(HealthDay News) – A new candidate vaccine designed to prevent cervical dysplasia and cancer in women already infected with human papillomavirus (HPV) serotypes 16 and 18 is well tolerated and induces a robust immune response, according to a Phase 1 study published in the Oct 10 issue of Science Translational Medicine.
Mark L Bagarazzi, MD, from Inovio Pharmaceuticals Inc in Blue Bell, PA, and colleagues investigated the safety and efficacy of a therapeutic highly engineered plasmid DNA-based cervical cancer vaccine, VGX-3100, targeting HPV 16 and 18 in 18 women who had been previously treated for cervical intraepithelial neoplasia Grade 2 or 3.
The researchers found that VGX-3100 was well tolerated at the doses tested (0.3mg, 1mg, and 3mg per plasmid), with no dose-limiting toxicity observed. Interferon-gamma levels were highest at the highest vaccine dose given. At all doses, VGX-3100 induced functional HPV-specific CD8+ T cells that efficiently loaded granzyme B and perforin and demonstrated full cytolytic functionality.
“These data indicate that VGX-3100 is capable of driving robust immune responses to antigens from high-risk HPV serotypes and could contribute to elimination of HPV-infected cells and subsequent regression of the dysplastic process,” Bagarazzi and colleagues conclude.
The study was sponsored by Inovio Pharmaceuticals; many authors are employees of the company. One author disclosed financial ties to the pharmaceutical industry.