By Jacob Puliyel
The writer, a doctor, is the Head of Pediatrics, St Stephen’s Hospital, Delhi, and a member of the National Technical Advisory Group on Immunisation. The views expressed are personal.
Dubious Vaccine for Cervical Cancer
Before a new vaccine is introduced it is first studied in a randomised controlled trial where some are given the drug and others are given an inert substance to check the effects and adverse effects among those given the new drug. Last week, Slate published a cover story on the investigation of the randomised trials of human papillomavirus (HPV ) vaccines before approval. The science editor conducted an eight-month long investigation, interviewed study participants and studied 2,300 pages of documents obtained through freedom-of-information requests from hospitals and health authorities.
Slate found that during the year-long study data on potential side effects were collected for only two weeks. The rest of the time individual trial investigators used their personal judgment to decide whether or not to report medical problems as adverse events. An oxymoronic instruction to investigators was to list new problems as ‘new medical history’. There is no evidence the confidential study protocol was submitted to regulators for approval. The worksheet investigators used allotted just one line per entry for new medical history, with no measurement of symptom severity, duration, outcome, or overall seriousness. Trial participants complained to Slate that repeated complaints of debilitating symptoms were not even registered in the study as potential side effects. The European Medicines Agency (EMA) is the regulator in Europe. In an internal 2014 EMA report about Gardasil 9 – a leading HPV vaccination – obtained through a freedom-of-information request, senior experts called the company’s approach “unconventional and suboptimal” and said it left some “uncertainty” about the safety results. In the EMA’s public assessment Gardasil 9, all mention of the safety concerns had been scrubbed.
Chronic Fatigue Syndrome
Not all recipients of the vaccine developed serious adverse effects. But there are numerous reports of chronic fatigue syndrome (CFS ) otherwise known as myalgic encephalomyelitis which is characterized by long-term fatigue that limits a person’s ability to carry out ordinary daily activities. Dr Jose Montoya, a professor of medicine at Stanford University explains that the condition usually starts with an insult to the immune system—a severe infection, a car crash, a pregnancy. The first symptoms are flu-like, but months go by and the patient realizes she isn’t getting better.’ In a few genetically predisposed individuals, Montoya told the Slate editor, it is “biologically plausible” that the vaccine, which mimics a natural infection, could also trigger an immune response powerful enough to lead to CFS. To find out if that is the case, trial investigators would need to carefully track participants’ symptoms “for at least one year.” CFS is not the only serious adverse effect reported. The American College of Pediatrics has suggested one of the HPV vaccines could possibly be associated with the very rare but serious condition of premature ovarian failure (POF), also known as premature menopause. In Japan, use of the vaccine in adolescents has been associated with such serious adverse events that it has been withdrawn from the immunisation programme.
Usefulness of Vaccine
HPV spreads only through sexual contact and therefore is not communicable in a casual manner. There are about 100 strains of HPV, and the vaccine only protects against 2, 4, or 9 of them, depending on the brand and 95% of HPV infections heal by themselves – potentially granting the individual lifetime immunity against the particular strain. Perhaps to improve uptake of the vaccine the manufacturers promote it as an anticancer vaccine rather than a vaccine against sexually transmitted disease. But while there is evidence that the vaccine reduces infection with the vaccine strains of the virus, non-vaccine strains have been known to replace the vaccine strain and these could produce cancer. There is currently no scientific study that shows the vaccine reduces cervical cancer in the women who are vaccinated. The efficacy of the vaccine against cancer is unknown
Cost-effectiveness READ MORE HERE.
Also published, 12/25 in the Tribune India was the following:
Prevention is Better Than Cure.
CN Purandare, Alka Kriplani & Neerja Bhatla IN India, cervical cancer is the second most common cancer in women, accounting for nearly one-fourth of the global burden of cervical cancer, with an estimated 122,800 new cases and 67,500 deaths annually, which is more than the number of deaths due to maternal mortality. Since these women are usually in their 40s and 50s, it is estimated that the years of life lost are greater in cervical cancer. Globally, cervical cancer accounts for 528,000 cases including 445,000 cases in low and middle income countries (LMICs).
The age-standardised incidence rate of cervical cancer varies between 5.6 and 24.3 per 100,000 women in different regions of India. Although a gradually declining trend in the cervical cancer incidence has been observed in different regions of India over the last two decades, the rates still remain significantly higher than in other Asian countries. In fact, the absolute numbers of both cervical cancer cases and deaths are on the increase due to population growth. In the West, repeated testing by Pap smear and consequent treatment of precancerous lesions led to a substantial decline in the numbers of cervical cancer cases. In India, with very limited resources to introduce and sustain effective population-based cervical cancer screening programs, there was not much progress in preventing this very preventable cancer. The discovery by Nobel laureate Harald zur Hausen that persistent infection with one of the oncogenic, high-risk types of human papillomaviruses (HPV) is the ‘necessary’ cause of cervical cancer; enabled the development of primary prevention using HPV vaccination. Presently available vaccines target the two types that are responsible for 70 per cent of cervical cancers worldwide. HPV 16 and HPV 18 and can prevent over 90 per cent of high-grade precancerous lesions caused by these types. In India, there is a greater proportion of these types, making it likely that the impact of vaccination will be better than has been observed already in research studies and in countries that have implemented the vaccine program.
Efficacy of doses
Fewer than three doses of HPV vaccine would substantially reduce costs, improve compliance, ease logistics and facilitate scale up in national immunization programs. Data to support this has emerged from trials. WHO, after reviewing the available evidence on less than 3-doses, has recommended a two-dose schedule for girls (at an interval of 6 months, which may be extended to 12 months to facilitate vaccination) if vaccination is initiated prior to 15 years of age and a three-dose schedule (at 0, 1-2, and 6 months) if vaccination is initiated after the 15th birthday and for immunocompromised individuals, including those infected with HIV.
Countries implementing Immunisation
More than 80 countries have introduced HPV vaccine in the national immunisation programs (NIPs), of which 33 are LMICs; in addition, 25 LMICs have introduced HPV vaccination in pilot demonstration programs as a prelude to national scaling up in NIPs. In most programs a school-based approach is predominantly used to deliver the vaccine to the targeted adolescents with additional efforts using field clinics, and primary health centres to cover girls who missed vaccination and do not attend schools. Gavi The Vaccine Alliance has been able to markedly reduce the procurement price of both vaccines to Rs $5. While Australia, Denmark, USA and Canada were the first high-income countries to introduce HPV vaccination in NIPs in 2007, Panama (2008) in Latin America, Bhutan (2009) in Asia and Rwanda (2010) in Africa were the first LMICs that introduced HPV vaccination. Early reports of protection offered by the vaccine at the population level against vaccine targeted HPV infections, genital warts and cervical premalignant lesions have already started coming from countries that introduced the vaccine between 2007 and 2010.
HPV vaccine safety
Extensive data on the safety of HPV vaccines are now available from clinical trials and the population programs. Globally more than 270 million doses have been administered with no serious adverse events linked to the HPV vaccine and with an excellent safety profile. A meta-analysis of vaccine trials concluded that the frequency of serious adverse events (OR 0.99; 95%CI 0.87-1.14) and death (OR 0.91, 95%CI 0.39-2.14) were similar in the vaccinated and control groups. The majority of deaths reported were accidental in nature, and none was attributable to the vaccines. Various rare syndromes have also been studied and none found to be related to the vaccine. A recently published study from India reported no serious adverse event attributable to the vaccine after administering 34,856 doses of the quadrivalent vaccine to 10-18 year old girls and following them over four year.