---
schema_version: "secwatch.filing_event.v1"
accession: "0001326732-25-000082"
form_type: "8-K"
ticker: "XNCR"
cik: "0001326732"
company_name: "Xencor Inc"
filed_at: "2025-10-24T23:59:59+00:00"
generated_at: "2026-05-17T02:19:02.027952+00:00"
event_type: "other_material"
sentiment: "positive"
materiality_score: 0.75
calibrated_materiality_score: 0.75
confidence: "high"
source: SEC EDGAR
---

# Xencor reports 25% ORR for XmAb819 in ccRCC Phase 1; dose-expansion cohort selected

## Summary
- XmAb819 (ENPP3 x CD3) Phase 1: 25% ORR (5/20 PRs) and 70% DCR in target dose range in heavily pre-treated ccRCC.
- All 5 responders remain on treatment; 50% (10/20) of evaluable patients in target range remain on treatment as of Sep 19, 2025.
- Safety: CRS (Grade 3 in 4% with correct priming dose), no ICANS, no Grade 5 events; priming dose errors identified and remediated.
- First dose-expansion cohort enrolled; expect Phase 3 dose selection in 2026, pivotal study start in 2027.
- Early XmAb541 (CLDN6 x CD3) data also presented in ovarian, endometrial, and germ cell tumors.

## SEC filing metadata
- accession: 0001326732-25-000082
- form_type: 8-K
- ticker: XNCR
- cik: 0001326732
- company_name: Xencor Inc
- filed_at: 2025-10-24T23:59:59+00:00
- event_type: other_material
- sentiment: positive
- materiality_score: 0.75
- calibrated_materiality_score: 0.75
- confidence: high
- sec_items: 7.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1326732/000132673225000082/0001326732-25-000082-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1326732/000132673225000082/xncr-20251024.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001326732-25-000082
- JSON: https://secwatch.observer/filing/0001326732-25-000082.json
- Plain text: https://secwatch.observer/filing/0001326732-25-000082.txt

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