The coronavirus vaccine manufactured by the University of Oxford in the United Kingdom could be rolled out for public use by the end of the year, but there is no certainty that will happen, the lead developer of the vaccine Sarah Gilbert said on Tuesday, Reuters reported quoting her statements to BBC Radio.

British medical journal The Lancet said in a study on Monday that the vaccine, called AZD1222, has been found to be safe, and produced an immune response in early-stage clinical trials in healthy volunteers. “The end of the year target for getting vaccine roll out, it’s a possibility but there’s absolutely no certainty about that because we need three things to happen,” Gilbert said.

Gilbert said the vaccine needs to work in late-stage trials. Large quantities need to be produced, and regulators have to agree to licence it quickly for emergency use, she added. “All of these three things have to happen and come together before we can start seeing large numbers of people vaccinated,” she said. Scientists at Oxford aim to produce 10 lakh doses by September. One of the hurdles to this is the low incidence of infection in the United Kingdom.

Late-stage trials of the vaccine have begun in South Africa and Brazil and are slated to start in the United States soon. John Bell, a professor of medicine at the university, said: “The crucial thing is that we get enough people exposed to the virus who’ve also had the vaccine that we can actually get some proper adjudication of whether it prevents the disease and remains safe.”

British researchers first tested the vaccine on about 1,000 people in April, half of whom were given the dose and the other half a placebo. On Monday, scientists said they found that the experimental vaccine produces a dual immune response in persons aged 18 to 55.

The vaccine has been produced by British-Swedish multinational pharmaceutical and biopharmaceutical company AstraZeneca. The company has signed agreements with many governments to supply the vaccine, should it be found to be effective and gain regulatory approval. AstraZeneca claims that it will not seek to profit from the vaccine, and is already committed to making 200 crore doses.

In India, human trials of Covaxin, the first indigenous vaccine against the coronavirus, began in Delhi and Goa on Monday. India on Tuesday added 37,148 new cases, taking its total count to 11,55,191. The toll rose by 587 to 28,084. The total active cases are now more than 4 lakh.

Globally, over 1.4 crore people have so far been diagnosed with the infection, and more than 6.1 lakh have succumbed to it, according to the Johns Hopkins University. Over 83 lakh people have recovered.

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