---
schema_version: "secwatch.filing_event.v1"
accession: "0000950170-21-002075"
form_type: "8-K"
ticker: "CMPX"
cik: "0001738021"
company_name: "Compass Therapeutics, Inc."
filed_at: "2021-10-08T23:59:59+00:00"
generated_at: "2026-06-28T21:56:59.204067+00:00"
event_type: "other_material"
sentiment: "positive"
materiality_score: 0.6
calibrated_materiality_score: 0.6
confidence: "high"
source: SEC EDGAR
---

# Compass Therapeutics reports CTX-009 Phase 1 data: 19% ORR at RP2D in heavily pre-treated tumors

## Summary
- CTX-009 monotherapy achieved 19% ORR (3/16) at RP2D (10.0-12.5 mg/kg) and 69% DCR.
- Across all doses, ORR was 8% (4 partial responses) and DCR was 62% in heavily pre-treated patients (median 3 prior lines).
- Treatment well tolerated; no dose-limiting toxicities; hypertension in 38% (17/45), 7 Grade 3.
- 94% of colorectal and 58% of gastric patients had prior anti-VEGF therapy (bevacizumab/ramucirumab).
- Phase 1b combo and Phase 2 studies underway; Compass holds global rights except S. Korea and China.

## SEC filing metadata
- accession: 0000950170-21-002075
- form_type: 8-K
- ticker: CMPX
- cik: 0001738021
- company_name: Compass Therapeutics, Inc.
- filed_at: 2021-10-08T23:59:59+00:00
- event_type: other_material
- sentiment: positive
- materiality_score: 0.6
- calibrated_materiality_score: 0.6
- confidence: high
- sec_items: 8.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1738021/000095017021002075/0000950170-21-002075-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1738021/000095017021002075/cmpx-20211008.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0000950170-21-002075
- JSON: https://secwatch.observer/filing/0000950170-21-002075.json
- Plain text: https://secwatch.observer/filing/0000950170-21-002075.txt

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