---
schema_version: "secwatch.filing_event.v1"
accession: "0001193125-26-268477"
form_type: "8-K"
ticker: "MBX"
cik: "0001776111"
company_name: "MBX Biosciences, Inc."
filed_at: "2026-06-12T11:05:58+00:00"
generated_at: "2026-06-12T11:10:11.331733+00:00"
event_type: "other_material"
sentiment: "positive"
materiality_score: 0.85
calibrated_materiality_score: 0.85
confidence: "high"
source: SEC EDGAR
---

# MBX Biosciences announces sustained one-year data for once-weekly canvuparatide in hypoparathyroidism

## Summary
- 57% of evaluable patients (31/54) achieved responder status at one year, comparable to 63% at 12 weeks in Phase 2 Avail trial.
- PK profile supports once-weekly dosing with peak-to-trough ratio of ~1.3 over one week, ensuring stable exposure.
- Mean eGFR increased from baseline at Week 12 and remained improved through one year; urine calcium decreased and stayed normal.
- Canvuparatide was well tolerated; no treatment-related serious adverse events; injection site reactions in 10% of OLE patients.
- Phase 3 pivotal trial remains on track to initiate in Q3 2026; 90% of OLE patients continued treatment at one year.

## SEC filing metadata
- accession: 0001193125-26-268477
- form_type: 8-K
- ticker: MBX
- cik: 0001776111
- company_name: MBX Biosciences, Inc.
- filed_at: 2026-06-12T11:05:58+00:00
- event_type: other_material
- sentiment: positive
- materiality_score: 0.85
- calibrated_materiality_score: 0.85
- confidence: high
- sec_items: 7.01, 8.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1776111/000119312526268477/0001193125-26-268477-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1776111/000119312526268477/mbx-20260612.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001193125-26-268477
- JSON: https://secwatch.observer/filing/0001193125-26-268477.json
- Plain text: https://secwatch.observer/filing/0001193125-26-268477.txt

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