Antibody responses among adolescent females receiving two or three quadrivalent human papillomavirus vaccine doses at standard and prolonged intervals.
DOI: 10.1016/j.vaccine.2017.12.042; PMCID: PMC6055998
BACKGROUND: The originally recommended dosing schedule, 0, 2, 6 months, for the 3-dose quadrivalent human papillomavirus vaccine (4vHPV) was often not followed, resulting in longer than recommended intervals between doses and interest in the effect of prolonged intervals. Recent two-dose recommendations require investigations into the effect of delaying dose 2.
METHODS: This multi-site, prospective study enrolled healthy 9-17 year old girls (n = 1321) on the day of or within 28 days following a third dose of 4vHPV vaccination. Antibody titers to 4vHPV types were measured at one and six months post-dose 3 from all participants and post-dose 2 from participants who were on time for dose 3. To compare antibody responses, participants were categorized into groups: second and third doses on time (control group); on-time dose 2, substantially late dose 3 (group 2); substantially late dose 2, on-time dose 3 (group 3); both doses substantially late (group 4). Analyses compared age-adjusted geometric mean titers (GMTs) at one-month and six-months post-dose 3, effect of delaying the second dose, and two versus three doses as well as post-dose 2 GMTs, stratified by age.
RESULTS: Compared to on-time dosing, one-month post-dose 3 GMTs were non-inferior in groups 2, 3, and 4 and were superior in group 2. Six month post-dose 3 GMTs were superior in groups 2, 3, and 4 for each genotype, except HPV 18 in group 3. Age-adjusted post does 2 titers were significantly lower than post-dose 3 titers when dose 2 was on time but were significantly higher when dose 2 was substantially late. Participants ≥15 years old had no difference in post-dose 2 titers compared todelayed.
CONCLUSIONS: Prolonged intervals between doses do not appear to diminish and may enhance antibody response to 4vHPV. ClinicalTrials.gov (NCT00524745).
Adolescent; Alphapapillomavirus; Antibodies, Viral; Antibody Formation; Child; Female; Humans; Immunization Schedule; Immunization, Secondary; Papillomavirus Infections; Papillomavirus Vaccines; Prospective Studies; Sex Factors; Time Factors; Vaccination
Dosing; Geometric mean titers; Human papillomavirus; Immunity; Interval; Vaccine
Widdice LE, Unger ER, Panicker G, et al. Antibody responses among adolescent females receiving two or three quadrivalent human papillomavirus vaccine doses at standard and prolonged intervals. Vaccine. 2018;36(6):881-889. doi:10.1016/j.vaccine.2017.12.042