The company also said that the vaccine has shown 100% efficacy in preventing precancerous lesions due to cancer-causing virus types 16 and 18 and also provided substantial protection against infection caused by virus types 31 and 45.
These data show that virtually 100% of women in the study, 15-25 years of age, maintained high levels of antibodies against both virus types 16 and 18 at every time point for nearly six and half years. This signifies the longest duration of consistently high antibody levels demonstrated by a cervical cancer vaccine. Antibody levels remained several times higher than natural infection levels over the extended period of time.
The study also confirmed substantial cross-protection for nearly six and a half years against incident infection caused by virus types 45 and 31. Specifically, the vaccine showed 78% efficacy in preventing incident infection caused by virus type 45, and 60% efficacy in preventing incident infection caused by virus type 31.