Vaccine initiation and 3-dose series completion of 4vHPV vaccine among US insured males 2012-2016.

OBJECTIVE The quadrivalent human papillomavirus vaccine (4vHPV, GARDASIL®), was approved in the US in 2009 for use in males aged 9 to 26 for the prevention of HPV-related genital warts, and in 2010 for the prevention of certain HPV-related anogenital diseases. A regimen was approved in 2016 for those who initiate the vaccine series between the ages of 9 to 14 years. We describe patterns of 4vHPV administration among US males before this modification. METHODS The study used a US health insurance claims database, and included males, age 9 to 26 years, who initiated 4vHPV between 2012 and 2016. Time from first dose to subsequent doses was estimated. Logistic regression identified factors associated with regimen completion. RESULTS Among 100,786 males who initiated 4vHPV (corresponding to ∼ 13% of male birth cohorts), 50,573 (50.2%) and 25,763 (25.6%) received a second and third dose, respectively. Annual administration was common, with 47% of males receiving 3 doses over 3 years (1 dose per year) as compared to 12% receiving the 3-dose series in the recommended 6-month timeframe. Receipt of 4vHPV was 2.2 (range 1.5 to 2.9) times as likely to occur in summer months compared to other times of the year. Individuals aged 18 to 21 years and those living in Western states or rural regions were less likely to complete the 3-dose regimen. CONCLUSIONS The real-world patterns of 4vHPV vaccination observed, particularly the low uptake and regimen completion, suggest that better strategies are needed for males to improve 4vHPV vaccine use in males.