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Comparing One or Two Doses of the Human Papillomavirus Vaccine for the Prevention of Human Papillomavirus Infection, ESCUDDO Study

Trial Status: closed to accrual and intervention

This phase IV trial investigates whether one dose of a human papillomavirus vaccine works as well as two doses in preventing human papillomavirus (HPV) infection. Certain types of HPV cause almost all cases of cervical cancer. Vaccines that protect against infection with these types of human papillomavirus may reduce the risk of cervical cancer. Both Gardasil-9 and Cervarix protect against HPV 16 and 18, which cause 70% of all cervical cancers. However, HPV vaccination rates are too low, especially in countries with very high rates of cervical cancer. HPV vaccines are expensive-many countries cannot afford them-more than one dose is needed, and giving multiple doses is difficult. Researchers want to find out if one dose prevents HPV infection. If it does, more people might get the vaccine.