---
schema_version: "secwatch.filing_event.v1"
accession: "0001193125-22-279724"
form_type: "8-K"
ticker: "SPRO"
cik: "0001701108"
company_name: "Spero Therapeutics, Inc."
filed_at: "2022-11-08T23:59:59+00:00"
generated_at: "2026-06-22T04:00:23.470126+00:00"
event_type: "other_material"
sentiment: "positive"
materiality_score: 0.9
calibrated_materiality_score: 0.9
confidence: "high"
source: SEC EDGAR
---

# Spero Therapeutics closes exclusive license agreement with GSK for tebipenem HBr

## Summary
- Received $66 million upfront payment from GSK under the exclusive license agreement.
- GSK affiliate purchased 7,450,000 shares of Spero common stock for approximately $9 million.
- Spero eligible for up to $525 million in development, sales, and commercial milestones plus tiered royalties.
- Spero will conduct a follow-up Phase 3 trial; GSK responsible for further development and commercialization outside Meiji Seika territories.
- GSK granted exclusive license to develop and commercialize tebipenem HBr in all territories except Japan and certain Asian countries.

## SEC filing metadata
- accession: 0001193125-22-279724
- form_type: 8-K
- ticker: SPRO
- cik: 0001701108
- company_name: Spero Therapeutics, Inc.
- filed_at: 2022-11-08T23:59:59+00:00
- event_type: other_material
- sentiment: positive
- materiality_score: 0.9
- calibrated_materiality_score: 0.9
- confidence: high
- sec_items: 8.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1701108/000119312522279724/0001193125-22-279724-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1701108/000119312522279724/d416179d8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001193125-22-279724
- JSON: https://secwatch.observer/filing/0001193125-22-279724.json
- Plain text: https://secwatch.observer/filing/0001193125-22-279724.txt

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