Merck Announces Positive Phase 3 Results for GARDASIL®9 in Preventing HPV Infections in Japanese Males Aged 16–26

MSD announced positive results from the Phase III V503-064 study of the nine-valent HPV vaccine Gardasil 9 in preventing HPV infection in Japanese males aged 16-26.

This trial was a double-blind, placebo-controlled clinical trial (n=1059) that evaluated the safety, tolerability, and efficacy of 3 doses of Gardasil 9 in helping 16-26-year-old Japanese males prevent HPV-related anogenital persistent infections. The primary endpoint of the study was the reduction in the incidence of HPV 6/11/16/18-related anogenital persistent infections by Gardasil 9 at 6 months follow-up, and the secondary endpoint was the reduction in the incidence of HPV 31/33/45/52/58-related anogenital persistent infections by Gardasil 9 at 6 months follow-up.

Results showed that the study met both primary and secondary endpoints. Compared with placebo, Gardasil 9 reduced the overall incidence of persistent infections related to 9 types of HPV-associated anogenital diseases.

Dr. Eliav Barr, Senior Vice President of Merck Research Laboratories, Head of Global Clinical Development, and Chief Medical Officer, stated: "A decade after Gardasil 9 was first approved, MSD continues to evaluate the vaccine’s preventive efficacy across broader populations and remains committed to helping prevent certain HPV-related cancers by improving its global accessibility. These data demonstrate the clinical effectiveness of Gardasil 9 in preventing persistent HPV-related anogenital infections in males, potentially making a significant impact on the global burden of certain HPV-related cancers and diseases."

MSD plans to share these data with regulatory agencies in Japan and other countries or regions, with the aim of further expanding the vaccine's scope of application.

Gardasil 9 was first approved for marketing in the United States in December 2014 and is currently the only available nine-valent HPV vaccine. In July 2020, the vaccine was approved for marketing in Japan under the trade name Silgard 9 and is currently only applicable to the female population.