The cervical cancer vaccine study resultsThe double-blind study randomly assigned 2,392 women between 16 and 23 years old to receive three doses of placebo or an HPV-16 virus-like particle vaccine, and followed them for approximately 17 months.
The primary end-point was persistent HPV-16 infection, defined as the detection of HPV-16 in samples at two or more visits.
In the vaccine group, 99.7% developed anti-bodies to the virus.
In the placebo group, the incidence of persistent HPV-16 infection was 3.8 per 100 woman-years compared to 0 in the vaccine group.
All nine cases of HPV-16related CIN occurred among placebo recipients.
Reference: NEJM 2002; 347:1645-51