What is Cervarix?
Cervarix is a vaccine consisting of a injectable suspension containing purified proteins for two types of the human papillomavirus (types 16 and 18). It is available in vials or in pre-filled syringes.
What is Cervarix used for?
Cervarix is indicated in women and girls as young as nine years old to protect against precancerous lesions (abnormal cell proliferation) in the cervix (cervix) and cervical cancer that are caused by infections with certain types of carcinogenic human papilloma virus (HPV).
Cervarix is given according to official recommendations.
The vaccine can only be obtained with a prescription.
How is Cervarix used?
Cervarix is given in three doses. An interval of one month is recommended between the first and second dose and an interval of five months between the second and third dose. However, if necessary, the second and third doses can be administered leaving a longer period. It is recommended that, once the first dose of Cervarix is received, the treatment should be completed by taking all three doses. The vaccine is given as an injection into the shoulder muscle.
How does Cervarix work?
Papillomaviruses are viruses that cause warts and abnormal tissue growth. There are over 100 types of papillomavirus, some of which are associated with genital tumors. HPV types 16 and 18 are responsible for around 70% of cervical carcinomas.
All papillomaviruses have an envelope or "capsid", made up of proteins called "L1 proteins". Cervarix contains purified L1 proteins for HPV types 16 and 18; these are produced with a method known as "recombinant DNA technology", ie they are obtained from a cell that has received a gene (DNA) which makes it capable of generating L1 proteins. Proteins are collected in "virus-like particles" (structures that resemble HPV viruses, so that the body has no difficulty in recognizing them).
When a patient receives the vaccine, the immune system produces antibodies against L1 proteins. Antibodies help destroy the virus. Following vaccination, the immune system is able to produce antibodies more quickly when exposed to real viruses. This will help protect against diseases caused by these viruses.
The vaccine is produced with an "adjuvant system" that contains MPL, a purified lipid (a fatty substance) extracted from bacteria, which enhances the immune system's response to the vaccine. The vaccine is "adsorbed", ie the virus-like particles and MPL are fixed on an aluminum compound to stimulate a better immune response.
What studies have been carried out on Cervarix?
The main study conducted on Cervarix involved almost 19, 000 women aged 15 to 25 years. Cervarix has been compared with another vaccine that is not active against HPV viruses (specifically, a vaccine against hepatitis A virus). The study examined how many women, who in the vast majority at the start of the study had no type 16 or 18 HPV infection, developed precancerous cervical lesions related to a type 16 or 18 HPV infection. Participants the study was kept under observation for up to four years after the first dose of vaccines was administered.
Two additional studies examined the development of antibodies against HPV type 16 and 18 in 2 225 girls aged 10 to 14 years. Two further studies examined the development of antibodies against HPV type 16 and 18 in 1, 792 girls aged 9 to 25 years. The studies compared antibody levels before vaccination and after the third dose.
What benefit has Cervarix shown during the studies?
Cervarix was more effective than the comparison vaccine in preventing abnormal cell proliferation in the cervix. In the main study, after 39 months on average, among over 7, 000 women vaccinated with Cervarix and who had never had an HPV infection of type 16 or 18, four developed precancerous lesions in the cervix related to an HPV infection of the indicated types, compared to 56 of the over 7 000 women who received the other vaccine. The study also showed that Cervarix can offer protection against infections or injuries related to other types of HPV.
Additional studies showed that all girls aged 9 and above, vaccinated with Cervarix, developed levels of protective antibodies against HPV type 16 and 18, indicating that the vaccine is probably effective in preventing HPV infections in girls from age. of 9 years.
What is the risk associated with Cervarix?
The most common side effects associated with Cervarix (seen in more than 1 patient in 10) are headache, myalgia (muscle pain), reactions at the injection site including pain, redness and swelling, fatigue (tiredness). For the full list of all side effects reported with Cervarix, see the Package Leaflet.
Cervarix should not be used in people who may be hypersensitive (allergic) to the active substance or to any of the other ingredients. Vaccination should be postponed in patients with high fever.
Why has Cervarix been approved?
The CHMP decided that Cervarix's benefits are greater than its risks and recommended that it be given marketing authorization.
More information on Cervarix:
On 20 September 2007, the European Commission granted GlaxoSmithKline Biologicals sa a marketing authorization valid for Cervarix throughout the European Union.
For more information on Cervarix therapy, read the package leaflet (also part of the EPAR) or contact your doctor or pharmacist.
Last update of this summary: 12-2011.
