---
schema_version: "secwatch.filing_event.v1"
accession: "0001193125-26-097611"
form_type: "8-K"
ticker: "MBX"
cik: "0001776111"
company_name: "MBX Biosciences, Inc."
filed_at: "2026-03-09T23:59:59+00:00"
generated_at: "2026-05-15T18:03:16.371294+00:00"
event_type: "regulatory"
sentiment: "positive"
materiality_score: 0.8
calibrated_materiality_score: 0.8
confidence: "high"
source: SEC EDGAR
---

# MBX Biosciences successful End-of-Phase 2 FDA meeting; Phase 3 trial for canvuparatide in Q3 2026

## Summary
- Phase 3 double-blind placebo-controlled trial will enroll ~160 patients; 3:1 randomization, 4-week fixed 600 ug dose then 18-week titration, 4-week maintenance.
- Primary endpoint: proportion of participants achieving normal serum calcium and independence from conventional therapy at Week 26; open-label extension after.
- Canvuparatide granted Orphan Drug Designation by European Medicines Agency for chronic hypoparathyroidism.
- Company on track to initiate Phase 3 trial in Q3 2026 based on FDA feedback from End-of-Phase 2 meeting.

## SEC filing metadata
- accession: 0001193125-26-097611
- form_type: 8-K
- ticker: MBX
- cik: 0001776111
- company_name: MBX Biosciences, Inc.
- filed_at: 2026-03-09T23:59:59+00:00
- event_type: regulatory
- sentiment: positive
- materiality_score: 0.8
- calibrated_materiality_score: 0.8
- confidence: high
- sec_items: 7.01, 8.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1776111/000119312526097611/0001193125-26-097611-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1776111/000119312526097611/mbx-20260309.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001193125-26-097611
- JSON: https://secwatch.observer/filing/0001193125-26-097611.json
- Plain text: https://secwatch.observer/filing/0001193125-26-097611.txt

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