One dose of GlaxoSmithKline's Cervarix may suffice

The recommended schedule for HPV vaccination is two or three doses, but some patients never make it back for all of the shots. This may cease to be a concern if future trials prove what scientists reported on Wednesday: A single dose of GlaxoSmithKline's ($GSK) Cervarix could work as well as the recommended two- or three-dose regimens at preventing the majority of cervical cancers.

Scientists compared data from two Phase III trials of the vaccine in young women, who received one, two or three doses of either Cervarix or a control vaccine. The results showed that protection from one dose is similar to the protection from three doses.

Dr. Diane Harper

"These exciting findings address the fact that nearly two-thirds of people who get HPV vaccines do not get all three doses in a timely manner," said Dr. Diane Harper of the University of Louisville School of Medicine, a co-author of the study, in a statement. "Knowing that Cervarix offers protection in one dose reassures public health agencies that they are not wasting money when most of their vaccines are given to those who never complete the three-dose series."

In addition to improving uptake, a one-dose schedule would reduce the cost of vaccinating patients, which could spur more countries to add an HPV vaccine to their routine schedule.

While Cervarix targets two strains of HPV--which cause about 70% of cervical cancers--a one-dose vaccine would have a leg up over Merck's ($MRK) Gardasil, which targets four strains. In December, the FDA approved Merck's follow-up, Gardasil 9, which protects against 9 strains of HPV. It has the potential to ward off 90% of cervical cancers, but only if vaccine uptake improves. Factors impeding uptake include lack of reimbursement for boys, sex-related stigma and the three-dose schedule.

- here's the University of Louisville statement

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