The coronavirus vaccine developed by AstraZeneca and Oxford University will likely not be approved for use in the US until April, a top health official from the Trump administration said Wednesday.
“We expect that, if all goes well, the interrogation and emergency use clearance can be issued sometime in early April,” said Moncef Slaoui, the government’s chief science adviser for Operation Warp Speed.
Slaoui’s estimate for April is a change from earlier this month, when he told reporters he expected an emergency permit to come in February. The US has already bought 300 million doses of the vaccine.
Britain became the first country in the world to approve the emergency vaccine on Wednesday, but it was based in part on unpublished data because of the way the UK is evaluating the trial.
In an effort to get as many doses of the vaccine out as possible, British officials said they would not withhold the doses. Instead, they prioritize giving people the first dose and delay the second injection for three months.
The vaccine has the potential to make a global difference in the fight against COVID-19. AstraZeneca has pledged to make as many as three billion doses available by 2021, far more than any other manufacturer. The company has also pledged not to make a profit on the vaccine, so the cost is much cheaper too.
Unlike the two approved vaccines from Pfizer and Moderna, the vaccine can also be transported and stored for months under normal refrigeration.
In the US, however, health officials have been questioning after promising initial results turned out to be the result of a dosing error.
The shot has an effective rate of 62 percent when given in two full doses 28 days apart, as for most participants. The company found that the drug was 90 percent effective when a small group in the study was initially accidentally given half a dose, followed by a full dose.
Slaoui expressed some concern about the data, but indicated that the final decision would lie with the Food and Drug Administration (FDA).
“The biggest question mark, frankly, is its efficacy in the elderly population. That needs to be further documented, just because not enough … of the subjects were recruited to litigation,” Saloui said.
Slaoui also questioned the drug’s true efficacy. AstraZeneca has said the combined “pooled” numbers are on average 70 percent effective, but Slaoui said he thinks the FDA would not be satisfied with that statement.
“We need a clear and concrete number, more than a number that, you know, is collected by putting together different trials with different schedules and different materials,” Slaoui said.