---
schema_version: "secwatch.filing_event.v1"
accession: "0000950170-25-112564"
form_type: "8-K"
ticker: "CYTK"
cik: "0001061983"
company_name: "CYTOKINETICS INC"
filed_at: "2025-09-02T23:59:59+00:00"
generated_at: "2026-05-17T08:43:04.477698+00:00"
event_type: "other_material"
sentiment: "positive"
materiality_score: 0.85
calibrated_materiality_score: 0.85
confidence: "high"
source: SEC EDGAR
---

# Aficamten superior to metoprolol in MAPLE-HCM Phase 3 trial; primary endpoint met (p<0.0001)

## Summary
- Least-squares mean pVO2 difference: +2.3 mL/kg/min (95% CI 1.5 to 3.1; p<0.0001) favoring aficamten.
- 51% of aficamten patients improved ≥1 NYHA class vs 26% on metoprolol (p<0.001).
- Aficamten reduced NT-proBNP by 81% vs metoprolol (p<0.0001); 1 patient had LVEF<50%.
- FDA PDUFA target action date for aficamten NDA is December 26, 2025.
- Results published simultaneously in The New England Journal of Medicine.

## SEC filing metadata
- accession: 0000950170-25-112564
- form_type: 8-K
- ticker: CYTK
- cik: 0001061983
- company_name: CYTOKINETICS INC
- filed_at: 2025-09-02T23:59:59+00:00
- event_type: other_material
- sentiment: positive
- materiality_score: 0.85
- calibrated_materiality_score: 0.85
- confidence: high
- sec_items: 8.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1061983/000095017025112564/0000950170-25-112564-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1061983/000095017025112564/cytk-20250830.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0000950170-25-112564
- JSON: https://secwatch.observer/filing/0000950170-25-112564.json
- Plain text: https://secwatch.observer/filing/0000950170-25-112564.txt

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