Cervarix

Cervarix is a vaccine against certain types of the human papillomavirus (HPV).

Cervarix is designed to prevent infection from HPV types 16 and 18, which currently cause about 70% of cervical cancer cases. Type 16 is also associated with oropharyngeal squamous-cell carcinoma, a form of throat cancer. Additionally, some cross-reactive protection against virus strains 45 and 31 were shown in clinical trials. Cervarix is also formulated with AS04, a proprietary adjuvant that has been found to boost the immune system response for a longer period of time.

Indications

Cervarix is a preventative cervical cancer vaccine, not therapeutic. HPV immunity is type-specific, so a successful series of Cervarix shots will not block infection from cervical cancer-causing HPV strains other than HPV 16, 18, 31 and 45, so experts continue to recommend routine cervical Pap smears even for women who have been vaccinated.

Biotechnology

Cervarix is created using the L1 protein of the viral capsid. Recombinant activity in a baculovirus vector produces L1 protein spheres, which are very immunogenic. The viral proteins induce the formation of neutralizing antibodies. The vaccine contains no live virus and no DNA, so it cannot infect the patient. The vaccine was developed, in parallel, by researchers at Georgetown University Medical Center, the University of Rochester, the University of Queensland in Australia, and the U.S. National Cancer Institute.

Clinical trials

Phase II trials demonstrated 100% protection of the vaccine against types 16 and 18 HPV, including among 1100 women from North America and Brazil. Phase III trials included over 660 women from Germany and Poland. Company officials are now conducting a clinical trial to determine whether Cervarix is more effective than rival Merck's HPV vaccine Gardasil.

Longevity of the vaccination has proven so far to be at least 5.5 years. In the clinical trials, women were given three doses over a six-month span -- at 0 month, 1 month, and 6 months. The technology used in this vaccine was licensed from the University of Rochester.

Regulatory Approval

• Australia - It received approval in May 2007 in Australia for women ages 10 to 45.
• Philippines - On August 25, 2007 GlaxoSmithKline launched Cervarix in the Philippines after approval by the local Bureau of Food and Drugs.
• European Union - It was approved in September 2007 in the European Union.
• United States of America On March 29, 2007 GlaxoSmithKline submitted a Biologics License Application (BLA) for Cervarix (human papillomavirus vaccine, AS04 adjuvant-adsorbed), to the FDA which included data from clinical trials in almost 30,000 females 10 to 55 years of age and contains data from the largest Phase III cervical cancer vaccine efficacy trial to date.
• GSK awaiting results of further trials to submit to the FDA. Approval is not expected before late 2009.

Use

Cervarix is used by the UK government for its national programme of vaccination for teenage girls. This caused some controversy since Cervarix was chosen over Gardasil apparently for cost reasons, even though Gardasil protects against HPV strains 6 and 11 in addition to 16 and 18.