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HPV immunisation for older women too? The vaccine to protect against human papillomavirus (HPV; e.g. GARDASIL) is licensed for girls and women aged 9 to 26 years, but is primarily recommended for girls aged around eleven to twelve who have not yet had sexual contact. "HPV immunisation also protects the cervix of older women" reads the headline in Ärzte Zeitung to mark the publication of a study on the benefit of GARDASIL in women aged 24 to 45 (Ärzte Ztg. dated 4 June 2009). The article deals with an interim analysis after 2.2 years' follow-up. The study included 3,819 women without genital warts or diseases, without a history of surgical operations in the cervical region and without a cervical biopsy in the previous five years. According to the analysis, the HPV vaccine protects women who, up to completion of the basic immunisation, were not infected with the analysed HPV types contained in the vaccine (per-protocol population) against infections lasting at least six months as well as diseases of the cervix and external genitalia caused by these HPV types (two primary collective endpoints: efficacy against HPV 6 , 11 , 16 or 18 associated "events" 90.5%; 95% confidence interval [CI] 73.7 - 97.5; efficacy against HPV-16- or 18-associated "events" 83.1%; 95% CI 50.6 - 95.8).* Hence a combined endpoint is being analysed which, in terms of infections lasting at least six months and low-grade dysplasias, contains "events" that are not relevant because of their strong tendency to clear spontaneously and cannot be interpreted as precancerous stages. Moreover, they are a far common occurrence than more serious cell changes. The established advantages of immunisation are primarily based on a decrease in infections (MUÑOZ, N. et al.: Lancet 2009; 373: 1949-57). It is not mentioned in the present article that no benefit can be demonstrated against higher-grade cervical dysplasias (CIN2+). This can be concluded from an evaluation which was presented in June 2008 at a meeting of the US health authority (protective effect 75.2%; 95% CI -150.6 to 99.5; a-t 2008; 39: 87). In view of the fact that girls and young women are - currently - the intended target group for immunisation, it still seems understandable to confine the primary analysis to women who are not yet infected with the HPV types contained in the vaccine. However, this method, which requires multiple testing for HPV, is entirely impractical for the women being studied here. Only the results of the intention-to-treat analyses are relevant to everyday practice: these include all the randomised women who have received at least one immunisation. A significant effect in this group can only be detected for events that are associated with HPV 6, 11, 16 or 18 (effectiveness 30.9%; 95% CI 11.1 - 46.5). The HPV-16- or HPV-18-associated events relevant to the development of precancerous lesions and carcinomas of the cervix are not significantly influenced (22.6%; 95% CI -2.9 - 41.9). Finally it emerges from the current article that the study has now been completed and fully analysed. It is hard to understand why the authors are still only publishing out-of-date results. -Ed.
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