(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, M.D., 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 (0.3, 1, and 3 mg 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.