All you need to know about SII’s Covishield and Bharat Biotech’s Covaxin

The government on Saturday will launch one of the world's biggest vaccination programmes with shots manufactured in India - one developed by Oxford University and AstraZeneca Plc, the other by Bharat Biotech International Ltd with a state-run institute.

Besides that, Prime Minister Narendra Modi would launch the country’s Covid-19 vaccination drive on the same day via video conferencing. Meanwhile, adequate doses of the two made-in-India vaccines have been delivered to all the states and Union Territories.

As the Centre paves the way for a massive inoculation drive, here are some of the facts about the two vaccines selected by the Drugs Controller General of India (DCGI):

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Manufacturing

Covishield coronavirus vaccine has been developed by Oxford University in collaboration with AstraZeneca. In India, Pune-based Serum Institute of India (SII), the world's largest vaccine manufacturer, has a licence to produce the shot.

On the other hand, Covaxin is developed by Hyderabad-based Bharat Biotech. It is also India’s first indigenous vaccine against the virus. The Hyderabad-based pharma has developed the vaccine with the help of the Indian Council of Medical Research (ICMR) and National Institute of Virology.

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How were the vaccines developed?

The vaccine - known either as ChAdOx1 or AZD1222 - is made by taking a common cold virus called an adenovirus from chimpanzees and deleting about 20% of the virus’s instructions. The vaccine also follows the genetic instructions programmed into it by its developers to successfully provoke a strong immune response.

Bharat Biotech's Covaxin is made of an inactivated vaccine that kills the live microorganisms of the coronavirus. This vaccine destroys the ability of the virus to multiply in the human’s body and increases immunity system to fight the virus.

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How effective are they?

The Covid-19 vaccine developed by AstraZeneca and Oxford University showed an average efficacy of 70.4 per cent in a pooled analysis of interim data from late-stage trials. The results published in The Lancet medical journal showed the candidate vaccine's efficacy was 62% for those given two full doses, and 90 per cent in a sub-group of trial participants given a half then a full dose.

Meanwhile, Bharat Biotech has conducted all the three trials on 23,000 volunteers across India. However, the number was about 3,000 people short of the target number of volunteers set by the Indian Council of Medical Research (ICMR). The DCGI is confident that the vaccine has been found effective.

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Controversy related to the two vaccines

The Serum Institute of India had to pause its trials of the Covishield vaccine following a setback related to complaints of side-effects during AstraZeneca's phase 3 trials. It called the move to pause the trial "a routine action”. However, the company resumed its trials a few days after that.

A huge controversy had broken out on the permission accorded to Hyderabad-based Bharat Biotech’s home-grown vaccine that was given the nod without any efficacy data in violation of standard clinical practice. While approving the emergency use, the DCGI has asked Bharat Biotech to submit safety data in every 15 days for the first two months and once in a month after that period.

Cost of the vaccines

The government had placed an order with SII for 11 million doses of its vaccine each costing Rs 210 including GST. According to the order, each dose of the vaccine has been priced at Rs 200 and with GST of Rs 10, it would cost Rs 210.

The Centre is procuring 55 lakh doses of Covaxin from Bharat Biotech India Limited. "For 38.5 lakh doses, the price is Rs 295 each, excluding taxes. Bharat Biotech is providing 16.5 lakh doses for free which ultimately brings the cost of each dose of Covaxin down to Rs 206," Union Health Secretary Rajesh Bhushan had said.

Side effects

For Covishield, possible adverse events following immunisation (AEFIs) are: injection site tenderness, injection site pain, headache, fatigue, myalgia, malaise, pyrexia, chills and arthralgia, and nausea.

Very rare events of demyelinating disorders have been reported following vaccination with this vaccine without the causal relationship establishment.

For Covaxin, AEFIs include injection site pain, headache, fatigue, fever, body ache, abdominal pain, nausea and vomiting, dizziness-giddiness, tremor, sweating, cold, cough and injection site swelling.