A single dose of human papillomavirus (HPV) vaccine would provide protection as effective as the two or three doses currently recommended in different countries.
At the end of 2014, the World Health Organization (WHO) recommended the administration of vaccines against human papillomavirus (HPV) for young girls from 9 years old, that is to say before the onset of sexual activity. “Vaccinating early would make it possible to use only two doses, which represents a significant saving for countries with modest incomes”, specified the Organization. And reduce the doses for the same effectiveness, this is precisely the message of a publication published in The Lancet Oncology this Wednesday.
Identical efficacy despite different doses
HPV viruses are found in 70% of cervical cancers. HPV 16 and 18 are the cause of condyloma and precancerous lesions which after several years can progress to cancers of the cervix but also to anal or throat cancers.
The analysis published in the Lancet by researchers from the University of New Mexico (United States) looked at the results of two large clinical trials: one carried out on 7,500 women in Costa Rica and the other on 18,500 women recruited in America , in Europe and Asia-Pacific. The authors conclude that a single dose of vaccine would provide protection as effective as the two or three doses currently recommended against HPV.
The follow-up of the young women four years after the injections shows, in the two trials, that the protection conferred by the Cervarix vaccine against infections by the HPV 16 and 18 viruses was approximately the same whether they had received one or three doses.
Data to be confirmed in larger cohorts
For the Dr Aimée R. Kreimer, from the American National Cancer Institute (NCI), “if the results of the study are confirmed, it could reduce the costs of immunizing young girls in the least developed countries of the world where more than 80% of cases occur. cervical cancer. “
Researchers at the University of New Mexico led by Cosette Wheeler conclude that “new studies will be needed to confirm their results with larger groups of women and over longer durations. “
Importantly, the study here only focused on the Cervarix vaccine. Another vaccine, Gardasil, is also widely used at present in the world and in particular in France where the authorities have recommended since 2014 two injections and no longer three as was the case previously.
Cancer of the cervix is now the 4th most common cancer in women worldwide, with an upsurge in developing countries.
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