Cervical cancer is the second leading cause of female cancer mortality worldwide, with 288,000 deaths annually. About 510,000 cases are reported each year, 80% of them in developing countries.
Two new vaccines are undergoing trial to prevent HPV infections, which causes cervical cancer. These vaccines must be given to girls before they are sexually active. The new vaccines are manufactured by GlaxoSmithkline against HPV 16 and 18 strains and the Merck Vaccine against HPV 16,18,6 and 11. These vaccines carry the L capsid protein and when given in 3 doses generate high levels of neutralizing antibodies.
Both the drugs are safe and show an efficacy of more than 90% in Phase I and II trials. These both vaccines are in their phase III trial and are expected to be in market in an other 2 years.
Studies are currently undergoing to find the duration and efficacy of the vaccine, its effect on menstrual cycle and the need for booster vaccine. Problems with the new vaccine are due to high cost, the dosages required are three injections and creating a cold chain for transport to rural areas. This vaccine should be modified to give protection against more HPV types and must be cheaper and easier to administer.
Experts say though this vaccine may be effective for prevention of infection a better promising approach for developing countries would be to undergo a cheaper screening test and visual inspection followed by prevention and treatment.