Plamotamab (CD20 x CD3)
CD20 x CD3 bispecific T-cell engager to be evaluated in patients with multi-drug resistant rheumatoid arthritis
Plamotamab (CD20 x CD3) is a B-cell depleting bispecific T-cell engager in development for patients with rheumatoid arthritis (RA). Xencor is conducting a Phase 1b proof-of-concept study of plamotamab in patients with RA who have progressed through prior standard-of-care treatment.
Xencor previously completed a Phase 1 clinical study of plamotamab in hematologic cancers, completing enrollment in late 2023. Results from the study showed favorable tolerability and comparable preliminary efficacy data, when cross compared to results from studies of a competitor molecule within the class, with similar patient baseline characteristics. Based on these clinical outcomes, significant B-cell depletion observed in preclinical studies, and the emergent biology supportive of B-cell targeted T cell engagers for the treatment of patients with autoimmune diseases, Xencor plans to evaluate plamotamab in MDR-RA, in which patients progressed through two prior lines of therapy.