02 Oct FDA Approved HPV Vaccine
FDA Approved HPV Vaccine.
Background: Cancers figure among the leading causes of morbidity and mortality worldwide, with approximately 14 million new cases and 8.2 million cancer related deaths in 2012(World Cancer Report 2014). The number of new cases is expected to rise by about 70% over the next 2 decades. Among men, the 5 most common sites of cancer diagnosed in 2012 were lung, prostate, colorectum, stomach, and liver cancer. Among women the 5 most common sites diagnosed were breast, cervix (cervical cancer),colorectum, lung, and stomach cancer.
Cervical cancer is one of the world’s deadliest – but most easily preventable – forms of cancer for women,responsible for more than 270 000 deaths annually, 85% of which occur in developing countries. Cervical cancer is caused by persistent infection of high risk HPV (Human Papillomavirus) infection.
HPV are a group of more than 200 related viruses. More than 40 HPV types can be easily spread through direct sexual contact, from the skin and mucous membranes of infected people to the skin and mucous membranes of their partners. They can be spread by vaginal, anal, and oral sex. Other HPV types are responsible for non-genital warts, which are not sexually transmitted. So, HPV Vaccine was introduced to prevent cervical cancer known to be caused by persistent infection with one or more of the high risk genotypes of the Human Papillomavirus.
FDA approved available vaccines, dose schedule and recommended age for vaccination are as follows:
– Girls receiving a first dose of HPV vaccine before the age of 15 years can use a two dose schedule. The interval between the two doses should be six months.
– WHO recommends the HPV vaccine for girls in the age group of 9–13 years.
– Because the vaccines do not protect against all HPV types that can cause cervical cancer, girls vaccinated against HPV will still require cervical cancer screening later in their lives.
– Vaccinating girls before initiation of sexual activity is an important primary prevention intervention in a comprehensive cervical cancer prevention and control programme.
– Two vaccines that prevent infections from high-risk HPV types 16 and 18 are presently licensed in most countries; they both have excellent safety records.
– Currently, three HPV vaccines providing protection against high-risk HPV types have been licensed by FDA, and all of them are available in most countries.
– The bivalent vaccine Cervarix (protection against types 16 and 18 only) which are responsible for approximately 70% of cervical cancer cases in all countries around the world.
– The quadrivalent vaccine Gardasil (contains additional protection against types 6 and 11, which are responsible for 90% of benign anogenital warts or condyloma).
– The nonavalent vaccine Gardasil protecting against HPV types 16/18/6/11/31/33/45/52/58 and can provide a protection against almost 90%.
– Girls or women receiving a first dose of HPV vaccine after the age of 15 years can use a three dose schedule which are 0, 1, 6 months.
The quadrivalent vaccine protecting against human papilloma virus (HPV) types 16/18/6/11 was licensed in 2006, and the bivalent vaccine protecting against infection with HPV-16/18 was licensed in 2007. Both vaccines protect against the oncogenic varieties of HPV-16/18 that cause 70% of all cervical cancers and precancers, as well as many cancers of the vulva, vagina, anus, and throat (Human papillomavirus vaccines: WHO position paper. 2014 Oct;89,43:465–91). The nonavalent HPV vaccine protecting against HPV types 16/18/6/11/31/33/45/52/58 was approved by the USA Food and Drug Administration in December 2014 and can provide a protection against almost 90%.
Key messages about HPV Vaccination:
– There is a safe, effective vaccine that can protect against cervical cancer.
– The HPV vaccine works best if received before sexual activity begins.
– All girls in the age cohort or in the school class/grade/year identified as the target population by the national programme should receive the HPV vaccine.
– HPV vaccines do not treat or get rid of existing HPV infections.
– Girls who are already sexually active can also be given the HPV vaccine, though it may be less effective.
– Cervical cancer can be prevented by regular screening and HPV vaccination.
Because the vaccines do not protect against all HPV types that can cause cervical cancer, girls vaccinated against HPV will still require cervical cancer screening later in their lives.
Dr. Saima , Ph.D ( Molecular Biology), All India Institute of Medical Sciences, New Delhi, India.
(http://www.bio-services.org/hpv-vaccine-hype-or-hope/)
October 2, 2016
References:
Asian Pac J Cancer Prev. 2016;17(8):3663-73.
HPV and Cervical Cancer Epidemiology – Current Status of HPV Vaccination in India.
https://www.ncbi.nlm.nih.gov/pubmed/27644600