Pfizer says trials suggest Covid vaccine works against South African variant, is safe after 6 months

Pfizer and BioNTech said Thursday that trials suggest their vaccine is effective against a variant of the coronavirus that first appeared in South Africa, which some experts fear may escape existing vaccines.

The drugmakers also said in a statement that 12,000 people involved in their Phase 3 trial experienced high levels of protection from Covid-19 six months after their second dose, without any serious safety concerns.

“This is an important step to further confirm the high efficiency and good safety data that we have seen so far,” said Ugur Sahin, CEO and co-founder of BioNTech.

“These data also provide the first clinical results that a vaccine can effectively protect against currently circulating variants, a critical factor in achieving herd immunity and ending this pandemic for the global population.”

The vaccine, developed by US pharmaceutical giant Pfizer and its German partner BioNTech, received emergency use authorization from the Food and Drug Administration in December, which is only granted under special circumstances.

The results of Thursday’s trial will allow drugmakers to submit a full biologics license application to the FDA, Pfizer chief executive officer Albert Bourla said in the statement. They also plan to share the results with regulators around the world and submit the data for peer review.

The study included some 44,000 people, some of whom received the vaccine and others received a placebo. There have been 927 symptomatic cases of Covid-19, of which only 77 have received the vaccine – an effectiveness rating of 91.3%, according to the statement issued by an unpaired press release.

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Only one of 21 severe cases had received the vaccine – indicating an efficacy of 95.3%, the statement said, using the Food and Drug Administration’s definition of severity.

As defined by the Centers for Disease Control, there were no severe cases in the vaccinated group, indicating 100% effectiveness against severe illness, he said.

The CDC reported on Monday that the Pfizer and Moderna vaccines are extremely effective in the real world, reducing infections by 90% in fully vaccinated people.

The results are the first actual data from the United States and are consistent with similar research conducted in other countries.

Part of the trial took place in South Africa, where a variant first appeared – known as B.1.351 – that some scientists fear may escape existing vaccines.

There have been 312 identified cases of the strain in the United States, according to the latest figures from the CDC.

In the Pfizer-BioNTech trial, six cases of this variant were seen, but none of them were people who had received the vaccine – indicating 100% effectiveness, he said.

This was welcomed by drugmakers, as in February they said a lab test suggested their vaccine produced lower levels of antibodies to this strain.

Although the antibody levels were lower, “this does not appear to affect the high efficacy observed against this variant,” the statement said on Thursday.

It comes a day after companies said their Covid-19 vaccine was safe and effective in teens ages 12 to 15.

They plan to apply for emergency use authorization for these ages in the coming weeks.

Pfizer is also studying the effectiveness of the vaccine in children aged 6 months to 11 years. The first doses of this trial were administered last week.