Seres Therapeutics, Inc. · NASDAQ:MCRB
Seres Therapeutics — Investor Presentation (March 2026)
40 slides from Seres Therapeutics's investor presentation, Mar 12, 2026
Slide 1: Seres Company Overview March 2026
Seres Company Overview March 2026 Seres Therapeutics, Inc. © 2026 Exhibit 99.2
Slide 2: Disclaimers: Forward Looking Statements
Disclaimers Forward Looking Statements This communication contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. All statements contained in this communication that do not relate to matters of historical fact should be considered forward-looki
Slide 3: Seres journey to lead in live biotherapeutics
Seres continues on successful journey to lead on delivering on the therapeutic potential of live biotherapeutics (LBPs) 2011 Seres founded 2015 SER-109 Breakthrough Therapy Designation -- Seres goes public $133M IPO 2023 SER-109 FDA approval and launch* -- 2020 SER-109 positive Phase 3 topline -- 88
Slide 4: Focused strategy to advance novel live biotherapeutics and deliver shareholder value
Focused strategy to advance novel live biotherapeutics and deliver shareholder value Advancing promising preclinical live biotherapeutic programs for inflammatory and immune diseases Supporting pending readout of investigator-sponsored SER-155 study in immune checkpoint–related enterocolitis, expect
Slide 5: Pipeline programs and development stage
Program Lead Indication & Development Stage Therapeutic Objectives Potential Additional Indications SER-155 Allogeneic HSCT: Phase 2 Ready: Phase 1b Cohort 2 (placebo controlled) data and exploratory biomarker data announced Immune checkpoint related enterocolitis (irEC) IST readout expected in Q2 2
Slide 6: Accessed functional potential of microbe-host co-evolution
Accessed the vast functional potential of millions of years of co-evolution between microbes and their hosts to prevent and treat diseases Clinical translation on targeting key drivers of disease Mucosal Epithelial Barrier-Immune Interface: Protect and induce regeneration of epithelial barrier in th
Slide 7: Consortia of live commensal bacteria can be used as therapeutics
Consortia of live commensal bacteria can be used as therapeutics Change in microbiome function Bile acids Short-chain fatty acids Tryptophan metabolites Other Restructure microbiome composition Engraftment of drug strains Disrupted Microbiome with functional deficiencies (Disease susceptible) Change
Slide 8: Well tolerated safety profile reduces development risk
Seres’ biotherapeutics and pipeline candidates are expected to have well tolerated safety profile, reducing development risk Sources: Nanayakkara et al, CA Cancer J Clin 2021; Penack et al, Blood Adv 2020; Zheng et al, Infect Dis Ther 2021 Based on GI bacteria naturally found in healthy humans, and
Slide 9: Full stack of live biotherapeutics platform capabilities
Seres has full stack of live biotherapeutics platform capabilities & experience in novel live biotherapeutic modality Field-leading Microbiome biomarker & drug target identification --- strains, metabolites/peptides, genes Seres has built field-leading biological, clinical microbiome, and manufactur
Slide 10: MbTx platform: discovery and product optimization engine
MbTx platform: a discovery and product optimization engine, designed to mine and harness microbe-host functional interactions to address disease Strain Library Seres' curated collection of bacteria that represent broad biological breadth paired with high-resolution screening data – 40,000+ strains,
Slide 11: Manufacturing Platform
Manufacturing Platform: Delivers defined consortia in oral formulations using cost-effective production processes which reflect regulatory benchmarks for LBPs Novel formulations enabling consistent drug product composition, drug stability for distribution, and targeted drug delivery Quality systems
Slide 12: SER-155
SER-155
Slide 13: SER-155 value proposition and target indication
Value Proposition Transformational efficacy and placebo-like safety profile to address frequent, deadly blood stream & AMR infections linked to mortality in allo-HSCT recipients and other blood cancer patients Target Indication & Addressable Patient Initial development in allo-HSCT (~10K US / ~40K w
Slide 14: Allo-HSCT regimen can result in life-threatening complications
Allogeneic hematopoietic stem cell transplant (allo-HSCT) regimen can result in life-threatening complications Only ~60% survival 3 years post-transplant Significant immune compromised patient population ~10% transplant mortality for adults in first 100 days post-transplant Infections are leading ca
Slide 15: Bloodstream infections are a leading cause of death post-transplant
Bloodstream infections (BSIs) are a leading cause of death post-transplant and are increasing in incidence with uptake of PTCy treatment BSI risk increasing due to recent adoption of post-transplant cyclophosphamide (PTCy) for GvHD prophylaxis BSI prevalence high despite standard of care use of anti
Slide 16: HCPs highly concerned about BSIs; major unmet need
Source: Seres primary market research 2024 (Trinity survey of hematologists and infectious disease specialists) Concern driven by high risk of morbidity and mortality in a compromised patient population HCPs have high level of concern for BSIs LOW HIGH 1 2 3 4 5 6 7 Major unmet needs for BSIs Top ne
Slide 17: Efficacy and placebo-like safety in Phase 1b in allo-HSCT
Significant efficacy and placebo-like safety profile in Phase 1b study in allo-HSCT Substantial reduction in pathogen domination in Phase 1b Rapid protection of epithelial barrier integrity in Phase 1b Gut pathogen domination associated with bloodstream infections and mortality SER-155 prevents the
Slide 18: SER-155 Phase 2 ready with indication expansion
SER-155 is Phase 2 ready for patients undergoing allo-HSCT to treat hematologic malignancies and design provides opportunity for adjacent indication expansion Expansion: Auto HSCT Cancer neutropenia AML Phase 2 Allo-HSCT Auto HSCT has strong biologic adjacencies to allo-HSCT with similar treatment a
Slide 19: Addressable patient populations for SER-155
US annual diagnoses or transplants Unmet needs addressed by SER-155 Allo-HSCT ~9,300 Prevent mortality and cost of post-transaction infections Autologous HSCT ~13,500 Prevent mortality and costs of post-transplant infections Broader leukemia & lymphoma population* ~87,000 initial focus Reduce morbid
Slide 20: Viral prophylaxis precedent on commercial opportunity
Viral prophylaxis provides precedent on commercial opportunity in medically vulnerable patients Prevymis - increasingly used for viral infection prophylaxis (e.g., allo-HSCT and solid organ transplant populations) $785M ‘24 WW sales (~30% growth over '23) Reduces CMV infection in allo-HSCT recipient
Slide 21: SER-155 in immune checkpoint-related enterocolitis
Value Proposition First-in-class microbiome therapeutic designed to treat irEC as a result of immune checkpoint inhibitor (ICI) therapies by addressing mucosal healing and reducing inflammation, with the potential to reduce or eliminate the need for high dose systemic corticosteroids (which carry th
Slide 22: SER-603
SER-603
Slide 23: SER-603 value proposition and target indication
Value Proposition An inflammatory microbiome drives non-response to advanced therapies. Live biotherapeutics and unique biomarkers can predict response to biologics and can be leveraged to improve response rates and durability through combination therapy and precision medicine Target Indication & Ad
Slide 24: Key challenges in IBD suggest new therapeutic solutions needed
Key challenges in IBD suggest new therapeutic solutions are needed Efficacy ceiling experienced by many patients due to non-response or poor durability of response Safety concerns limit the potential for combining advanced therapies that are immunosuppressive Current therapies don’t directly target
Slide 25: SER-603 targets inflammatory drivers of IBD
SER-603 designed to target inflammatory drivers of Inflammatory Bowel Disease (IBD) that current standards of care cannot IBD is a mucosal barrier-immune disease Seres IBD Program Inflammatory microbiome Overabundance of pathogenic and inflammatory bacteria Loss of GI barrier integrity Barrier damag
Slide 26: Monotherapy proof of concept in preclinical IBD models
Monotherapy Proof of Concept: SER-603 addresses microbiome-driven inflammation in preclinical disease models of IBD Th1 cells Th17 cells SER-603 intervention reduces fecal lipocalin from inflammatory microbiome SER-603 intervention reduces Th1 and Th17 CD4+ T cells * ** Biomarker-based inflammatory
Slide 27: Combination therapy proof of concept with anti-TNF
Combination Therapy Proof of Concept: SER-603 increases the efficacy of anti-TNF�� therapy in a preclinical model of microbiome-driven inflammation GF IL10-/-mice Biomarker (+) microbiome test article ~4-5 weeks of colonization Evaluate treatment effect of SER-603 in combination with anti-TNF�� to a
Slide 28: Biomarker validation predicts response to therapy
Biomarker Validation: Identified bacterial features can predict response to therapy in clinical datasets 8% of Seres biomarker (+) patients experience remission, suggesting patients that have an inflammatory microbiome are very unlikely to respond to Ustekinumab, and may be candidates for combinatio
Slide 29: SER-147
SER-147
Slide 30: SER-147 value proposition and target indication
Value Proposition Leverage clinically proven mechanism with potentially transformative efficacy and placebo-like safety profile to reduce infection and other decompensating events in chronic liver disease patients Target Indication & Addressable Patient Decompensated cirrhosis ~500K US patients ~2.3
Slide 31: Preclinical reduction in SBP bacteria and epithelial barrier protection
Significant protection of epithelial barrier integrity against inflammatory-cytokine driven damage Reduces abundance of pathogens causing most common infections in cirrhosis patients Declining E. coli titers Multi-log reduction in E. coli in in vitro model (above); data for additional antimicrobial
Slide 32: Path Forward
Path Forward
Slide 33: Summary and path forward
Summary and path forward SER-155 Phase 1b placebo-controlled results in allo-HSCT promising, Phase 2 ready Final Phase 2 study protocol submitted to FDA; commencement of study is funding dependent Administration of SER-155 associated with 77% relative risk reduction for BSIs, significant reduction i
Slide 34: Appendix: SER-155 allo-HCT Phase 1b Study Results
Appendix --- SER-155 allo-HCT Phase 1b Study Results
Slide 35: SER-155 Phase 1b study design
SER-155 Phase 1b study evaluated safety, pharmacology, and efficacy in adult allo-HSCT recipients SER-155 COHORT 1 Open-label (n=15 enrolled) COHORT 2 Placebo-controlled 1:1 (n=45 enrolled) SER-155 Placebo results reported May 2023 results announced Sept. 2024 Primary Endpoints: Safety and tolerabil
Slide 36: SER-155 Safety: well tolerated with no treatment-related SAEs
SER-155 Safety: SER-155 was generally well tolerated with no treatment-related SAEs Treatment-emergent adverse events (TEAEs) All but one subject in the placebo arm experienced at least 1 TEAE Most common for SER-155 treated subjects (≥50% and with Δ ≥5% greater than placebo): diarrhea (86% vs. 74%
Slide 37: SER-155 Efficacy: 77% relative risk reduction in bacterial BSIs
SER-155 Efficacy: SER-155 associated with 77% relative risk reduction in bacterial BSIs and reduction in systemic antibiotic exposure Bloodstream infections Significant decrease in bacterial bloodstream infections in SER-155-treated subjects vs. placebo with 77% relative risk reduction Numerically l
Slide 38: Bloodstream infections from HSCT Day 0 to Day 100
Bloodstream infections from HSCT Day 0 to Day 100: Lower incidence in SER-155 treated subjects vs. placebo Bloodstream infections from Day 0 to Day 100 (# patients) SER-155 n=20 n (%) Placebo n=14 n (%) Subjects with confirmed BSI 2 (10.0) 6 (42.9) 95% confidence interval (1.2, 31.7) (17.7, 71.1) Od
Slide 39: Cumulative exposure to systemic antibacterials/antimycotics through Day 100
Cumulative exposure to systemic treatment antibacterials / antimycotics through HSCT Day 100: Lower incidence in SER-155 treated subjects vs. placebo Cumulative Antibacterial or Antimycotic Exposure (HSCT Days) SER-155 n=20 n (SD) Placebo n=14 n (SD) Mean (SD) 9.2 (5.44) 21.1 (20.31) Median 9.0 14.0
Slide 40: Cumulative exposure rate to systemic antibacterials/antimycotics
Cumulative exposure rate to systemic treatment antibacterials / antimycotics through HSCT Day 100: Lower incidence in SER-155 treated subjects vs. placebo Cumulative Antibacterial or Antimycotic Exposure Rate SER-155 n=20 Rate (SD) Placebo n=14 Rate (SD) Mean (SD) 0.090 (0.0530) 0.305 (0.2898) Media
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