---
schema_version: "secwatch.filing_event.v1"
accession: "0001193125-22-017722"
form_type: "8-K"
ticker: "VCNX"
cik: "0001205922"
company_name: "VACCINEX, INC."
filed_at: "2022-01-26T23:59:59+00:00"
generated_at: "2026-06-27T15:21:14.027478+00:00"
event_type: "other_material"
sentiment: "positive"
materiality_score: 0.7
calibrated_materiality_score: 0.7
confidence: "high"
source: SEC EDGAR
---

# Vaccinex reports 2 complete responses in first 3 patients in Phase 1b KEYNOTE-B84 study for HNSCC

## Summary
- Two of three patients in Phase 1b safety segment achieved complete responses per RECIST v1.1.
- Both responders had low PD-L1 expression (CPS<20); HPV-negative status.
- Third patient had clinical progression and withdrew before week 9; SAEs attributed to pre-existing condition.
- Expansion phase now open; will enroll up to 62 additional patients across 18 US sites.
- Data safety monitoring board confirmed pepinemab (20 mg/kg Q3W) + KEYTRUDA (200 mg Q3W) well-tolerated.

## SEC filing metadata
- accession: 0001193125-22-017722
- form_type: 8-K
- ticker: VCNX
- cik: 0001205922
- company_name: VACCINEX, INC.
- filed_at: 2022-01-26T23:59:59+00:00
- event_type: other_material
- sentiment: positive
- materiality_score: 0.7
- calibrated_materiality_score: 0.7
- confidence: high
- sec_items: 8.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1205922/000119312522017722/0001193125-22-017722-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1205922/000119312522017722/d252591d8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001193125-22-017722
- JSON: https://secwatch.observer/filing/0001193125-22-017722.json
- Plain text: https://secwatch.observer/filing/0001193125-22-017722.txt

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