A new study shows that women who received just one dose of the HPV vaccine, instead of the recommended three doses, had antibodies against the viruses that remained stable in their blood for four years. This suggests that the single dose may be enough to generate long-term immune responses that will protect against cervical cancer.
The research was published in Cancer Prevention Research, a journal of the American Association for Cancer Research, and announced in a press release.
Data from the Centers for Disease Control and Prevention on vaccination coverage showed that last year only 33 percent of girls received all three doses of the human papillomavirus vaccine.
In the study, antibody levels among women who received one dose were lower than those who received the full three doses, however the levels appeared stable. Researchers conclude that this suggests these are lasting responses.
"Our findings suggest promise for simplified vaccine administration schedules that might be cheaper, simpler, and more likely to be implemented around the world," said Mahboobeh Safaeian, Ph.D., an investigator in the Division of Cancer Epidemiology and Genetics at the National Cancer Institute in Betheseda, MD. "Vaccination with two doses, or even one dose, could simplify the logistics and reduce the cost of vaccination, which could be especially important in the developing world, where more than 85 percent of cervical cancers occur, and where cervical cancer is one of the most common causes of cancer-related deaths."
The researchers noted that they gathered information from Costa Rican women who used the Cervarix brand vaccine, and not the more widely used Gardasil. Safaeian says while their findings are promising, more research needs to be done before HPV vaccine guidelines or policies are changed.