The Future III base study was a 48-month randomized, placebo controlled, multinational study evaluating the prophylactic administration of GARDASIL™ in 24-45 year old women. The long-term follow-up (LTFU) study was conducted in Colombia to observationally describe the safety of quadrivalent HPV vaccine (qHPV vaccine), its immunogenicity and effectiveness in preventing HPV 6-,11-,16-,18-related cervical intraepithelial neoplasia (CIN) or condyloma for up to 10 years. We present the final study data.
The LTFU study enrolled 685 of 805 Colombian subjects who received qHPV vaccine during the base study (early vaccination group, EVG). Study visits were conducted at Year 6, 8 and 10 and included history taking, pelvic exams with Pap tests, and biopsy of cervical/external genital lesions if present. Endpoint adjudication was performed by an independent panel. Immunogenicity was measured for each vaccine HPV type. Primary analyses were performed per-protocol.
There was no case of HPV 6-,11-,16-,18-related CIN or condyloma in the EVG during the LTFU study. The cumulative incidence probabilities from Year 4 to Year 8 and Year 6 to Year 10 of the LTFU study were 0.0, respectively, compared to 0.0006 (95% confidence interval 0.0001; 0.0045) for the 4-year interval of the base study, indicating no waning of vaccine effectiveness. Vaccine induced HPV type-specific antibody responses were durable. No serious adverse events related to qHPV vaccine or study procedure were reported.
The prophylactic administration of qHPV vaccine to mid-adult women is effective and generally safe through 10 years post Dose 1 and induces durable immune responses.