---
schema_version: "secwatch.filing_event.v1"
accession: "0001193125-23-276030"
form_type: "8-K"
ticker: "SPRO"
cik: "0001701108"
company_name: "Spero Therapeutics, Inc."
filed_at: "2023-11-13T23:59:59+00:00"
generated_at: "2026-06-08T05:16:07.785078+00:00"
event_type: "earnings"
sentiment: "positive"
materiality_score: 0.7
calibrated_materiality_score: 0.7
confidence: "high"
source: SEC EDGAR
---

# Spero Q3 net loss $3.2M, revenue $25.5M on $30M GSK milestone; FDA SPA for Phase 3 tebipenem HBr

## Summary
- Net loss $3.2M ($0.06/shr) vs $11.7M loss ($0.33/shr) YoY; revenue $25.5M vs $2.0M YoY driven by $23.2M GSK collaboration revenue.
- Cash $93.8M expected to fund operations into H2 2025; received $30M development milestone from GSK under tebipenem HBr license.
- FDA granted Special Protocol Assessment for Phase 3 PIVOT-PO trial of oral tebipenem HBr in cUTI/AP; enrollment start expected Q4 2023.
- Phase 2a SPR720 trial for NTM-PD ongoing; topline data expected H2 2024. IND for SPR206 planned Q4 2023.
- Sath Shukla appointed President and CEO (Aug 1); Esther Rajavelu named CFO and CBO (Nov 1), replacing prior CFO role.

## SEC filing metadata
- accession: 0001193125-23-276030
- form_type: 8-K
- ticker: SPRO
- cik: 0001701108
- company_name: Spero Therapeutics, Inc.
- filed_at: 2023-11-13T23:59:59+00:00
- event_type: earnings
- sentiment: positive
- materiality_score: 0.7
- calibrated_materiality_score: 0.7
- confidence: high
- sec_items: 2.02, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1701108/000119312523276030/0001193125-23-276030-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1701108/000119312523276030/d572144d8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001193125-23-276030
- JSON: https://secwatch.observer/filing/0001193125-23-276030.json
- Plain text: https://secwatch.observer/filing/0001193125-23-276030.txt

## Key facts
- Earnings Releases
  Spero Therapeutics, Inc. reported financial results for the third quarter ended September 30, 2023.
  - Period: the third quarter ended September 30, 2023
  - Result: reported results
  source text: On November 13, 2023, Spero Therapeutics, Inc. (the “Company”) issued a press release announcing its results for the third quarter ended September 30, 2023.
  evidence_url: https://www.sec.gov/Archives/edgar/data/1701108/000119312523276030/0001193125-23-276030-index.htm

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