable basis.

Medicare is a federal healthcare program administered by the federal government that covers individuals aged 65 and over as well as individuals with certain disabilities. Drugs may be covered under one or more sections of Medicare depending on the nature of the drug and the conditions associated with and site of administration. For example, under Part D, Medicare beneficiaries may enroll in prescription drug plans offered by private entities which provide coverage for outpatient prescription drugs. Part D plans include both stand-alone prescription drug benefit plans and prescription drug coverage as a supplement to Medicare Advantage plans. Unlike Medicare Parts A and B, Part D coverage is not standardized. Part D prescription drug plan sponsors are not required to pay for all covered Part D drugs, and each drug plan can develop its own drug formulary that identifies which drugs it will cover and at what tier or level.

Medicare Part B covers most injectable drugs given in an in-patient setting and some drugs administered by a licensed medical provider in hospital outpatient departments and doctors’ offices. Medicare Part B is administered by Medicare Administrative Contractors, which generally have the responsibility of making coverage decisions. Subject to certain payment adjustments and limits, Medicare generally pays for a Part B-covered drug based on a percentage of manufacturer-reported average sales price, which is regularly updated. We believe that our product candidates that are intended to be administered intratumorally will be subject to the Medicare Part B rules.

We expect that there will continue to be a number of federal and state proposals to implement governmental pricing controls and limit the growth of healthcare costs, including the cost of prescription drugs. For example, the ACA enacted in March 2010, was expected to have a significant impact on the health care industry. The ACA has been under scrutiny by the U.S. Congress almost since its passage, and certain sections of the ACA have not been fully implemented or effectively repealed. As a result, its longevity continues to be uncertain. In addition, ongoing initiatives in the U.S. have increased and will continue to increase pressure on drug pricing. The announcement or adoption of any such initiative could have an adverse effect on potential revenues from any product candidate that we may successfully develop.

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In addition, in some foreign countries, the proposed pricing for a drug must be approved before it may be lawfully marketed. The requirements governing drug pricing vary widely from country to country. Moreover, a payor’s decision to provide coverage for a drug product does not imply that an adequate reimbursement rate will be approved. Third-party reimbursement may not be sufficient to maintain price levels high enough to realize an appropriate return on investment in product development. For example, the European Union provides options for its member states to restrict the range of medicinal products for which their national health insurance systems provide reimbursement and to control the prices of medicinal products for human use. A member state may approve a specific price for the medicinal product, or it may instead adopt a system of direct or indirect controls on our profitability placing the medicinal product on the market. Other member states allow companies to fix their own prices for drug products but monitor and control prescription volumes and issue guidance to physicians to limit prescriptions. There can be no assurance that any country that has price controls or reimbursement limitations for pharmaceutical products will allow favorable reimbursement and pricing arrangements for any of our products. Historically, products launched in the European Union and other countries do not follow price structures of the United States and generally prices tend to be significantly lower.

The downward pressure on health care costs in general, particularly prescription drugs, has become intense. As a result, increasingly high barriers are being erected to the entry of new products. In addition, there can be considerable pressure by governments and other stakeholders on prices and reimbursement levels, including as part of cost containment measures. Political, economic and regulatory developments may further complicate pricing negotiations, and pricing negotiations may continue after reimbursement has been obtained. Reference pricing used by various EU member states and parallel distribution (arbitrage between low-priced and high-priced member states) can further reduce prices. Any country that has price controls or reimbursement limitations for drug products may not allow favorable reimbursement and pricing arrangements.

Other U.S. Health Care Laws and Regulations

If our product candidates are approved in the United States, we will have to comply with various U.S. federal and state laws, rules and regulations pertaining to health care fraud and abuse, including anti-kickback laws and physician self-referral laws, rules and regulations. Violations of the fraud and abuse laws are punishable by criminal and civil sanctions, including, in some instances, exclusion from participation in federal and state health care programs, including Medicare and Medicaid. These laws include:

The federal anti-kickback statute prohibits, among other things, persons from knowingly and willfully soliciting, offering, receiving or paying remuneration, directly or indirectly, in cash or in kind, to induce or reward either the referral of an individual for, or the purchase, order or recommendation of, any good or service, for which payment may be made, in whole or in part, under a federal health care program such as Medicare and Medicaid. A person or entity does not need to have actual knowledge of the AKS or specific intent to violate it to have committed a violation. In addition, the government may assert that a claim including items or services resulting from a violation of the AKS constitutes a false or fraudulent claim for purposes of the FCA or federal civil money penalties statute;

The federal civil and criminal false claims laws and civil monetary penalty laws, including the federal False Claims Act, which prohibit, among other things, individuals or entities from knowingly presenting, or causing to be presented, false or fraudulent claims for payment to, or approval by Medicare, Medicaid, or other federal health care programs, knowingly making, using or causing to be made or used a false record or statement material to a false or fraudulent claim or an obligation to pay or transmit money to the federal government, or knowingly concealing or knowingly and improperly avoiding or decreasing or concealing an obligation to pay money to the federal government. Manufacturers can be held liable under the FCA even when they do not submit claims directly to government payers if they are deemed to “cause” the submission of false or fraudulent claims. The FCA also permits a private individual acting as a “whistleblower” to bring actions on behalf of the federal government alleging violations of the FCA and to share in any monetary recovery;

The federal Health Insurance Portability and Accountability Act of 1996, or HIPAA, imposes criminal and civil liability for executing a scheme to defraud any health care benefit program or making false statements relating to health care matters;

HIPAA, as amended by the Health Information Technology for Economic and Clinical Health Act, or HITECH Act, and its implementing regulations, also imposes obligations, including mandatory contractual terms, with respect to safeguarding the privacy, security and transmission of individually identifiable health information;

The federal transparency requirements under the Physician Payments Sunshine Act require manufacturers of FDA-approved drugs, devices, biologics and medical supplies covered by Medicare, Medicaid or the Children’s Health Insurance Program to report, on an annual basis, to the Centers for Medicare and Medicaid Services (CMS) information related to payments and other transfers of value to physicians, certain advanced non-physician health care practitioners, and teaching hospitals or to entities or individuals at the request of, or designated on behalf of, such physicians, non-physician health care practitioners, and teaching hospitals as well as certain ownership and investment interests held by physicians and their immediate family members; and

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Analogous state and foreign laws and regulations, such as state anti-kickback and false claims laws, may apply to sales or marketing arrangements and claims involving health care items or services reimbursed by nongovernmental third-party payors, including private insurers.

In November 2020, HHS finalized significant changes to the regulations implementing the Anti-Kickback Statute, as well as the Physician Self-Referral Law (Stark Law) and the civil monetary penalty rules regarding beneficiary inducements, with the goal of offering the healthcare industry more flexibility and reducing the regulatory burden associated with those fraud and abuse laws, particularly with respect to value-based arrangements among industry participants.

Source: SEC EDGAR (public domain) · 10-K for the period ended 2024-12-31, filed 2025-03-06 · accession 0000950170-25-034820

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