Xencor Selects 400 mcg/kg as Phase 3 Dose for XmAb819 in Advanced Kidney Cancer

Xencor selected 400 mcg/kg as the proposed intravenous recommended Phase 3 dose for XmAb819 in advanced clear cell renal cell carcinoma, based on Phase 1 data presented at ESMO 2026. The clinical-stage biopharmaceutical company announced the dose selection on October 25, 2026, according to Business Wire.

Xencor's XmAb819 Phase 1 Dose Selection

Xencor presented updated Phase 1 results for XmAb819, an ENPP3 x CD3 T-cell engaging bispecific antibody, in patients with advanced ccRCC. Sumanta Pal, a professor and vice chair of academic affairs at City of Hope Comprehensive Cancer Center, presented the data in a proffered paper oral presentation at the European Society for Medical Oncology Congress 2026 in Madrid, Spain.

As of a September 1, 2026 data-cut, the study enrolled 119 patients across 11 intravenous target dose levels. The 400 mcg/kg expansion cohort reported a 45.5% confirmed objective response rate and an 82% 6-month progression-free survival Kaplan-Meier estimate. Xencor said the 400 mcg/kg cohort showed 45.5% confirmed response and 82% 6-month PFS.

"We plan to initiate a potential registration-enabling study next year," said Bassil Dahiyat, president and chief executive officer at Xencor. "With cash runway into 2029, we are well positioned to continue to pursue an accelerated pace of clinical development across our portfolios in oncology and autoimmune disease."

Xencor's Cash and Partnership Figures

Xencor is a clinical-stage biopharmaceutical company that engineers monoclonal antibody therapeutics using its XmAb Fc domain platform for cancer and autoimmune diseases, according to akta.pro company records. The same records list cash and cash equivalents of $610.8 million at the end of 2025, expected to fund operations into mid-2028, and full-year 2025 revenue of $125.6 million, up from $110.5 million in 2024.

Xencor's Earlier 2026 Milestones

Xencor closed a public offering of 8,093,712 shares at $18.00 per share in October 2026, raising gross proceeds of approximately $201.3 million before underwriting discounts and expenses, according to FinancialContent Business Page. In September 2026, Xencor presented at the 12th Annual Cantor Fitzgerald Global Healthcare Conference, outlining its shift to late-stage development with XmAb819 in renal cell carcinoma as the key program, according to Investing.com.

Xencor's Planned FDA Discussions

Xencor plans to discuss a potential accelerated approval pathway with the FDA in key ccRCC patient subgroups in the first half of 2027. The company also plans a global randomized study of monotherapy XmAb819 compared to tivozanib in a post PD-(L)1 and VEGFR TKI ccRCC patient population, and will host a webcast on October 26 at 7:00 a.m. ET.