XmAb657 / Xencor - LARVOL DELTA

XmAb657 (CD19 x CD3), a clinical-stage, potent, extended half-life B-cell depleting bispecific T-cell engager in development for patients with idiopathic inflammatory myopathies (IIM). (FinancialContent) - "In the fourth quarter of 2025, Xencor initiated a Phase 1 proof-of-concept study of XmAb657 for patients with IIM. We plan to: Provide an update on progress achieved in the Phase 1 study of XmAb657 in 2H26."

Trial status • Immunology • Inflammation • Myositis

A Phase 1 Open-label Study to Evaluate Safety in Healthy Participants and Participants With Idiopathic Inflammatory Myopathy (IIM) (clinicaltrials.gov) - P1 | N=27 | Not yet recruiting | Sponsor: Xencor, Inc.

First-in-human • New P1 trial • Myositis

XmAb657, a CD19 x CD3 T-Cell Engaging Bispecific Antibody for Autoimmune Disease (ACR Convergence 2025) - "XmAb657, a CD19 x CD3 bispecific antibody engineered for treatment of autoimmune disease, demonstrated potent in vitro activity and deep, durable depletion of circulating and tissue-resident B cells in cynomolgus monkeys after a single dose. Targeting CD19 may complement other B-lineage–directed approaches by extending depletion to a broader range of B cell subsets. These findings support the ongoing advancement of XmAb657 into first-in-human clinical studies."

Immunology • CD69 • IFNG • IL2RA

Upcoming Clinical Study Initiation Plans (Businesswire) - "XmAb657 (CD19 x CD3), a potent, extended half-life B-cell depleting bispecific T-cell engager for development in autoimmune disease. Xencor plans to initiate a first-in-human study in the second half of 2025; TL1A x IL23 Program: a bispecific antibody for dual targeting of important inflammatory pathways in autoimmune and inflammatory disease, while avoiding the complexities of dosing and formulary access for two separate TL1A and IL23 targeted drugs. Xencor anticipates selecting a lead candidate in 2025 and initiating first-in-human studies during 2026."

New trial • Pipeline update • Immunology • Inflammation