Updated: Dec 24, 2020, 15:44 IST
While the United States on Wednesday secured a deal with Pfizer Inc. for an additional 100 million doses of its Covid-19 vaccine, the cases of allergic reactions have reportedly prompted discussions between vaccine makers and the National Institutes of Health (NIH) to run clinical trials in very allergic populations. According to a CNN report, US President Donald Trump’s Covid-19 vaccine czar said that the frequency of allergic reactions to Pfizer’s vaccine is greater than expected.
“That frequency, as it stood yesterday (December 22), is superior to what one would expect with other vaccines,” Dr Moncef Slaoui, chief scientific adviser for Operation Warp Speed, was quoted as saying by the US media network.
The UK regulators have already issued an advisory regarding the issue, urging people who have a history of “significant” allergic reactions to not get the Pfizer-BioNTech vaccine. The Medicines and Healthcare products Regulatory Agency (MHRA) issued precautionary advice to the National Health Service (NHS) after two health care staff members experienced allergic reactions. Dr June Raine, chief executive of the MHRA, had testified to a parliamentary committee where she acknowledged that the cases of allergic reactions didn’t feature in the extensive clinical trials.
“We know from the very extensive clinical trials that this wasn’t a feature. But if we need to strengthen our advice, now that we’ve had this experience in the vulnerable populations – the groups have been selected as a priority – we get that advice to the field immediately,” said Dr Raine.
The United States has started the immunisation drive against the coronavirus disease after the Food and Drugs Administration (FDA) granted emergency use authorisation to Pfizer-BioNTech, followed by Moderna. Under the new agreement for additional doses of Pfizer’s Covid-19 vaccine, the US drugmaker and its German partner BioNTech will deliver at least 70 million doses by June 30, with the remaining doses to be delivered no later than July 31.