---
schema_version: "secwatch.filing_event.v1"
accession: "0002007919-26-000020"
form_type: "8-K"
ticker: "INBX"
cik: "0002007919"
company_name: "Inhibrx Biosciences, Inc."
filed_at: "2026-05-11T20:02:50+00:00"
generated_at: "2026-05-11T22:57:08.127474+00:00"
event_type: "other_material"
sentiment: "positive"
materiality_score: 0.8
calibrated_materiality_score: 0.8
confidence: "high"
source: SEC EDGAR
---

# Inhibrx: INBRX-106 + pembro achieves 44% ORR vs 21.4% in HNSCC Phase 2

## Summary
- Confirmed ORR 44.0% (11/25) for combo vs 21.4% (6/28) for pembro alone; absolute increase 22.6%.
- Three complete responses in combo arm vs zero in control; deeper tumor reductions overall.
- Up to 15-fold increase in CD8+ and CD4+ T-cell proliferation in combo arm (vs up to 2.5-fold).
- No treatment-related deaths; most common AEs: rash, diarrhea, fatigue, infusion reactions.
- Phase 3 HexAgon start Q3 2026; perioperative NSCLC study later this quarter; metastatic NSCLC in 2027.

## SEC filing metadata
- accession: 0002007919-26-000020
- form_type: 8-K
- ticker: INBX
- cik: 0002007919
- company_name: Inhibrx Biosciences, Inc.
- filed_at: 2026-05-11T20:02:50+00:00
- event_type: other_material
- sentiment: positive
- materiality_score: 0.8
- calibrated_materiality_score: 0.8
- confidence: high
- sec_items: 7.01, 8.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/2007919/000200791926000020/0002007919-26-000020-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/2007919/000200791926000020/inhibrx-20260511.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0002007919-26-000020
- JSON: https://secwatch.observer/filing/0002007919-26-000020.json
- Plain text: https://secwatch.observer/filing/0002007919-26-000020.txt

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