Which COVID-19 vaccines are licensed in India?
Covishield® (AstraZeneca’s vaccine manufactured by the Serum Institute of India) and Covaxin® (manufactured by Bharat Biotech Limited) are the two vaccines that have been granted emergency use authorization (EAU) by the Central Drugs Standard Control Organization in India.
What is Emergency Use Authorization (EUA)/ Permission for restricted use?
Emergency Use Authorization (EUA) is a regulatory mechanism to facilitate the availability and use of vaccines and medicines to prevent and/or reduce the impact of life-threatening diseases or conditions during public health emergencies as caused by COVID-19. The Food And Drug Administration (FDA) allows the use of unapproved medical products or unapproved uses of approved medical products during emergency situations to diagnose/treat or prevent such diseases, especially when there are no approved and available alternatives.
The concept of EUA has always existed to save the lives of people. However, before the grant of the EUA, rigorous assessments of laboratory and clinical trial data, including data on quality, safety, production of protective antibodies and efficacy is conducted. Safety is a particularly critical aspect of this scrutiny and a risk-versus-benefit evaluation is done in the context of a public health emergency. Full licensure is obtained when the manufacturer submits the complete data. EUA by Indian regulators is aligned with global guidelines.
Previously, EUAs have been granted vaccines for the outbreak of Anthrax, Ebola, Enterovirus, H7N9 Influenza, and Middle East Respiratory Syndrome. As of January 2021, nine COVID-19 vaccines were in emergency use in numerous countries around the globe.
Have the vaccines undergone clinical trial before the EUA?
Both the COVID-19 vaccines have completed their Phase I and II trials. Covishield® has completed its Phase III trials in the UK and the bridging trial in India.
What is Phase I, II and III of the clinical trial for a vaccine?
Clinical trials are a way to test new methods of diagnosing, treating, or preventing health conditions.
Vaccine trial phases include:
Pre-clinical: Vaccine development in laboratory animals Phase 1 Clinical trial (small number of participants): Assess vaccine safety, immune response and determine right dosage (short duration)
Phase 2 Clinical trial (few hundred participants): Assess safety and the ability of the vaccine to generate an immune response (short duration)
Phase 3 Clinical trial (thousands of participants): Determine vaccine effectiveness against the disease and safety in a larger group of people (duration 1-2 years)
Why is vaccination not provided to children?
COVID-19 affects all age groups. Children who rarely have severe COVID-19 symptoms, have not yet been tested for any experimental coronavirus vaccine. However, the rate of morbidity and mortality are several times higher in adults, particularly those above the age of 50 years with comorbidities. Children may have either an asymptomatic or mild infection. The general practice is to first evaluate any new vaccine in an older population and then age reduction is done to assess the safety and effectiveness in the paediatric population. There are some clinical trials underway to test the effectiveness and safety of the COVID-19 vaccines in children.
What technology has been used in the development of the currently available two vaccines?
Covishield® vaccine is a Viral Vector based technology which is also used to manufacture Ebola vaccines.
Covaxin® vaccine is a whole-Virion Inactivated Coronavirus vaccine, which is also used to manufacture vaccines like Influenza, Rabies and Hepatitis A.
What is the composition of both the vaccines?
The composition of Covishield® includes inactivated adenovirus with segments of Coronavirus, Aluminium Hydroxide Gel, L-Histidine, L-Histidine Hydrochloride Monohydrate, Magnesium Chloride Hexahydrate, Polysorbate 80, Ethanol, Sucrose, Sodium Chloride, and Disodium Edetate Dihydrate (EDTA).
The composition of Covaxin® includes inactivated Coronavirus, Aluminium Hydroxide Gel, TLR 7/8 Agonist, 2-Phenoxyethanol and Phosphate Buffered Saline [NKA1].
How are the two vaccines stored? How has the cold chain been maintained during the storage and transportation of vaccines?
Both vaccines do not require sub-zero storage, no reconstitution requirement, and ready to use liquid presentation in multi-dose vials, stable at 2-8 degrees Celsius.
For COVID-19 vaccine storage, 29000 cold chain points, 240 walk-in coolers, 70 walk-in freezers, 45000 ice-lined refrigerators, 41000 deep freezers and 300 refrigerators are used.
If I have received the vaccine as a health worker, how will my family members receive the vaccine (as they are exposed as well)?
The people at the highest risk of exposure such as health care and frontline workers will receive the vaccine on priority. These groups are also a likely source of infection of their family members. Other family members will be vaccinated according to the age-specific prioritization stated by the Government of India.
What is the dosing schedule of both vaccines?
The interval between two doses of the Covishield® vaccine has been extended from four-six weeks to 12 weeks.
The second dose of Covaxin® can be taken four to six weeks after the first dose.
Do I get to choose which vaccine I will receive?
With India expanding its vaccine drive, people between the age group of 18-44 years, who are eligible for inoculation on May 1, can choose their preferred vaccines at private centres. Till April 30, beneficiaries did not have the option to choose between the two available vaccines. The choice of vaccines is applicable only for private centres, where people pay for the jabs.
How was it possible for scientists to develop a vaccine against the novel coronavirus in such a short time?
Developing a vaccine generally involves years of research. But the development process of vaccines against novel coronavirus was accelerated substantially without compromising on safety. The vaccine has to undergo several phases of clinical trials. It is first evaluated in animals and then humans.
The world was able to develop COVID-19 vaccines so quickly because of years of previous research on related viruses, enormous funding that allowed firms to run multiple trials in parallel and regulatory approvals which used to take several months have been fast-tracked. It helped eliminate all the time lapses between the pre-clinical and clinical trial stages.
Is a COVID-19 vaccine scheduled anytime soon for me? Will it be given to everyone simultaneously?
The vaccination drive in India was segregated based on priority groups who were at a higher risk. The first phase of the vaccination drive was flagged off on January 16th for the healthcare and frontline workers. It was gradually expanded to the second phase to accommodate persons over 60 years of age (as of January 1st, 2021) and persons between 45 and 59 years with comorbid conditions from March 1st, 2021. Those who are above 45 years of age will be able to take the vaccination from April 1st, 2021. On May 1st, India opened the inoculation drive to everyone between the age group of 18-44 years. Now, India is one of the few countries who has opened vaccination for all adults.
Is it mandatory to take the vaccine?
Vaccination for COVID-19 is a voluntary exercise. However, it is advisable to receive the complete schedule of the COVID-19 vaccine to increase immunity, protect oneself against this disease and also to limit the spread of this disease to close contacts including family members, friends, relatives and co-workers.
Will the vaccine be safe since it has been tested and introduced in a short span of time?
The vaccine has been introduced in the country only after the regulatory bodies cleared it based on its safety and efficacy.
Out of the multiple vaccines available, how is one or more vaccines chosen for administration?
The safety and efficacy data from clinical trials of vaccine candidates are examined by the Drug Regulator of our country before granting them license. Thus, all the COVID-19 vaccines that receive license will have comparable safety and efficacy. However, it must be ensured that the entire schedule of vaccination is completed by only one type of vaccine as different COVID-19 vaccines are not interchangeable.
Are the vaccines introduced in India as effective as the ones introduced in other countries?
Yes, the COVID-19 vaccines introduced in India are as effective as any vaccine developed by other countries. Various phases of vaccine trials are undertaken to ensure its safety and efficacy.
Indian regulators have given authorization to Covaxin even before its Phase 3 trial results were out. How do we explain this?
We are passing through a COVID-19 pandemic that has caused social disruption, economic downturn and a significant number of deaths. To control this pandemic, the society, as well as the system, may have to take steps that may also be termed as drastic.
The Drug Controller General of India (DCGI) granted permission for restricted emergency use of the Bharat Biotech COVID-19 vaccine - Covaxin. Since it was still undergoing phase-3 clinical trials, the vaccine has raised some questions. As phase 1 and 2 clinical trials demonstrated that the vaccine is safe and provides robust immune response, the phase 3 efficacy trial was initiated.
However, to what extent the vaccine will protect the recipients from getting the disease is not fully known yet. Therefore, the regulators have allowed its use in trial mode.