Two doses of HPV vaccine as good as three, study shows

According to data from the National Cancer Institute's Costa Rica Vaccine Trial, two does of the human papillomavirus vaccine may offer as much protection against cervical cancer as the three dose regimen currently being used.  
During the trial, in which 7,466 women were enrolled, the subjects were given either the HPV vaccine Cervarix or a hepatitis A vaccine. While researchers intended to give the women receiving Cervarix the full three doses, 20 percent of them got only one or two doses for various reasons, USA Today reports.
Researchers found that after four years, two does of Cervarix offered the same protection level against HPV infection as three. Even one dose still offered a high level of protection.
"Our clinical efficacy data provide suggestive evidence that an HPV vaccine program that provides fewer doses to more women could potentially reduce cervical cancer incidence more than a standard three dose program that uses the same total number of doses but in fewer women," the researchers wrote, according to USA Today.
The researchers said that more studies are required to evaluate the long-term effectiveness of fewer doses.

Cervarix is one of two vaccines approved by the U.S. Food and Drug Administration to protect against the two types of HPV that are responsible for 70 percent of cervical cancer cases worldwide each year.
"The age-old adage of less is more may apply to HPV vaccination, and if so, the report…represents an important step on the road to more effective and sustainable cervical cancer prevention programs," Cosette Marie Wheeler of the University of New Mexico said in an editorial accompanying the journal article, USA Today reports.