---
schema_version: "secwatch.filing_event.v1"
accession: "0001140361-24-040755"
form_type: "8-K"
ticker: "BBIO"
cik: "0001743881"
company_name: "BridgeBio Pharma, Inc."
filed_at: "2024-09-11T23:59:59+00:00"
generated_at: "2026-05-31T05:27:36.863234+00:00"
event_type: "other_material"
sentiment: "negative"
materiality_score: 0.8
calibrated_materiality_score: 0.8
confidence: "high"
source: SEC EDGAR
---

# BridgeBio halts CAH gene therapy after Phase 1/2 shows cortisol production but not transformative; cuts budget $50M+

## Summary
- Phase 1/2 ADventure trial of BBP-631 in classic CAH: increased endogenous cortisol in all higher-dose patients (max change 6.6 µg/dL post-ACTH); well tolerated with no treatment-related SAEs.
- BBP-631 achieved durable transgene activity: 55-fold avg increase in 11-deoxycortisol at highest doses; ≥50% reduction in 17-OHP in majority of patients.
- Company discontinues BBP-631 development for CAH, citing data not meeting threshold for additional capital investment; budget cut >$50M.
- BridgeBio seeking partnership opportunities for BBP-631 or next-gen CAH gene therapies; est. >75,000 CAH cases in US+EU.
- CFO states reserving gene therapy for priority targets like Canavan disease; will work with FDA to accelerate Canavan therapy.

## SEC filing metadata
- accession: 0001140361-24-040755
- form_type: 8-K
- ticker: BBIO
- cik: 0001743881
- company_name: BridgeBio Pharma, Inc.
- filed_at: 2024-09-11T23:59:59+00:00
- event_type: other_material
- sentiment: negative
- materiality_score: 0.8
- calibrated_materiality_score: 0.8
- confidence: high
- sec_items: 8.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1743881/000114036124040755/0001140361-24-040755-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1743881/000114036124040755/ef20035749_8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001140361-24-040755
- JSON: https://secwatch.observer/filing/0001140361-24-040755.json
- Plain text: https://secwatch.observer/filing/0001140361-24-040755.txt

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