Plamotamab

November 2026: Xencor (NASDAQ: XNCR) gave a multi-program update. XmAb819 (ENPP3 x CD3) in advanced clear cell renal cell carcinoma showed at ESMO 2026 that, at the 400 mcg/kg IV dose, 5 of 11 efficacy-evaluable patients had confirmed partial responses (confirmed ORR 45.5%), with 1 additional unconfirmed PR (unconfirmed ORR 55%). Across combined expansion cohorts (n=68), treatment discontinuation due to related TEAEs was 5.9%; the company selected 400 mcg/kg IV as the proposed Phase 3 dose. Xencor plans FDA discussions on a potential accelerated approval pathway in 1H27, additional 400 mcg/kg and subcutaneous data in 1H27, and, subject to feedback, a global randomized Phase 3 trial versus tivozanib by year-end 2027.

Plamotamab (CD20 x CD3) in rheumatoid arthritis: early Phase 1b dose-escalation data were accepted for ACR Convergence in November 2026.

XmAb942 (anti-TL1A) in ulcerative colitis: the Phase 2b XENITH-UC study remains on track for a blinded interim analysis around year-end 2026 and primary endpoint analysis in 2H27.

XmAb412 (TL1A x IL23p19): first-in-human study is ongoing, with initial healthy participant data planned in 1H27.

Partnered catalysts: Amgen completed enrollment in the Phase 3 XALute study of xaluritamig in mCRPC; Astellas dosed the first patient in a Phase 3 ASP2138 study in first-line CLDN18.2-positive/HER2-negative gastric or GEJ adenocarcinoma; Zenas’ obexelimab BLA for IgG4-RD was accepted by FDA in August 2026.