Vaccine dose 'may prevent cervical cancer'

A single dose of the HPV vaccine, instead of the recommended triple dose, could be enough to protect women against most cervical cancers, a new study says.

If the results are confirmed by further research, the development could be a game-changer for resource-poor countries, says Dr Julia Brotherton from the Victorian Cytology Service Registry.

And Joe Tooma, CEO of the Australian Cervical Cancer Foundation, says if one dose was shown to be effective there would be a far higher compliance rate by those being vaccinated.

The new research, published in the Lancet Oncology, analysed data from two previous trials involving 24,000 young women to see how much protection they got from one, two or three doses of the human papillomavirus (HPV) vaccine Cervarix.

Cervarix is similar to Gardasil, the most commonly used vaccine in Australia.

Cervarix targets HPV types 16 and 18, responsible for about 70 per cent of cervical cancers.

The vaccine was initially approved to be given in three doses over six months, but many countries are moving to two doses for adolescents.

The international researchers found "high vaccine efficacy" against HPV-16/18 infections regardless of the number of doses the women received.

The same result was found in a subgroup of women with no sign of HPV infection either before or at the time of first vaccination.

This suggested the results were relevant to "sexually-naive girls", aged 11 to 12, in the recommended age range for HPV vaccination, said co-lead author Dr Aimee Kreimer.

"Our findings question the number of HPV vaccine doses truly needed to protect the majority of women against cervical cancer, and suggest that a one-dose schedule should be further evaluated.

"If one dose is sufficient, it could reduce vaccination and administration costs as well as improve uptake.

"This is especially important in less developed regions of the world where more than 80 per cent of cervical cancer cases occur."