Long‐term persistence of systemic and mucosal immune response to HPV‐16/18 AS04‐adjuvanted vaccine in preteen/adolescent girls and young women

Abstract

Vaccination against oncogenic human papillomavirus (HPV) types is one key intervention for cervical cancer prevention. This follow‐up study assessed the persistence of the systemic and mucosal immune responses together with the safety profile of the HPV‐16/18 AS04‐adjuvanted vaccine administered to young women aged 10–25 years. Serum and cervicovaginal secretion (CVS) samples were collected at prespecified time‐points during the 48‐month follow‐up period. Anti‐HPV‐16/18 antibody levels in serum and CVS were measured by enzyme‐linked immunosorbent assay (ELISA). At Month 48, all subjects remained seropositive for serum anti‐HPV‐16 and ‐18 antibodies. As previously observed, anti‐HPV‐16 and ‐18 antibodies levels (ELISA Units/mL) were higher in subjects vaccinated at the age of 10–14 years (2862.2 and 940.8) compared to subjects vaccinated at the age of 15–25 years (1186.2 and 469.8). Moreover, anti‐HPV‐16 and ‐18 antibodies in CVS were still detectable for subjects aged 15–25 years (84.1% and 69.7%, respectively). There was a strong correlation between serum and CVS anti‐HPV‐16 and ‐18 antibodies levels (correlation coefficients = 0.84 and 0.90 at Month 48, respectively) supporting the hypothesis of transudation or exudation of serum immunoglobulin G antibodies through the cervical epithelium. The HPV‐16/18 AS04‐adjuvanted vaccine had a clinically acceptable safety profile. In conclusion, this follow‐up study shows that the HPV‐16/18 AS04‐adjuvanted vaccine administered to preteen/adolescents girls and young women induces long‐term systemic and mucosal immune response and has a clinically acceptable safety profile up to 4 years after the first vaccine dose.