Cervical cancer vaccines, still shots in the dark
The HPV vaccine, administered to pre-pubescent girls to prevent cervical cancer, has received considerable bad press over its 14 years. Amrita Singh examines why the controversy refuses to die down
The HPV (human papillomavirus) vaccine has been the subject of a decade-long debate both in India and in other parts of the world. Questions about its efficacy, safety and affordability have dominated the debate since it was introduced in 2006 in the USA by pharmaceutical giants Glaxosmithkiine and Merck & Co. The two companies’ respective vaccines — the former’s Cervarix and the latter’s Gardasil — were widely marketed as the best available prophylactic, or preventive, for cervical cancer. Cervical cancer is a cancer that originates in the cervix, which connects the uterus to the vagina. According to the World Cancer
Report released this month, cervical cancer cases in India account for one-fifth of the world’s cancer cases, making it the second largest cancer threat to women after breast cancer.
Since an estimated 80 per cent of the world’s cervical cancer cases take place in developing countries such as India, in 2008 the government of the time approved the sale of both vaccines. Many gynaecologists and paediatricians welcomed the vaccine as being revolutionary and advocated its use despite its high cost (it was priced at about ~10,000 about a decade ago). But some in the medical community felt that the vaccine promised more than it could deliver. “There are about 40 known strains of the virus, so does the vaccine protect against all these strains?” asked a Gurugram doctor back in 2008 when one woman was trying to understand whether her daughters should receive these vaccines.
A small minority of doctors did not administer the vaccine for a variety of similar reasons. They cited a lack of adequate long-term testing of the vaccine, unproven efficacy and disturbing news of adverse side effects such as neurological disorders.
Still, the overwhelming majority of gynaecologists and paediatricians encouraged parents to administer this vaccine to their prepubescent daughters. “I listened to my family paediatrician who said that I must get my daughter vaccinated. He has taken care of her since she was a baby and I trust him blindly,” says Surbhi Arora, a resident of Delhi, whose daughter is among the first lot of prepubescent girls to get the shot more than a decade ago.
Gardasil was the preferred choice, because it promises immunity against four of HPV’S cancer-causing strains (types 16, 18, 6 and 11) whereas Cervarix guards against only types 16 and 18. The HPV vaccines were expensive then and are expensive now, with doctors recommending three doses of the vaccine, each costing between ~2,000 and ~3,000. “It seems like a small cost to bear if it can protect against something like cervical cancer,” adds Arora.
The HPV vaccine has been considered most effective when administered to girls between the ages of 12 and 15 — that is, before the likely age of sexual activity. And reputable doctors continue to advocate its use, despite the faint air of controversy that still surrounds it.
The actual controversy occurred in 2008. An American NGO called Program for Appropriate Technology in Health (PATH) conducted what it called a cervical cancer “vaccination drive” in two states, Andhra Pradesh and Gujarat, in partnership with the Indian Council for Medical Research in 2009. The drive was called off in 2010 due to alleged ethical violations such as not taking the informed consent of parents, inadequate dissemination of information on possible side effects, etc. (Activists called PATH’S programme a “trial” of the vaccine, one that was conducted on unsuspecting rural and tribal girls to bolster their data.) By the time the drive (or trial) was halted, 24,000 girls had been vaccinated, out of which eight had died. A government investigation in 2015 did not establish any link between the deaths and the vaccine. The vaccine, Gardasil, continued to be commercially available.
Sarojini Nadimpally, a public health researcher, bioethicist and founder of the nonprofit SAMA Resource Group for Women and
Health, was one of the petitioners in the public interest litigation filed in the Supreme Court in 2012 for the alleged ethical violations. She says that priorities need to be righted. For her, educating women about the need for regular Pap smears (a common test to detect cervical cancer) and HPV screening (a more specific test) is far more important than pushing vaccines that have yet to fully establish their worth. “The HPV vaccine can only be a part of the strategy to bring down cervical cancer incidence and deaths. Public health funds should be diverted to relevant screening programmes and early diagnosis as well to combat this problem,” she says.
In 2017, the National Technical Advisory Group for Immunisation, the body tasked with introducing new vaccines and strengthening the Universal Immunisation Programme (UIP) in India, advised the government to make the HPV vaccine mandatory for girls between the ages of nine and 26. But the Swadeshi Jagaran Manch, an affiliate of the Hindu nationalist Rashtriya Swayamsevak Sangh (RSS), objected, writing to the prime minister: “It is our concern that this programme will divert scarce resources from more worthwhile health initiatives, diverting it to this vaccine of doubtful utility and that its adverse effects will erode confidence in the national immunisation programme and thereby expose children unnecessarily to the risk of more serious vaccinepreventable disease.” HPV vaccines are still not part of the UIP (though the states of Delhi and Punjab have included the vaccine in their respective state administration programmes).
A 2019 study by experts at Delhi’s All India Institute of Medical Sciences and Pune’s Centre for Disease Control and Prevention now suggests that one dose (rather than three) of the HPV vaccine may be sufficient to protect against cervical cancer. An indigenous vaccine is reportedly being developed by the Serum Institute of India, which will only have to be administered once and will therefore be more affordable. And since it will be produced domestically, the cost will reduce even further.
Meanwhile, a new version (Gardasil 9) is also now available. This can be administered to both males and females between the ages of 9 and 45 for the prevention of cervical, vulvar, vaginal, and anal cancers caused by HPV types 16, 18, 31, 33, 45, 52, and 58.
But the question mark continues to hang around the cervical cancer vaccines, the debate not quite settled. “About eight months ago, WHO changed its guidelines for the HPV vaccine. Instead of waiting for 30 years to see how a group of women who have been given the vaccine respond to it, we can administer the new vaccine to see if it is able to produce enough antibodies and sustain the count for a minimum of five years. If this happens without the need for a booster dose within this period, the vaccine will be considered successful,” says Somashekhar S P, head of department and chairman of surgical oncology at the Manipal Comprehensive Cancer Centre, Bengaluru.
His explanation implies that all those who received the HPV vaccine over the last 14 years of the vaccines’ commercial availability were effectively live trials. And, since cervical cancer can take 10 to 20 years to develop, the efficacy of the vaccines will be determined only when a majority of the girls and young women who got the shots in the first decade of the 2000s are seen to have remained cancer-free for 30 years.
Many are not waiting to see these results. Says Somashekhar, “I have given the shots to both my daughters because if there is a chance to protect them against cervical cancer right now, we must take it.”
‘PUBLIC HEALTH FUNDS SHOULD BE DIVERTED TO RELEVANT SCREENING PROGRAMMES AND EARLY DIAGNOSIS AS WELL TO COMBAT THIS PROBLEM’
SAROJINI NADIMPALLY Public health researcher and founder of SAMA Resource Group for Women