US pharmaceutical group Merck has announced an experimental vaccine it says is 100% effective against the most common form of cervical cancer.
The results of a wide-scale study of the drug were presented for the first time yesterday at the annual meeting of the European Society of Pediatric Infectious Diseases in Spain.
It is the first trial to evaluate immune responses and tolerability among young adolescents aged ten to 15.
The genetically engineered vaccine stops cancer by blocking two sexually transmitted diseases, HPV16 and HPV18, which together are blamed for 70% of this kind of tumor.
Over the two and a half years of follow-up after vaccination, Gardasil reduced the combined incidence of persistent infection from four different HPVs and related genital disease, including new cervical pre-cancers and genital warts, by 90% when compared with women who had taken no vaccine.
The study, a phase two clinical trial, was done on 12,167 sexually active girls and women aged 16-26 in the US and 12 other countries who were not already infected with the two viruses.
Phase III clinical trials to evaluate the safety and efficacy of Gardasil are currently under way, with over 25,000 participants enrolled worldwide.
