Seres Therapeutics Status update Earnings Report

Seres Therapeutics EPS Results

• Actual EPS: -$1.89
• Consensus EPS: -$2.39
• Beat/Miss: Beat by +$0.50
• One Year Ago EPS: N/A

Seres Therapeutics Revenue Results

• Actual Revenue: $0.44 million
• Expected Revenue: N/A
• Beat/Miss: N/A
• YoY Revenue Growth: N/A

Seres Therapeutics Announcement Details

• Quarter: Status update
• Date: 3/12/2026
• Time: Before Market Opens
• Conference Call Date: N/A
• Conference Call Time: N/A

Seres Therapeutics (NASDAQ:MCRB) is a clinical‐stage microbiome therapeutics company focused on harnessing the power of the human microbiome to treat serious diseases. Headquartered in Cambridge, Massachusetts, Seres applies proprietary microbiome science and manufacturing capabilities to develop a pipeline of living microbial therapies designed to restore healthy gut function. The company’s approach leverages understanding of microbial ecology and human biology to address conditions where the native microbiome is disrupted.

Among its lead candidates is SER-109, an investigational oral microbiome therapeutic for reducing recurrence of Clostridioides difficile infection. Seres is also advancing SER-287 in ulcerative colitis, SER-401 in combination with immunotherapy for certain cancers, and other preclinical programs targeting metabolic and inflammatory diseases. The company collaborates with strategic partners, including Nestlé Health Science, to support development, manufacturing scale-up and global research efforts.

Founded in 2010, Seres went public in 2015 to further accelerate its clinical pipeline. The management team comprises experienced biotech executives, clinicians and scientists with expertise in microbiome research and product development. Seres continues to conduct multi‐center clinical trials across North America and Europe, seeking to bring first‐in‐class microbiome therapies to patients with limited treatment options.

Seres Therapeutics Status update Earnings Call Transcript

Key Takeaways

• Positive Sentiment: The investigator‑sponsored SER‑155 study in immune checkpoint inhibitor‑related colitis is fully enrolled (15 patients) and initial safety, efficacy, pharmacology and biomarker data are expected in Q2, providing a near‑term clinical catalyst.
• Neutral Sentiment: SER‑603 is a preclinical live biotherapeutic aimed at microbiome‑driven mechanisms in IBD; IND‑enabling work is underway and Seres is exploring collaborations to advance development.
• Negative Sentiment: The planned phase II SER‑155 allo‑HSCT program is largely prepared (protocol submitted, CRO selected, drug substance manufactured) but further start‑up activities have been paused pending funding, delaying study initiation.
• Negative Sentiment: As of 12/31/25 Seres reported approximately $45.8M in cash (including ~$12.2M raised in Q4) and expects to fund operations only through the third quarter, prompting cost cuts and making near‑term financing or partnerships critical.

Presentation

[Operator]

Thank you for standing by. At this time, I would like to welcome everyone to the Seres Therapeutics Corporate Update Conference Call. All lines have been placed on mute to prevent any background noise. After the speaker's remarks, there will be a question and answer session. If you would like to ask a question during this time, simply press star followed by the number one on your telephone keypad. If you would like to withdraw your question, again, press the star one. I would now like to turn the conference over to Dr. Carlo Tanzi of Investor Relations. You may begin.

[Carlo Tanzi, Investor Relations at Seres Therapeutics]

Thank you and good morning. Before we begin, I'd like to remind everyone that we're making forward-looking statements, including statements regarding the impact of our recent management transitions and appointments, our strategy, clinical development plans, anticipated data readouts, regulatory interactions, efforts to secure funding and/or partnerships, operating plans, our drug candidates and their potential impacts and outcomes, and our expected cash runway. These statements are subject to risks and uncertainties described in our SEC filings. Actual results may differ materially. We undertake no obligation to update these statements except as required by law.

[Carlo Tanzi, Investor Relations at Seres Therapeutics]

On today's call, prepared remarks will be made by Richard Kender, Executive Chair and Interim Chief Executive Officer, Dr. Matthew Henn, President and Chief Scientific Officer, Kelly Brady, Chief Operating Officer, and Marella Thorell, Chief Financial Officer. Additional members of the management team will be available for Q&A. With that, I'll turn the call over to Rich.

[Richard Kender, Executive Chair and Interim CEO at Seres Therapeutics]

Thank you, Carlo. Good morning, everyone. I am very pleased to be leading Seres at this important time. As a longtime board member serving more than 11 years, I've had the opportunity to closely observe the evolution of the company's live biotherapeutic platform and pipeline and witness the difference our drugs and drug candidates have made for patients and see the scientific rigor of our underlying programs. I know the Seres leadership team well. I understand the strong capabilities of the organization. I'm confident in the numerous opportunities to leverage our platform to deliver significant impact and, in some cases, life-saving therapies to patients. I accepted this role because I believe in the company has differentiated science with the potential to address important unmet medical needs in a fundamentally novel way.

[Richard Kender, Executive Chair and Interim CEO at Seres Therapeutics]

My 35 years in biopharma, including a career at Merck in a role spanning M&A, licensing, financial evaluation analysis, and global competitive intelligence, as well as my experience in navigating complexities in biotechs that are both numerous public and private company boards, which I have, which have positioned me well to lead Seres on our mission. I am pleased to work closely with the Seres executive team, including Matt Henn in his new role as President and CSO, Kelly Brady, newly appointed COO, and Tom and Marela, who have provided strong leadership to Seres through the strategic shift, along with the rest of the Seres leadership team. Since the company's founding 15 years ago by Flagship Pioneering, Seres has built a differentiated field leading and proven scientific foundation on which to advance drugs that harness the therapeutic potential of microbiomes.

[Richard Kender, Executive Chair and Interim CEO at Seres Therapeutics]

The development, FDA approval, and the launch of VOWST, the first ever oral microbiome therapeutic, validated the platform and demonstrated both the company and team's ability to navigate the complex regulatory pathway required for novel therapeutic modality. Kelly, Matt, and our current leaders in manufacturing, quality, regulatory, medical affairs, and R&D were instrumental in getting VOWST from the concept to the market. We will benefit from their experiences establishing Seres' core live biotherapeutic technology and navigating the approval pathway to the novel modality as we advance our early-stage programs. Our strategy is focused and disciplined, centered on advancing live biotherapeutic programs supported by strong scientific rationale and clear commercial potential. A key priority continues to be securing funding for our programs, including potential collaborations with organizations aligned with our vision to advance these programs efficiently and to drive long-term value for shareholders.

[Richard Kender, Executive Chair and Interim CEO at Seres Therapeutics]

As we move forward, we will focus on our promising live biotherapeutic programs in inflammatory and immune disease. In the near term, we are supporting the upcoming readout of the ongoing, fully enrolled investigator-sponsored SER-155 study with Memorial Sloan Kettering Cancer Center, evaluating patients with immune checkpoint inhibitor-related colitis or irEC. We look forward to these clinical data in the second quarter of this year. This indication is among the most frequent and severe immune-related adverse events observed in recipients of immune checkpoint inhibitor or ICI therapy and could represent an important therapeutic and commercial opportunity for Seres. Immunotherapeutics are commonly used across tumor types, representing a landmark innovation in cancer treatment. The best-selling drug in this space, Merck's Keytruda, alone reached $32 billion in global sales in 2025, highlighting the magnitude of ICIs and therefore the potential scope of the need for irEC therapies.

[Richard Kender, Executive Chair and Interim CEO at Seres Therapeutics]

Turning to our SER-603 program, in a moment, Matt will share more about the potential of this asset in IBD and potential collaboration opportunities. Given the chronic nature of IBD, the size of the market. The continued unmet need for safe, durable, non-immunosuppressant treatment options, we believe SER-603 has the potential to address a substantial commercial opportunity. Over the past year, as Kelly will further elaborate on, Seres has made excellent progress with phase 2 readiness activities to support the further development of SER-155 to prevent bloodstream infections in patients undergoing allo-HSCT treatment. With strong phase 1B data underscoring the clinical rationale and supportive from KOLs as to the need to address inadequate options for preventing bloodstream infections in patients receiving transplants to treat blood cancers, we continue to work to secure funding to initiate that study. With that, I'll turn it over to Matt.

[Matthew Henn, President and Chief Scientific Officer at Seres Therapeutics]

Thank you, Rich. In connection with our strategic focus, I'm pleased to assume the role of President alongside my responsibilities as Chief Scientific Officer and collaborate with Rich and the rest of the executive team to successfully advance getting our innovative drug technology to patients with significant unmet medical needs. Our early-stage pipeline programs are focused on inflammatory and immune diseases, or I&I, with a primary focus to date on inflammatory bowel disease, or IBD, and immune-related enterocolitis, or irEC. Kelly will speak about our investigator sponsor trial in irEC at Memorial Sloan Kettering Cancer Center in just a moment. A key element of our pipeline strategy is advancing SER-603, a preclinical stage biotherapeutic product or LBP candidate optimized to address disruptions in the GI microbiome and improve mucosal barrier integrity, key drivers of inflammation in IBD patients that are not currently targeted by existing therapeutics.

[Matthew Henn, President and Chief Scientific Officer at Seres Therapeutics]

SER-603 is designed to inhibit inflammatory bacteria and their associated metabolites, to promote epithelial barrier integrity, to reduce the translocation of inflammatory molecules and barrier inflammation, and to promote immune homeostasis by inducing non-immunosuppressive Regulatory T cell responses. Many IBD patients experience an efficacy ceiling due to non-response or poor durability of response to existing therapies. Further, most approved therapies target downstream inflammatory and immune responses. In addition, the majority of these approaches are immunosuppressive, leading to toxicities and limitations of use in combination therapy. We believe that SER-603 has the potential to serve as a non-immunosuppressive treatment option for I&I diseases linked to colitis. We believe the therapeutic opportunity could be substantial with the ability to target causes of inflammation that are not currently addressed with existing therapies, utilizing both mono and combination therapy strategies without the potential added risk of increased toxicity.

[Matthew Henn, President and Chief Scientific Officer at Seres Therapeutics]

Our research to date on SER-603 has been primarily supported through a partnership with the Crohn's & Colitis Foundation. We continue to explore additional opportunities for collaborations with other entities, particularly those with an established franchise in IBD. We are currently conducting IND-enabling activities for SER-603 as we plan for further development of this program. I'd also like to note that Seres continues to have a highly productive, long-standing collaboration with the Combating Antibiotic-Resistant Bacteria Biopharmaceutical Accelerator, also known as CARB-X. With their support, we are progressing the development of an oral liquid formulation of an LBP based on SER-155 strains for patients unable to take capsules, including ICU patients and other medically vulnerable populations at high risk of antimicrobial-resistant infections. Progressing liquid formulation technologies could have broad applicability with benefits not just in infection, but also in the context of the treatment of pediatric and I&I patients.

[Matthew Henn, President and Chief Scientific Officer at Seres Therapeutics]

I'll now turn the call over to Kelly to provide an update on our clinical activities.

[Kelly Brady, Chief Operating Officer at Seres Therapeutics]

Thanks, Matt. In terms of current clinical activities, we have an ongoing investigator-sponsored trial of SER-155 in patients with irEC being conducted in collaboration with Memorial Sloan Kettering, or MSK, Cancer Center. We have been collaborating with MSK for over a decade on the impact of the gastrointestinal microbiome on immune-related diseases and cancer. We are very pleased to leverage their expertise in this study. The SER-155 irEC study is now fully enrolled with 15 participants and clinical data are on track for release in Q2. The readout is expected to include initial safety, efficacy, pharmacology, and exploratory biomarker data. We also expect to prepare a historical reference cohort with MSK to contextualize the data readout. These data have the potential to clarify the opportunity for SER-155 in both irEC as well as more broadly in other applications.

[Kelly Brady, Chief Operating Officer at Seres Therapeutics]

irEC is a major clinical problem faced by many cancer patients and is among the most frequent and severe immune-related adverse events seen in recipients of ICI therapy. This complication is observed in up to 50% of ICI patients, with rates varying based on cancer drug and treatment regimen. Current treatment approaches for irEC include immunosuppressive steroids, which have significant limitations, including toxicity and the potential reduction of antitumor efficacy as patients come off their checkpoint inhibitor therapy. SER-155 is designed to allow patients to remain on or reintroduce ICI therapy while avoiding systemic immunosuppression. Links between the microbiome and response to ICI therapy, as well as incidents of colitis, have been established in the literature. Live biotherapeutics targeting the microbiome such as SER-155 may uniquely address gut epithelial barrier integrity, offering a novel solution.

[Kelly Brady, Chief Operating Officer at Seres Therapeutics]

I am also pleased to report progress on our SER-155 Allo-HSCT phase II preparation efforts. Our interest in advancing SER-155 in this setting is grounded in the prior clinical results, demonstrating a 77% relative risk reduction in bloodstream infections, accompanied by consistent biomarker findings and a well-tolerated safety profile. Based on these positive data and the significant unmet need, SER-155 has received breakthrough therapy designation, which has facilitated our subsequent interactions with the FDA. Over the past year, our team has made meaningful progress on phase II preparatory activities. This includes achieving key milestones such as submitting the final study protocol to the FDA, along with selecting our CRO, engaging with and evaluating potential clinical study sites globally, and manufacturing drug substance for the study.

[Kelly Brady, Chief Operating Officer at Seres Therapeutics]

Importantly, while we have paused further investment at this time in these start-up activities, we have paused the program at a point that preserves value and the ability to efficiently advance the study in the future. Based on our progress, we believe that pending receipt of funding support, we are well prepared to resume the work required to initiate the planned phase II study. Following study initiation, we believe we can obtain the interim clinical results from the phase II study within 12 months of first patient. Positive results from this study, if achieved, could enable timely engagement with the FDA and advancement into a single phase III trial to support registration. I will now pass the call to Marella.

[Marella Thorell, Chief Financial Officer at Seres Therapeutics]

Thanks, Kelly. We plan to report our fourth quarter and full year 2025 financial results via press release next week, so I won't discuss those details today. However, I do want to provide an update on our cash position and runway. As of December 31st, 2025, Seres had approximately $45.8 million in cash and cash equivalents, which includes net proceeds of approximately $12.2 million raised in the fourth quarter of 2025 through the company's at-the-market equity offering program. As recently announced, we have taken action to decrease our operating costs, including a reduction in our workforce. Based on the current cash position and future operating plans, we expect to fund operations through the third quarter of this year. We continue to evaluate additional opportunities to extend our cash runway. I'll now return the call to Rich.

[Richard Kender, Executive Chair and Interim CEO at Seres Therapeutics]

Thank you, Marella. As you have heard from Matt, Kelly, and Marella, Seres is executing a focused strategy across our live biotherapeutic platform and managing our financial resources and team efforts in line with the strategy. We remain committed to advancing our inflammatory and immune programs while preparing for the upcoming irEC clinical data expected in Q2 this year. Our immediate priority is to establish a collaboration that supports the continued advancement of our pipeline towards meaningful development milestones with the goal of delivering differentiated medicines and creating durable shareholder value. Operator, please open the line for questions.

[Kelly Brady, Chief Operating Officer at Seres Therapeutics]

Thank you. As a reminder, to ask a question, you will need to press star, then the number one on your telephone keypad, and if you would like to withdraw your question, press star one again. We'll pause for just a moment to compile the Q&A roster. There are no questions at this time. I will turn the call back over to the management for closing remarks.

[Marella Thorell, Chief Financial Officer at Seres Therapeutics]

Thank you for joining the call today. Have a good day.

[Kelly Brady, Chief Operating Officer at Seres Therapeutics]

That concludes today's call. Thank you all for joining. You may now disconnect.

Participants

Executives

• Carlo Tanzi, Investor Relations
• Kelly Brady, Chief Operating Officer
• Marella Thorell, Chief Financial Officer
• Matthew Henn, President and Chief Scientific Officer
• Richard Kender, Executive Chair and Interim CEO