Long-term studies have demonstrated continued protection against vaccine-specific HPV types present in licensed VLP-based quadrivalent (6/11/16/18) and bivalent vaccine (16/18) for up to 9 years.1,2 However, a limited number of long-term studies and analyses of clinical studies have shown that cross-protection post-vaccination for non-vaccine types is partial at best, and markedly wanes over time.3-5 As such, the 9-valent vaccine may provide consistent and long-term protection against the 9 types in the vaccine. This analysis was undertaken to estimate the impact of VLP-based HPV vaccination on HPV infection as related to vaccine-specific types over time.
The effects of quadrivalent (types 6/11/16/18) and 9-valent (types 6/11/16/18/31/33/45/52/58) vaccines on HPV types 16/18/31/33/45/52/58-related incidences of cervical cancer, cervical intraepithelial neoplasia (CIN) 1 and CIN2/3 were compared. A model based on clinical trial data from the vaccines in >16,000 females of up to 6 year durations was used to estimate protection over time.
The incidences of cervical cancer, CIN1 and CIN2/3 were reduced for the HPV-related vaccine types 16 and 18 for the quadrivalent vaccine, and for types 16/18/31/33/45/52/58 for the 9-valent vaccine. The 9-valent vaccine reduced cases of cervical cancer by an additional 21%, CIN1 by an additional 38%, and CIN2/3 by an additional 33%, compared with the quadrivalent vaccine, as estimated through 100 years.
Vaccination with the VLP-based HPV quadrivalent and 9-valent vaccines is expected to provide consistent and long-term protection against infection and disease caused by HPV types represented in the VLP-based vaccine. This includes a high level of type-specific protection against the HPV types represented in the 9-valent HPV vaccine (6/11/16/18/31/33/45/52/58).
1. Kjaer SK, Nygard M, Dillner J et al. Long-Term Effectiveness and Safety af Gardasil™ in the Nordic Countries. European Research Organization on Genital Infection and Neoplasia February 4-7. OC 6-1 (2015). Available at http://www.eurogin.com/2015/images/pdf/eurogin-2015_abstracts_part_2.pdf (accessed 21 Dec 2015).
2. Naud PS, Roteli-Martins CM, De Carvalho NS et al. Sustained efficacy, immunogenicity, and safety of the HPV-16/18 AS04-adjuvanted vaccine: final analysis of a long-term follow-up study up to 9.4 years post-vaccination. Hum. Vaccin. Immunother. 2014; 10: 2147-62.
3. Malagon T, Drolet M, Boily MC,et al. Cross-protective efficacy of two human papillomavirus vaccines: a systematic review and meta-analysis. Lancet Infect. Dis. 2012; 12: 781-89.
4. Brown D, Kulkarni A, Matt Pillsbury et al. Clarification on the Impact of Cervarix Vaccination on Human Papillomavirus Infection and Cervical Cancer in the United Kingdom. Hum. Vaccin. Immunother, 2016; in press.
5. Kreimer AR, Struyf F, Rosario-Raymundo MR et al. Efficacy of fewer than three doses of an HPV-16/18 AS04-adjuvanted vaccine: combined analysis of data from the Costa Rica Vaccine and PATRICIA trials. Lancet Oncol. 2015; 16: 775-86.