---
schema_version: "secwatch.filing_event.v1"
accession: "0000950170-24-055046"
form_type: "8-K"
ticker: "CYTK"
cik: "0001061983"
company_name: "CYTOKINETICS INC"
filed_at: "2024-05-08T23:59:59+00:00"
generated_at: "2026-06-02T08:34:26.576830+00:00"
event_type: "other_material"
sentiment: "positive"
materiality_score: 0.55
calibrated_materiality_score: 0.55
confidence: "high"
source: SEC EDGAR
---

# Cytokinetics reports positive Phase 1 data for CK-586; Phase 2 in HFpEF expected Q4 2024

## Summary
- Phase 1 study of CK-586 met primary safety, tolerability, PK objectives; no serious adverse events observed.
- CK-586 is a novel cardiac myosin inhibitor for heart failure with preserved ejection fraction (HFpEF).
- Phase 2 trial in HFpEF patients expected to begin in Q4 2024; based on Phase 1 safety and PK profile.
- Echocardiography showed pharmacodynamics consistent with expectations; linear PK across doses 10-600 mg.
- Aficamten, company's other cardiac myosin inhibitor, supported mechanism in non-obstructive HCM.

## SEC filing metadata
- accession: 0000950170-24-055046
- form_type: 8-K
- ticker: CYTK
- cik: 0001061983
- company_name: CYTOKINETICS INC
- filed_at: 2024-05-08T23:59:59+00:00
- event_type: other_material
- sentiment: positive
- materiality_score: 0.55
- calibrated_materiality_score: 0.55
- confidence: high
- sec_items: 8.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1061983/000095017024055046/0000950170-24-055046-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1061983/000095017024055046/cytk-20240508.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0000950170-24-055046
- JSON: https://secwatch.observer/filing/0000950170-24-055046.json
- Plain text: https://secwatch.observer/filing/0000950170-24-055046.txt

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