---
schema_version: "secwatch.filing_event.v1"
accession: "0001193125-26-346855"
form_type: "8-K"
ticker: "SPRO"
cik: "0001701108"
company_name: "Spero Therapeutics, Inc."
filed_at: "2026-08-12T20:09:26+00:00"
generated_at: "2026-08-12T20:10:10.561033+00:00"
event_type: "earnings"
sentiment: "positive"
materiality_score: 0.75
calibrated_materiality_score: 0.75
confidence: "high"
source: SEC EDGAR
---

# Spero Q2 net loss widens to $9.6M; FDA approves Utebzi, $105M financing extends runway

## Summary
- Net loss of $9.6M ($0.16 diluted EPS) vs $1.7M loss ($0.03) in Q2 2025.
- No revenue in Q2 2026 vs $14.2M in Q2 2025; all deferred revenue previously recognized.
- Cash $50.8M at June 30, 2026; plus $105M royalty financing extends runway into H2 2029.
- FDA approved Utebzi (tebipenem pivoxil) for cUTIs in June 2026; GSK launch expected by end of 2026.
- Exclusive license with Innovent for SP001 (anti-CD40L) worldwide ex-Greater China; Phase 2 in IgG4-RD planned.

## SEC filing metadata
- accession: 0001193125-26-346855
- form_type: 8-K
- ticker: SPRO
- cik: 0001701108
- company_name: Spero Therapeutics, Inc.
- filed_at: 2026-08-12T20:09:26+00:00
- event_type: earnings
- sentiment: positive
- materiality_score: 0.75
- calibrated_materiality_score: 0.75
- confidence: high
- sec_items: 2.02, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1701108/000119312526346855/0001193125-26-346855-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1701108/000119312526346855/d69249d8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001193125-26-346855
- JSON: https://secwatch.observer/filing/0001193125-26-346855.json
- Plain text: https://secwatch.observer/filing/0001193125-26-346855.txt

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