Vaccinex Qualifies Positive Data for SIGNAL-AD Phase 1b/2 trial of Pepinemab in Alzheimer’s

 Vaccinex, Inc. (Nasdaq: VCNX), a clinical-stage biotechnology company pioneering treatment of Alzheimer’s disease (AD) with anti-Semaphorin 4D (SEMA4D) antibody, today announced positive results of its early stage SIGNAL-AD clinical trial of pepinemab antibody in AD. Topline results were presented by Eric Siemers, MD, Principal Investigator of the SIGNAL-AD trial, at the Alzheimer’s Association International Conference in Philadelphia.

The clinical trial met its designated primary endpoint of safety by indicating that pepinemab is well-tolerated by patients with AD. No Serious Treatment Emergent Adverse Events (TEAE) Related to Treatment were reported by investigators at any of the 16 clinical sites that participated in this study. The only TEAE leading to discontinuation in the entire trial was in the placebo group. Vaccinex had previously reported that pepinemab (VX15/2503) was well-tolerated by patients with Huntington’s disease (HD) and multiple sclerosis (MS).

An important secondary endpoint of the study was to determine whether pepinemab prevents decline in brain metabolic activity consistent with blocking astrocyte reactivity as evidenced by an increase in FDG-PET imaging signal in a major brain region known to be affected by disease progression. This was determined over the course of 12-months treatment with pepinemab relative to placebo. We report that pepinemab treatment resulted in a statistically significant increase (p=0.0297) in FDG-PET signal in the medial temporal cortex of patients with Mild Cognitive Impairment (MCI) due to AD. The medial temporal region of brain includes hippocampus and entorhinal cortex known to be affected during early disease progression in many patients with MCI. A similar significant result of pepinemab treatment on brain metabolic activity was previously shown in our phase 2 study of HD which we believe highlights mechanistic similarities in the pathology of these two neurodegenerative diseases.

Although the present study was not sufficiently powered to detect cognitive effects or changes in some additional secondary endpoints with statistical significance, we previously reported that, in a larger study that enrolled approximately 90 HD patients/arm with early symptoms of cognitive deficits, seemingly similar to MCI in AD, pepinemab treatment improved performance on key cognitive and psychological measures.

https://www.globenewswire.com/news-release/2024/07/31/2921918/34858/en/Vaccinex-Reports-Positive-Data-for-SIGNAL-AD-Phase-1b-2-trial-of-Pepinemab-in-Alzheimer-s-Disease.html