In what could be a significant opportunity to gradually eliminate cervical cancer at the population level, the Government of India recently announced the scientific completion of CERVAVAC, the quadrivalent Human Papilloma Virus (qHPV) vaccine, for the prevention of cancer. Despite being largely preventable, cervical cancer is the second most prevalent cancer in India after breast cancer. Deaths caused by cervical cancer in India account for nearly one-fourth of the world’s cervical cancer deaths. Even as cervical cancer occurs most often in women over age 30, according to the United States Centers for Disease Control and Prevention, all women are at risk.
According to the WHO, cervical cancer is the fourth most common cancer among women globally, with an estimated 604,000 new cases and 342,000 deaths in 2020. About 90 percent of the new cases and deaths worldwide in 2020 occurred in low and middle-income countries. Current estimates indicate that every year approximately 125,000 women are diagnosed with cervical cancer in India, of which over 75,000 die from the disease. 83 percent of invasive cervical cancers are attributed to HPVs 16 or 18 in India, and in 70 percent of cases worldwide. Cervical cancer kills one woman every eight minutes in the country.
A large majority of cervical cancer is due to the human papillomavirus (HPV). Two human papillomavirus (HPV) types (16 and 18) are responsible for nearly 50 percent of high grade cervical pre-cancers. Vaccination against HPV and screening and treatment of pre-cancer lesions are cost-effective ways to prevent cervical cancer as it can be cured if diagnosed at an early stage and treated promptly. In low-and middle-income countries, there is limited access to these preventative measures and cervical cancer is often not identified until it has further advanced and symptoms develop. In addition, access to treatment of cancerous lesions (for example, cancer surgery, radiotherapy and chemotherapy) is usually limited, resulting in a higher rate of death from cervical cancer in these countries.
Until now, the HPV vaccines available in India are produced by foreign manufacturers at an approximate cost of Rs 2,800 to Rs 3,500 per dose. Cervavac is likely to be significantly cheaper, slated to cost approximately Rs 200 to 400. Globally, there are four vaccines that have been prequalified by WHO, all protecting against HPV types 16 and 18.
The indigenous Cervavac was developed by the Pune-based Serum Institute of India in coordination with the Government of India’s Department of Biotechnology (DBT). After examining the clinical trial data of the vaccine, the government advisory panel National Technical Advisory Group on Immunisation (NTAGI) approved the vaccine. Cervavac received market authorisation approval from the Drug Controller General of India on July 12 this year. SII plans to launch the vaccine by the end of the year.
What is cervical cancer?
Cancer is a disease in which cells in the body grow out of control. Cancer is always named for the part of the body where it starts, even if it spreads to other body parts later. When cancer starts in the cervix, it is called cervical cancer.
Most cervical cancer cases are linked to certain strains of human papillomavirus (HPV), a common virus that is transmitted through sexual contact. Long-lasting infection with certain types of human papillomavirus (HPV) is the main cause of cervical cancer. HPV is a common virus that is passed from one person to another during sexual intercoure. At least half of sexually active people will have HPV at some point in their lives, but few women will get cervical cancer. While the body’s immune system usually gets rid of the HPV infection naturally within two years, in a small percentage of people the virus can linger over time and turn some normal cells into abnormal cells and then cancer, according to the US CDC. In addition, having multiple sexual partners, poor hygiene, smoking are other factors that increase the risk of developing cervical cancer.
About Cervavac
The Cervavac vaccine is based on VLP (virus like particles), similar to the hepatitis B vaccine, and provides protection by generating antibodies against the HPV virus’s L1 protein. Experts have expressed hope that the DGCI approval will allow the government to procure enough HPV vaccines at a special price to vaccinate nearly 50 million girls aged 9–14 years in India who are waiting to receive the vaccine. This will be a huge step to accelerate cervical cancer elimination in India and globally.
Clinical trials commenced in early 2019, involving thousands of participants across 12 sites in the country. According to SII, phase III trials show a robust immune response in 100 percent of the vaccine recipients with excellent safety records.
How can vaccination help against cervical cancer?
Cervical cancer continues to be one of the only vaccine-preventable cancers. Screening and vaccination are two powerful tools that are available for preventing cervical cancer. HPV vaccines work best if administered prior to exposure to HPV. Therefore, to prevent cervical cancer WHO recommends vaccinating girls aged 9 to 14 years, when most have not started sexual activity. HPV vaccination is recommended for preteens aged 11 to 12 years, but can be given starting at age 9. HPV vaccine also is recommended for everyone through age 26 years, if they are not vaccinated already. It is not recommended for everyone older than age 26 years. However, some adults age 27 through 45 years who are not already vaccinated may decide to get the HPV vaccine after speaking with their doctor about their risk for new HPV infections and the possible benefits of vaccination. HPV vaccination in this age range provides less benefit, as more people have already been exposed to HPV. Some countries have started to vaccinate boys as the vaccination prevents HPV related cancers in males as well as.
HPV vaccination does not replace cervical cancer screening. Comprehensive cervical cancer control includes primary prevention (vaccination against HPV), secondary prevention (screening and treatment of pre-cancerous lesions), tertiary prevention (diagnosis and treatment of invasive cervical cancer) and palliative care. In countries where HPV vaccine is introduced, screening programmes population-based screening programmes are needed to identify and treat cervical pre-cancer and cancer to reduce cervical cancer incidence and deaths.
In 2016, a multidisciplinary expert group of the Indian Council of Medical Research (ICMR) reviewed available evidence globally regarding immunogenicity and efficacy, adverse effects and cost effectiveness of HPV vaccines, and recommended that adolescent girls should be vaccinated with two doses.
Challenges in the rollout of Cervavac
Screening and vaccination are two powerful tools that are available for preventing cervical cancer. Still, there is little awareness among women about the prevention of this cancer and less than 10 percent of Indian women get screened. All women aged 30-49 must get screened for cervical cancer even if they have no symptoms and get their adolescent daughters vaccinated with the HPV vaccine.
The biggest task facing the government in the rollout will be in allocating adequate resources and manpower for vaccinating the massive demographic of adolescent girls aged between 9 and 15, to ensure that they are protected from HPV early on. There is a huge need for stepping up awareness about the disease and the vaccine in the community.
It will be vital for the government to include Cervavac under the national immunization program. Discussions in this regards are reportedly underway and a decision is expected soon.
Conclusion
The World Health Assembly adopted the global strategy to accelerate the elimination of cervical cancer as a public health problem. The definition of elimination of cervical cancer has been set up as a country reaching the threshold of less than four cases of cervical cancer per 100,000 women per year. To reach this threshold by the end of 21st century, WHO has set up the following targets: 90 percent of girls fully vaccinated with HPV vaccine by age 15, 70 percent of women are screened with a high-performance test by 35, and again by 45 years of age and 90 percent of women identified with cervical disease receive treatment (90 percent of women with pre-cancer treated, 90 percent of women with invasive cancer managed).
In the Indian context, concerted efforts by both the government and the private sector will be needed to achieve these targets. Experts suggest that school-based vaccination programmes will work effectively. Currently, none exist and therefore planning will need to be done along those lines. Those accessing public health programmes will get the vaccine free of cost at government-aided schools. However, collaborative efforts will have to be made to ensure the involvement of private healthcare facilities and NGOs towards an effective rollout.
References
https://www.who.int/news-room/fact-sheets/detail/cervical-cancer
https://indianexpress.com/article/explained/hpv-vaccine-cervical-cancer-benefits-8031747/