HPV Vaccine Shows Promise in Phase III Trial
Immunogenicity non-inferior to that of Gardasil (November 4)
In a pivotal phase III efficacy study, an investigational nine-valent human papillomavirus (HPV) vaccine (V503, Merck) prevented approximately 97% of cervical, vaginal, and vulvar precancers caused by HPV types 31, 33, 45, 52, and 58. The vaccine also generated immune responses to HPV types 6, 11, 16, and 18 that were non-inferior to those generated by Gardasil (human papillomavirus quadrivalent [types 6, 11, 16, and 18] vaccine, recombinant, Merck).
The new data, along with results from two other phase III studies, will be presented Nov. 5 at the European Research Organization on Genital Infection and Neoplasia (EUROGIN) Congress in Florence, Italy.
The pivotal phase III trial evaluated the efficacy, safety, and immunogenicity of V503 (n = 7,099) compared with Gardasil (n = 7,105) in women 16 to 26 years old. The primary efficacy analysis was conducted in those who received all three doses of vaccine within 1 year, who were not infected with the relevant HPV types at enrollment, and who remained free of infection with the relevant HPV types through month 7 (per-protocol population). The key results were as follows:
- 96.7% reduction (95% confidence interval [CI], 80.9–99.8) in the combined incidence of high-grade cervical/vulvar/vaginal disease (cervical intraepithelial neoplasia [CIN] 2/3+; vulvar intraepithelial neoplasia [VIN],) 2/3+; and vaginal intraepithelial neoplasia [VaIN] 2/3+) caused by HPV types 31, 33, 45, 52, and 58 (one case in the group that received V503 vs. 30 cases in the group that received Gardasil).
- 97.1% reduction (95% CI, 91.8–99.2) in the combined incidence of cervical/vulvar/vaginal disease of any grade (all CIN, VIN, and VaIN) caused by HPV types 31, 33, 45, 52, and 58 (three cases in the V503 group vs. 103 cases in the Gardasil group).
- 96.0% efficacy (95% CI, 94.4–97.2) against 6-month persistent HPV infection with HPV types 31, 33, 45, 52, and 58 (35 cases in the V503 vs. 810 cases in the Gardasil group).
Source: Merck; November 4, 2013.