Less than a week after the launch of the world’s largest inoculation campaign, India dispatched tens of thousands of free doses of Covid-19 vaccines to neighboring countries in what is being widely described as “vaccine diplomacy”.
The Indian drug regulator gave the green light to Covishield (the local name for the Oxford-AstraZeneca vaccine developed in the UK) and Covaxin, produced locally by pharmaceutical company Bharat Biotech.
India is a vaccine powerhouse: it produces 60% of the world’s vaccines and is home to half a dozen major manufacturers.
So, what do we know about vaccines in India?
How does Covaxin work?
The vaccine supported by the local government was developed by Bharat Biotech, a 24-year-old vaccine manufacturer, which has a portfolio of 16 vaccines and exports to 123 countries.
It is an inactivated vaccine, which means that it is composed of dead coronaviruses, which makes it safe to be injected into the body. Bharat Biotech used a sample of the coronavirus, isolated by the National Institute of Virology in India.
When administered, immune cells can still recognize the dead virus, causing the immune system to produce antibodies against the pandemic virus.
Both doses are administered four weeks apart. The vaccine can be stored between 2C and 8C.
Bharat Biotech says it has a stock of 20 million doses of Covaxin and aims to manufacture 700 million doses of its four facilities in two cities by the end of the year.
What is the controversy surrounding Covaxin?
It all started when the regulator said the vaccine had been approved for “restricted use in emergency situations of public interest as an abundant precaution, in clinical trial mode, especially in the context of infection by mutant strains”.
Experts wondered how a vaccine was released for emergency use by millions of vulnerable people when testing was still in progress.
Both the manufacturer and the drug regulator say that Covaxin is “safe and provides a robust immune response”.
But the All India Drug Action Network said it was “perplexed to understand the scientific logic” to approve “an incomplete studied vaccine”. He said there were “intense concerns about the lack of efficacy data”.
Bharat Biotech defended the approval, saying that Indian clinical trial laws allowed “accelerated” authorization for drug use after the second phase of testing for “unmet medical needs for serious and fatal illnesses in the country”. He promised to provide efficacy data for the vaccine by February.
What about Covishield?
The Oxford-AstraZeneca vaccine is being manufactured locally by the Serum Institute of India, the world’s largest vaccine manufacturer. He says he is producing more than 50 million doses a month.
The vaccine, known as Covishield, is produced from a weakened version of a chimpanzee’s common cold virus (known as adenovirus). It has been modified to look more like the coronavirus – although it cannot cause disease.
When the vaccine is injected into a patient, it stimulates the immune system to start producing antibodies and prepares it to attack any coronavirus infection.
The vaccine is administered in two doses administered at an interval of four to 12 weeks. It can be safely stored at temperatures from 2 ° C to 8 ° C, almost the same as a home refrigerator, and can be delivered in existing healthcare environments, such as doctor’s offices.
This makes it easier to distribute than some of the other vaccines.
The jab developed by Pfizer-BioNTech, which is currently being administered in several countries, must be stored at -70C and can only be moved a limited number of times – a particular challenge in India, where summer temperatures can reach 50C.
How effective is Covishield?
International clinical trials of the Oxford-AstraZeneca vaccine showed that when people received half a dose and then a full dose, the effectiveness reached 90%.
But there was insufficient clear data to support the half-dose and full-dose idea.
However, unpublished data suggest that leaving a longer interval between the first and second doses increases the overall effectiveness of the vaccine – in a subgroup that received the vaccine in this way, it was 70% effective after the first dose.
Serum Institute (SII), Indian manufacturers of the vaccine, say Covishield is “highly effective” and backed by phase III test data from Brazil and the UK. Clinical trials are a three-step process to determine whether the vaccine induces good immune responses and whether it causes any unacceptable side effects.
But the patient rights group, All India Drug Action Network, says its approval was rushed because the manufacturer has not completed a “binding study” of the vaccine in Indians.
The company said it will try to conduct the bridge test of the vaccine in India in February. Some experts say there is no reason to suspect that it will not work as well, as the clinical trials already completed included a variety of ages and ethnicities.
Any other vaccine candidates?
The other candidates who are at different stages of testing in India to test safety and effectiveness include:
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A vaccine being developed by Biological E, based in Hyderabad, India’s first private vaccine manufacturing company, in collaboration with Dynavax and Baylor College of Medicine, United States
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HGCO19, India’s first mRNA vaccine made by Genova, based in Pune, in collaboration with the Seattle-based HDT Biotech Corporation, using pieces of genetic code to cause an immune response
Which countries are applying for vaccines in India?
Some of the first doses have already been sent to Bhutan, Maldives, Bangladesh, Nepal, Myanmar and Seychelles.
Only Covishield has been exported so far – some in the form of “gifts” and the rest in line with trade agreements signed between Serum and these nations.
In June last year, AstraZeneca reached a licensing agreement with Serum to supply one billion doses to low and middle income countries, with a commitment to supply 400 million before the end of 2020.
India is also planning to send doses to Sri Lanka, Afghanistan and Mauritius, following regulatory authorizations from those countries. It also released commercial exports of the Covishield vaccine to Brazil.
The Ministry of Foreign Affairs says that India will continue to supply vaccines worldwide, taking into account domestic requirements and international demands and obligations.