The efficacy of the quadrivalent human papillomavirus vaccine for the prevention of lesions in the anogenital region
The use of a quadrivalent vaccine against types 6, 11, 16 and 18 of the human papillomavirus in young women leads to a significant decrease in the overall frequency of development of lesions in the anogenital region with these types of virus and lesions of the cervix.
Papillomavirus infection is one of the most common sexually transmitted infections in the world and is the leading cause of cervical cancer. In 2006, in a number of countries, including USA, the first vaccine against this infection (Gardasil, Merck & Company Inc.) was registered, which is a quadrivalent recombinant vaccine against 6, 11, 16 and 18 types of virus human papilloma (HPV).
A randomized, double-blind, placebo-controlled phase III clinical trial by S.M. Garland et al. (Australia), was an evaluation of the effectiveness of this vaccine in the prevention of lesions of the anogenital region caused by 6, 11, 16 and 18 types of virus. The study involved 5455 women aged 16 to 24, of whom 2723 received a vaccine and 2732 - a placebo according to the standard schedule (repeated administration after 2 and 6 months from the time of the primary vaccination).
2261 (83%) vaccinated women and 2279 (83%) women in the control group were followed up for follow-up (on average 3 years from the time the first dose of the test drug was administered) in relation with the development of lesions of the vulvar, vaginal and perianal regions, in relation to cervical lesions - 2241 (82%) and 2258 (83%) women, respectively. At the same time, the effectiveness of vaccination, which is understood as the absence of the aforementioned types of wart lesions associated with HPV infection in the anogenital region, intraepithelial neoplasia, and cancer of the vulva and vagina, intraepithelial neoplasia, adenocarcinoma in situ or cervical cancer, in women who were not infected with HPV during the examination 1 month after the introduction of the third dose of the vaccine, it was 100%.
When analyzing the patient population to treat, including HPV-infected women, both vaccine and non-vaccine type, vaccinated women showed a decrease in the incidence of any lesion of the vulva, vagina and of the perianal region, regardless of the type of HPV that caused it. 34% (95% confidence interval (CI) 15-49) and the incidence of cervical lesions, regardless of the type of virus that caused them, 20% (95% CI 8-31).
Another randomized, double-blind, placebo-controlled, phase III clinical trial (FUTURE II) evaluated the efficacy of the above vaccine in preventing cervical lesions at high risk of malignancy caused by 16 and 18 types of virus. The work included data from 10,565 women aged 15 to 26 who received a vaccine (n = 5305) or a placebo (n = 5,260) according to the standard schedule.
According to the results, the effectiveness of vaccination for the prevention of cervical lesions, such as grade 2-3 cervical intraepithelial neoplasia, adenocarcinoma in situ or cancer associated with infection by types 16 and 18 of the virus, was 98% (95.89% confidence interval (CI)) 86-100) when analyzed in a population of patients who did not have HPV types 16 and 18 infection within one month following administration of 3 doses of the study drug, and 44% (95% CI 26-58) when analyzed in patients to be treated (regardless of availability or infection with HPV tsutstviya). In general, the vaccine efficacy estimated to prevent the development of cervical lesions at high risk of malignancy, regardless of the type of HPV which caused them in the patient population to be treated, reached 17% (95% CI 1- 31).
Thus, the use of a quadrivalent vaccine against types 6, 11, 16 and 18 of the human papillomavirus in young women leads to a significant decrease in the overall frequency of development of lesions in the anogenital region with these types of virus, as well than lesions of the cervix with a high risk of malignancy.