Safety and Immunogenicity Study of a 9-Valent Human Papillomavirus Vaccine Administered to 9-To-15 Year-Old Japanese Girls

Satoshi Iwata, Shinya Murata, Shi Rong Han, Akira Wakana, Miyuki Sawata, Yoshiyuki Tanaka

A 9-valent human papillomavirus (HPV 6/11/16/18/31/33/45/52/58) virus-like particle (VLP) vaccine (9vHPV) has been proven highly efficacious in preventing anogenital disease related with vaccine HPV types in a pivotal Phase III study in women aged 16 to 26 years. We report here the results of an open-label phase III study conducted to bridge the findings in women age 16 to 26 years to Japanese girls aged 9 to 15 years. All subjects (n = 100) received a 3-dose regimen of 9vHPV vaccine at day 1, month 2 and month 6. Anti-HPV serologic assays were performed at day 1, month 7, month 12, month 24 and month 30. At month 7 (4 weeks after dose 3), 100% of subjects seroconverted for each vaccine HPV type. Increases in geometric mean titers of anti-HPV 6/11/16/18/31/33/45/52/58 in girls were similar to those in Japanese women aged 16 to 26 years in the pivotal phase III study. Persistence of anti-HPV responses was observed through 2 years after dose 3. In addition, administration of 9vHPV vaccine was generally well tolerated in Japanese girls.