“This is an amazing result that bodes well for women's protection against cervical cancer,” she commented in an interview, explaining that “there is no wait time for memory cells to recognize and remanufacture antibodies with complete seropositivity and high antibody titers.”
The antibodies are abundant and waiting to neutralize an infection, she said.
Vaccine efficacy at 6.4 years for all HPV 16 and 18 end points was substantial at 97% for incident infection, 100% for 6-month persistent infection, and 100% for 12-month persistent infection. Vaccine efficacy also was 100% against cervical intraepithelial neoplasia grades 1 and higher (CIN1+) and 2 and higher (CIN2+) associated with HPV 16 and 18. There were no cases of CIN1+ or CIN2+ in the vaccinated group vs. 15 cases of CIN1+ and 9 cases of CIN2+ in the placebo group.
Dr. Harper noted that HPV types 16, 18, 45, and 31 make up more than 80% of squamous cell carcinomas and more than 90% of adenocarcinomas associated with HPV. Thus, the level of protection Cervarix provided in this study would provide “a significant possible reduction in disease.”
Cervarix, which would be a direct competitor to Merck & Co's Gardasil, is marketed in Europe and Australia, but it has not yet been approved in the United States. GlaxoSmithKline submitted a Biologics License Application to the Food and Drug Administration last year for the vaccine, but a decision on approval was delayed in December pending additional information from the company. The company anticipates approval this year.
Dr. Harper said she received financial support for conducting the GlaxoSmithKline phase II and III trials of Cervarix—and for conducting phase II and III clinical trials for Merck & Co.'s Gardasil. She also has received honoraria from both companies for consultations and speaking fees.
Sharon Worcester contributed to this article.
Overall, 26% of 14- to 19-year-olds wereinfectedwith at leastone STD. DR. FORHAN
This Month's Talk Back Question
How do you counsel sexually active teens in your practice to prevent sexually transmitted diseases?