---
schema_version: "secwatch.filing_event.v1"
accession: "0001193125-25-173985"
form_type: "8-K"
ticker: "MCRB"
cik: "0001609809"
company_name: "Seres Therapeutics, Inc."
filed_at: "2025-08-06T23:59:59+00:00"
generated_at: "2026-05-17T19:30:23.667942+00:00"
event_type: "earnings"
sentiment: "neutral"
materiality_score: 0.7
calibrated_materiality_score: 0.7
confidence: "high"
source: SEC EDGAR
---

# Seres Q2 net loss narrows to $19.9M; CEO replaced; SER-155 Phase 2 protocol filed

## Summary
- Net loss from continuing ops $19.9M in Q2 2025 vs $26.2M in Q2 2024; cash $45.4M as of June 30.
- Received $25M Nestlé installment in July; expects cash runway into Q1 2026.
- Co-CEOs Thomas DesRosier and Marella Thorell appointed Aug 1 after prior CEO Eric Shaff departed.
- SER-155 Phase 2 protocol submitted to FDA for BSI prevention in allo-HSCT; awaiting FDA feedback.
- Engaging with multiple parties on partnerships, out-licensing, or mergers to secure capital.

## SEC filing metadata
- accession: 0001193125-25-173985
- form_type: 8-K
- ticker: MCRB
- cik: 0001609809
- company_name: Seres Therapeutics, Inc.
- filed_at: 2025-08-06T23:59:59+00:00
- event_type: earnings
- sentiment: neutral
- materiality_score: 0.7
- calibrated_materiality_score: 0.7
- confidence: high
- sec_items: 2.02, 7.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1609809/000119312525173985/0001193125-25-173985-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1609809/000119312525173985/d930624d8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001193125-25-173985
- JSON: https://secwatch.observer/filing/0001193125-25-173985.json
- Plain text: https://secwatch.observer/filing/0001193125-25-173985.txt

This AI-assisted summary is a reading aid. Review the linked SEC EDGAR filing before relying on any specific claim.