---
schema_version: "secwatch.filing_event.v1"
accession: "0001104659-23-128988"
form_type: "8-K"
ticker: "MIST"
cik: "0001408443"
company_name: "Milestone Pharmaceuticals Inc."
filed_at: "2023-12-26T23:59:59+00:00"
generated_at: "2026-06-07T07:16:24.201115+00:00"
event_type: "regulatory"
sentiment: "negative"
materiality_score: 0.75
calibrated_materiality_score: 0.75
confidence: "high"
source: SEC EDGAR
---

# Milestone Pharma receives FDA refusal to file for etripamil NDA for PSVT

## Summary
- FDA issued Refusal to File letter for etripamil NDA submitted October 2023.
- FDA cited insufficient completeness, requested clarification on adverse event timing in Phase 3.
- FDA did not express concerns about nature or severity of adverse events.
- Milestone will seek meeting with FDA to address issues and agree on path forward.
- Etripamil is a self-administered nasal spray for paroxysmal supraventricular tachycardia.

## SEC filing metadata
- accession: 0001104659-23-128988
- form_type: 8-K
- ticker: MIST
- cik: 0001408443
- company_name: Milestone Pharmaceuticals Inc.
- filed_at: 2023-12-26T23:59:59+00:00
- event_type: regulatory
- sentiment: negative
- materiality_score: 0.75
- calibrated_materiality_score: 0.75
- confidence: high
- sec_items: 8.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1408443/000110465923128988/0001104659-23-128988-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1408443/000110465923128988/tm2333688d1_8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001104659-23-128988
- JSON: https://secwatch.observer/filing/0001104659-23-128988.json
- Plain text: https://secwatch.observer/filing/0001104659-23-128988.txt

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