Visual abstract | Efficacy and safety of obexelimab in SLE: Results from a phase II study

Systemic lupus erythematosus (SLE) is a complex, heterogenous, chronic autoimmune disorder. The underlying mechanisms of SLE are driven by the enhanced activity and prolonged survival of B cells due to abnormalities in the B cell receptor (BCR). Several regulators, such as CD19 (B cell-exclusive surface protein) and CD32b (Fcγ receptor IIb [FcγRIIb]), impact BCR signaling. FcγRIIb activation plays a crucial role in suppressing autoimmunity by attenuating BCR signaling, leading to decreased B cell response to activating signals. Thus, targeting CD19 and FcγRIIb could serve as a potential treatment approach for SLE.

Obexelimab is an investigational, humanized, noncytolytic, monoclonal antibody. The antibody variable region of obexelimab exhibits a strong binding affinity to human CD19, while its Fc component binds to FcγRIIb, resulting in inhibition of B cells, plasmablasts and CD19+ plasma cells.

Merrill et al. recently published an article in Arthritis & Rheumatology_, on a phase II, proof-of-concept study (NCT02725515) evaluating the efficacy and safety of obexelimab in patients with SLE. We are pleased to summarize the key findings in our visual abstract below.