Vaccinex, Inc. . announced that it has initiated a Phase 1 clinical trial to assess the safety, tolerability and pharmacokinetics of therapeutic antibody candidate VX15/2503 in patients with multiple sclerosis. VX15/2503 is a novel humanized monoclonal antibody targeting the multi-functional protein semaphorin 4D (SEMA4D), and represents the second clinical trial for this investigational drug.

Signaling cascades initiated by SEMA4D regulate activation and migration of inflammatory cells, inhibit remyelination, and disrupt endothelial tight junctions leading to breakdown of the blood-brain barrier. Each of these mechanisms is known to contribute to the severity and progression of neuroinflammatory/neurodegenerative diseases including multiple sclerosis. Studies in multiple animal models have shown that anti-SEMA4D antibody can successfully ameliorate disease severity.

It is particularly gratifying for Vaccinex to translate into the clinic the first therapeutic to target this important new class of regulatory molecules. Vaccinex is currently completing a parallel trial of VX15/2503 antibody in patients with solid tumors and plans to continue to advance studies of the therapeutic benefit of this unique and novel agent.