Correlation between levels of human papillomavirus (HPV)-16 and 18 antibodies in serum and cervicovaginal secretions in girls and women vaccinated with the HPV-16/18 AS04-adjuvanted vaccine
ABSTRACT This pooled analysis of data from four Phase III clinical trials was undertaken to assess the correlation between levels of anti-human papillomavirus (HPV)-16/18 antibodies in serum and cervicovaginal secretions (CVS) in girls and women vaccinated with the HPV-16/18 AS04-adjuvanted vaccine. Serum and CVS samples were collected from a subset of women aged 10-65 years (N=350) at pre-specified time-points from 7 to 36 months post-vaccination. Anti-HPV-16/18 antibody levels in serum and CVS were measured by enzyme-linked immunosorbent assay. Pearson correlation coefficients between serum and CVS antibody levels, standardized for total immunoglobulin G, were calculated at each time-point in women with detectable antibodies in both serum and CVS. All subjects had seroconverted at Month 7 and remained seropositive through Month 36 for both antigens. Geometric mean titers of anti-HPV-16/18 antibodies in serum were substantially higher at all time-points than those in a control group of women who had cleared a natural HPV infection in another trial. In women with detectable antibodies in both serum and CVS, good correlation was seen between HPV-16/18 antibody levels at all time-points (Pearson correlation coefficient: 0.84-0.92 for HPV-16 and 0.90-0.91 for HPV-18). The strong correlation between levels of HPV-16/18 antibodies in serum and CVS up to 36 months post-vaccination in girls and women vaccinated with the HPV-16/18 AS04-adjuvanted vaccine supports transudation of serum antibodies as the mechanism by which antibodies are introduced into CVS. These CVS antibodies may play a role in the protective efficacy of this vaccine.
- [Show abstract] [Hide abstract]
ABSTRACT: HPV infection with ‘high-risk’ genotypes is associated with ano-genital and oropharyngeal cancers. Two currently licensed prophylactic HPV vaccines designed to prevent disease associated with HPV 16 and 18 are in use around the world. Both vaccines have very high efficacy for prevention of vaccine type–associated cervical precancers, preventing approximately 70% of these lesions. Quadrivalent HPV vaccine has also been shown to prevent HPV16/18-associated vaginal, vulvar and anal precancers, and HPV6/11-associated ano-genital warts. To broaden protection against HPV genotypes not in the current vaccines, ‘second-generation’ vaccines with additional genotypes are under development. Merck, Sharp and Dohme has submitted a Biologics License Application for its investigational nonavalent HPV vaccine V503 to the US FDA, with standard review being granted. The nonavalent HPV vaccine appears to be safe and effective in preventing persistent infection and precancerous lesions associated with HPV types 16/18/31/33/45/52/58, as well as genital warts related to HPV types 6 and 11.Expert Review of Vaccines 09/2014; 13(11). DOI:10.1586/14760584.2014.963561 · 4.22 Impact Factor
- [Show abstract] [Hide abstract]
ABSTRACT: Immunogenicity and safety of the human papillomavirus (HPV)-16/18 AS04-adjuvanted vaccine were evaluated in healthy Chinese females aged 9-45 years in 2 phase IIIB, randomized, controlled trials. Girls aged 9-17 years (ClinicalTrials.gov, NCT00996125) received vaccine (n = 374) or control (n = 376) and women aged 26-45 years (NCT01277042) received vaccine (n = 606) or control (n = 606) at months 0, 1, and 6. The primary objective was to show non-inferiority of anti-HPV-16 and -18 immune responses in initially seronegative subjects at month 7, compared with Chinese women aged 18-25 years enrolled in a separate phase II/III trial (NCT00779766). Secondary objectives were to describe the anti-HPV-16 and -18 immune response, reactogenicity and safety. At month 7, immune responses were non-inferior for girls (9-17 years) vs. young women (18-25 years): the upper limit of the 95% confidence interval (CI) for the geometric mean titer (GMT) ratio (women/girls) was below the limit of 2 for both anti-HPV-16 (0.37 [95% CI: 0.32, 0.43]) and anti-HPV-18 (0.42 [0.36, 0.49]). Immune responses at month 7 were also non-inferior for 26-45 year-old women vs. 18-25 year-old women: the upper limit of the 95% CI for the difference in seroconversion (18-25 minus 26-45) was below the limit of 5% for both anti-HPV-16 (0.00% [-1.53, 1.10]) and anti-HPV-18 (0.21% [-1.36, 1.68]). GMTs were 2- to 3-fold higher in girls (9-17 years) as compared with young women (18-25 years). The HPV-16/18 AS04-adjuvanted vaccine had an acceptable safety profile when administered to healthy Chinese females aged 9-45 years.Human Vaccines & Immunotherapeutics 04/2014; 10(7). DOI:10.4161/hv.28702 · 3.64 Impact Factor
Article: HPV Vaccination and Cervical Cancer[Show abstract] [Hide abstract]
ABSTRACT: Cervical cancer is the third most common cancer in women worldwide and often affects women under 40 years with young families. Vaccination against the human papillomavirus (HPV) is a major advance, since it offers primary prevention against the infectious agent that is the main cause of the disease. Two prophylactic vaccines have shown great promise in clinical trials. One of these (Gardasil®) contains all four HPV types, offering protection against genital warts (types 6 and 11) as well as cervical cancer (types 16 and 18). The other (Cervarix®) contains types 16 and 18, targeting cervical cancer alone, but also has a degree of cross-protection against types 31 and 45, which could significantly increase the level of protection. Adolescent girls remain the primary target of vaccination programmes, but the issues of vaccinating boys and older women are increasingly debated.Current Oncology Reports 08/2012; 14(6). DOI:10.1007/s11912-012-0259-3 · 2.87 Impact Factor