UK study for allergic reactions associated with Pfizer vaccine

London – British regulators warned Wednesday that people who had previously had severe allergic reactions should not receive the new Pfizer-BioNTech vaccine as they look at two side effects that occurred on the first day of the country’s mass vaccination program.

The UK Medicines and Health Products Regulatory Agency is investigating whether the reactions are vaccine-related. The two people involved were employees of the National Health Service who had a history of allergies and both were recovering. Authorities did not detail what their reaction was.

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Meanwhile, the regulator issued a warning to anyone who had a significant allergic reaction to a vaccine, medication, or food. This includes anyone who has had to wear an adrenaline rush or others who have had potentially fatal allergic reactions.

“Like the new vaccines, the MHRA has advised, as a precaution, that people with a major allergic reaction should not receive this vaccine after two people with a major allergic reaction reacted adversely yesterday,” said Professor Stephen Powis, medical director for the UK NHS. in a communication. – They’re both recovering well.

The medical regulatory agency also said vaccinations should not be carried out in facilities that do not have resuscitation equipment.

Pfizer and BioNTech said they are working with investigators “to better understand each case and its causes”.

Studies in the late stages of the vaccine “found no serious safety concerns,” the companies said. In these studies, more than 42,000 people received two doses.

“In the pivotal phase III clinical trial, this vaccine was generally well tolerated, with no independent safety concerns reported by the independent data monitoring committee,” the companies said.

Documents published by the two companies showed that people with a history of severe allergic reactions were excluded from the studies and doctors were advised to monitor such reactions in study participants who were not previously known to have severe allergic reactions.

New vaccines and medicines need to be closely monitored by health authorities, even in emergencies, because tests on tens of thousands of people are unable to detect the rare risk of 1 million 1

Dr Peter Openshaw, a professor of experimental medicine at Imperial College London, said there was “very little” chance of an allergic reaction to any vaccine.

The MHRA last week granted an emergency license for the Pfizer-BioNTech vaccine, making Britain the first country to allow its widespread use.

The UK launched a mass vaccination program on Tuesday, offering the shot to people over the age of 80, staff at a nursing home and some NHS workers. It is not clear how many have received jab so far.

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As part of the vaccine’s emergency approval, the MHRA has required healthcare workers to report potential side effects so that regulators can gather more information about safety and effectiveness.

The agency is closely monitoring the introduction of the vaccine and “is now investigating these cases in more detail to understand whether allergic reactions are vaccine-related or accidental,” he said. “The fact that we know about these two allergic reactions so soon, and that the regulator has taken steps to issue precautionary advice, shows that this monitoring system is working well.”

Dr June Raine, head of the medical regulatory agency, briefed the parliamentary committee on the reactions to previously planned testimonies about the pandemic.

“We know from very extensive clinical trials that this was not a feature of the vaccine,” he said. “But if we need to strengthen our advice, now that we have gained that experience in the vulnerable population, in priority groups, we get that advice right away.”

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