Comparison of the immunogenicity and reactogenicity of Cervarix and Gardasil human papillomavirus vaccines in HIV-infected adults: a randomized, double-blind clinical trial

BACKGROUND

We compared the immunogenicity and reactogenicity of Cervarix or Gardasil human papillomavirus (HPV) vaccines in adults infected with the human immunodeficiency virus (HIV).

METHODS

This was a double-blind, controlled trial randomizing HIV-positive adults to receive 3 doses of Cervarix or Gardasil at 0, 1.5, and 6 months. Immunogenicity was evaluated for up to 12 months. Neutralizing anti-HPV-16/18 antibodies were measured by pseudovirion-based neutralization assay. Laboratory tests and diary cards were used for safety assessment. The HPV-DNA status of the participants was determined before and after immunization.

RESULTS

Ninety-two participants were included in the study. Anti-HPV-18 antibody titers were higher in the Cervarix group compared with the Gardasil group at 7 and 12 months. No significant differences in anti-HPV-16 antibody titers were found among vaccine groups. Among Cervarix vaccinees, women had higher anti-HPV-16/18 antibody titers compared to men. No sex-specific differences in antibody titers were found in the Gardasil group. Mild injection site reactions were more common in the Cervarix group than in the Gardasil group (91.1% vs 69.6%; P = .02). No serious adverse events occurred.

CONCLUSIONS

Both vaccines were immunogenic and well tolerated. Compared with Gardasil, Cervarix induced superior vaccine responses among HIV-infected women, whereas in HIV-infected men the difference in immunogenicity was less pronounced.

Uptake, coverage, and completion of quadrivalent human papillomavirus vaccine in the vaccine safety Datalink, July 2006-June 2011

PURPOSE

The Advisory Committee on Immunization Practices recommended quadrivalent human papillomavirus vaccine (HPV4) for use in females in June 2006 and in males in October 2009. The objective of our study was to describe HPV4 uptake, single-dose coverage, and completion of the three-dose series among those 9-26 years of age, after the respective female and male vaccine licensures through June 2011.

METHODS

The study population included members of eight managed care organizations participating in the Vaccine Safety Datalink; we abstracted demographic and comprehensive vaccine information from electronic health records.

RESULTS

We found one-dose coverage increasing throughout the study period, to a high of 37.7% among females and 1.3% among males in June 2011. Among those receiving at least one HPV4 dose, three-dose series completion was 42% for females and 30.2% for males.

CONCLUSIONS

Our results demonstrate low initiation and completion of the HPV4 series among those recommended to receive the vaccine. Although consistent with previous studies, these results highlight the continued need to develop, implement, and monitor strategies to increase HPV4 vaccine initiation and completion in younger adolescents to achieve maximum impact in reducing the burden of cervical cancer and other HPV-related diseases.

A novel vaccine for cervical cancer: quadrivalent human papillomavirus (types 6, 11, 16 and 18) recombinant vaccine (Gardasil)

Human papillomaviruses (HPVs) are one of the most common sexually transmitted infections and remains a public health problem worldwide. There is strong evidence that HPV causes cervical, vulva and vaginal cancers, genital warts and recurrent respiratory papillomatosis. The current treatments for HPV-induced infections are ineffective and recurrence is common-place. Therefore, to reduce the burden of HPV-induced infections, several studies have investigated the effi cacy of different prophylactic vaccines in clinical human trials directed against HPV types 6, 11, 16, or 18. Notably, these HPV types contribute to a signifi cant proportion of disease worldwide. This review will focus on the published results of Merck & Co’s prophylactic quadrivalent recombinant vaccine targeting HPV types 6, 11, 16, and 18 (referred to as Gardasil^®). Data from the Phase III trial demonstrated that Gardasil was 100% effi cacious in preventing precancerous lesions of the cervix, vulva, and vagina and effective against genital warts. Due to the success of these human clinical trials, the FDA approved the registration of Gardasil on the 8 June 2006. In addition, since Gardasil has been effi cacious for 5 years post vaccination, the longest evaluation of an HPV vaccine, it is expected to reduce the incidence of these type specifi c HPV-induced diseases in the future.

Review of Gardasil

Human papillomavirus (HPV) is necessary for the development of cervical cancer. Cervical cancer is the second most common cancer in women worldwide but 80% occurs in developing countries, not countries with Pap screening programs. Pap screening programs in industrialized countries have reduced the incidence of cervical cancer to 4-8/100,000 women. HPV vaccines may be a promising strategy for cervical cancer in women without access to screening programs. In industrialized countries, the benefit of HPV vaccines focuses on individual abnormal Pap test reduction not cancer prevention. The focus of this review is to cover the side effects of Gardasil in perspective with the limited population benefit cervical cancer reduction in countries with organized Pap screening programs. In addition, information about Gardasil benefits, risks and unknowns for individual patient decision making for vaccination is presented. Gardasil offers protection against CIN 2+ lesions caused by HPV 16/18 and against genital warts caused by HPV 6/11 for at least 5 years. Combining Gardasil with repeated cytology screenings may reduce the proportion of abnormal cytology screens and hence reduce the associated morbidity with the subsequent colposcopies and excisional procedures.