Effectiveness of 'catch-up' human papillomavirus vaccination to prevent cervical neoplasia in immunosuppressed and non-immunosuppressed women.

It is unknown whether the HPV vaccine is effective in immunocompromised women during catch-up ages. We performed a case-control study of 4,357 women with incident CIN2+ (cases) and 5:1 age-matched, incidence-density selected controls (N = 21,773) enrolled in an integrated health care system from 2006 to 2014. Vaccine effectiveness was estimated from multivariable conditional logistic regression models, with results stratified by immunosuppression history, defined as prior HIV infection, solid organ transplant history, or recently prescribed immunosuppressive medications. HPV vaccination resulted in a 19% reduction in CIN2+ rates for women without an immunosuppression history but a nonsignificant 4% reduction for women with an immunosuppression history. Further research is needed to evaluate whether catch-up HPV vaccine effectiveness varies by immunosuppression status, especially given the recent approval of the HPV vaccine for adults up to 45 years of age.