Efficacy of human papillomavirus 16/18 AS04-adjuvanted vaccine in Japanese women aged 20 to 25 years: interim analysis of a phase 2 double-blind, randomized, controlled trial.
BACKGROUND
A phase 2 double-blind, controlled, randomized multicenter study with human papillomavirus (HPV)-16/18 AS04-adjuvanted vaccine is ongoing in healthy Japanese women aged 20 to 25 years. We assessed the vaccine efficacy in the event-triggered analysis.


METHODS
Japanese women aged 20 to 25 years were randomly assigned to receive either HPV-16/18 AS04-adjuvanted (n = 519) or hepatitis A (n = 521) vaccine at 0, 1, and 6 months. The women were assessed for virological and cytological end points associated with HPV-16/18 in cervical specimens and for the vaccine safety and immunogenicity.


RESULTS
The mean length of follow-up for women in the primary analysis for efficacy at the time of a prespecified event-triggered interim analysis was 13.6 months after the first vaccination. Vaccine efficacy against HPV-16/18 persistent infections (6-month definition) in the according-to-protocol cohort for efficacy was 100% (99% confidence interval, 20.5-100, P = 0.0037). At 6 months after the third dose of vaccine, geometric mean titers against HPV-16 and HPV-18 were 2899.3 and 1352.2 enzyme-linked immunosorbent assay units per milliliter, respectively, that is, 97- and 60-fold higher than geometric mean titers observed after natural infection. There were no clinically meaningful differences in safety between the HPV and control group.


CONCLUSIONS
The HPV-16/18 AS04-adjuvanted vaccine was as efficacious in Japan as in other countries and was generally safe and highly immunogenic in Japanese women.
Konno
Ryo
R
Department of Obstetrics and Gynecology, Jichi Medical University, Saitama Medical Center, Omiya-ku, Saitama, Saitama. kryo772007@yahoo.co.jp
Tamura
Shinobu
S
Dobbelaere
Kurt
K
Yoshikawa
Hiroyuki
H
D000328:Adult; D044466:Asian People; D004311:Double-Blind Method; D005260:Female; D005500:Follow-Up Studies; D052162:Human papillomavirus 16 / Q000302:isolation & purification*; D052161:Human papillomavirus 18 / Q000302:isolation & purification*; D006801:Humans; D009367:Neoplasm Staging; D030361:Papillomavirus Infections / Q000473:pathology / Q000517:prevention & control* / Q000821:virology; D053918:Papillomavirus Vaccines / Q000008:administration & dosage*; D015996:Survival Rate; D016896:Treatment Outcome; D002583:Uterine Cervical Neoplasms / Q000473:pathology / Q000517:prevention & control* / Q000821:virology; D014626:Vaginal Smears; D055815:Young Adult; D002578:Uterine Cervical Dysplasia / Q000473:pathology / Q000517:prevention & control* / Q000821:virology
D053918:Papillomavirus Vaccines