HPV vax effective with fewer doses

YOUNG women not receiving all three doses of the bivalent HPV vaccine may nevertheless be protected against infection, a study suggests.

A trial found little difference in incidence of HPV 16 or 18 infection among 18- to 25-year-old women four years after vaccination where many had skipped one or even two doses of Cervarix.

Vaccine efficacy was 80.9% among 2957 women who received all three doses, 84.1% among 422 women who received two, and 100% (no infections) in 196 women who had just one dose, the researchers found.

The trial in Costa Rica, funded by the US National Institutes of Health and supported by GSK, included controls receiving hepatitis A vaccine.

The data “suggests that two doses of HPV 16/18 vaccine, and maybe even one dose, are as protective as three doses” though it was “not known whether the three-dose regimen might provide longer duration of protection or more cross-protection”, the researchers said