ROCHESTER, N.Y., Dec. 9, 2014 /PRNewswire/ — Vaccinex, Inc. today announced the successful completion of a multicenter Phase 1, multiple ascending dose clinical trial of VX15/2503 anti-Semaphorin 4D (SEMA4D) antibody in 42 adult patients with advanced, refractory solid tumors. VX15/2503 is a first in class, monoclonal antibody discovered, characterized, and tested successfully by Vaccinex in preclinical cancer models. In total, 459 doses of VX15/2503 were administered to patients, ranging in concentration from 0.3 to 20 mg/kg. Patient tumors were assessed by RECIST 1.1 at approximately 8 week intervals. VX15/2503 was found to be well tolerated at dose levels up to 20 mg/kg. Anti-tumor response was examined as an exploratory objective of the study. Seventeen of 42 patients at all dose levels exhibited stable disease for at least 8 weeks and nine patients showed stable disease for 16 weeks or more. Patients with the longest stable disease, from 48 to 55 weeks, included patients with colorectal and breast carcinomas, and a papillary thyroid patient who had a partial response as assessed by RECIST and stable disease for at least 6 months following cessation of treatment at 48 weeks. Detailed study results will be published in a peer reviewed medical journal.

Vaccinex, Inc., based in Rochester, New York, is a privately held clinical-stage biotechnology company engaged in the discovery and development of human therapeutic monoclonal antibodies to treat cancer and neurodegenerative diseases, including multiple sclerosis and Huntington’s disease. Vaccinex utilizes its proprietary ActivMAb® Antibody Discovery Technology for rapid, mammalian cell-based antibody selection to build its antibody pipeline and in service to its biopharmaceutical partners. Compared to other selection technologies, ActivMAb® combines the advantages of rapid and sensitive selection by virus panning and cell sorting in one technology, with intrinsic selection of antibodies that are efficiently expressed and stable in mammalian cells. For more information and to contact Vaccinex, visit www.vaccinex.com.