he top US health agency on Monday granted full approval to Pfizer-BioNTech’s two-shot messenger RNA (mRNA) Covid-19 vaccine, making it the first for the United States.
It will now retail as Comirnaty (koe-mir’-na-tee).
Janet Woodcock, the acting head of the Food and Drug Administration (FDA), called the approval a “milestone”.
“While this and other vaccines have met the FDA’s rigorous, scientific standards for emergency use authorisation, as the first FDA-approved Covid-19 vaccine, the public can be very confident that this vaccine meets the high standards for safety, effectiveness, and manufacturing quality the agency requires of an approved product,” she said.
The full authorisation will address reservations harboured by people who refused to be vaccinated citing Emergency Use Authorization (EUA) granted to all Covid-19 vaccines available in the United States thus far. It will allow the company to retail the vaccine more freely, through pharmacies and also advertise it.
Pfizer-BioNTech s Covid-19 vaccine was the first to be used in the United States (it had been rolled out already in the United Kingdom and Canada), after the FDA granted it EUA on December 11, 2020 for people 16 years of age and older. Its rollout was a national event, reported breathlessly from the first truck that left the company’s plant in Portage, Michigan on December 13, to the administering of the first shot to a healthcare worker at a New York hospital on December 14.
Since then, more than 204 million of the Pfizer shots have been administered, according to data compiled by the Centers for Disease Control and Prevention.
The EUA approval for Moderna’s two-shot vaccine, also based on mRNA technology followed shortly and then Johnson & Johnson’s one-shot vaccine. AstraZeneca’s vaccine, which is used in India as Covishield, has still not been authorised for use, not even emergency one.
The FDA says it grants emergency use authorisation during public health emergencies to make available medical products that may be “effective in preventing, diagnosing, or treating a disease, provided that the FDA determines that the known and potential benefits of a product, when used to prevent, diagnose, or treat the disease, outweigh the known and potential risks of the product”.
For full authorisation for Comirnaty, the FDA said it analysed data from about 20,000 vaccine and 20,000 placebo recipients between the ages of ages 16 and older who did not have evidence of the Covid-19 virus infection within a week of receiving the second dose.
Its safety was evaluated in approximately 22,000 people who received the vaccine and 22,000 people who received a placebo 16 years of age and older, the agency said.
The vaccine was found to be 91% effective in preventing Covid-19, according to the clinical trial data. More than half the participants of the clinical trial were followed for four months and an estimated 12,000 for six months.
The most common side-effects of Comirnaty were pain, redness and swelling at the injection site, fatigue, headache, muscle or joint pain, chills and fever. “The vaccine is effective in preventing Covid-19 and potentially serious outcomes including hospitalisation and death,” said the FDA.
The agency also evaluated the data for myocarditis and pericarditis. It has been “determined that the data demonstrate increased risks, particularly within the seven days following the second dose”, the FDA said. The risk is higher among males under 40 compared to females and older males; and it was the highest in males 12 through 17 years of age.
Though the data showed most individuals have had resolution of symptoms, some people had to be administered intensive care support, the agency said further. These risks will be included in the Comirnaty Prescribing Information. “Information is not yet available about potential long-term health outcomes,” the FDA said.