India Approves AstraZeneca’s COVID-19 Vaccine, UK Begins Inoculations

India on Sunday granted emergency use approval for the COVID-19 vaccine co-developed by AstraZeneca (AZ) and Oxford University — formerly known as AZD1222 but now called COVID-19 Vaccine AstraZeneca — along with a separate vaccine, Covaxin, developed by Bharat Biotech.

India’s Serum Institute is manufacturing the AZ/Oxford vaccine domestically and expects to produce 300 million doses by July, according to the institute’s CEO Adar Poonwalla. This will be enough to vaccinate 150 million people with the two-dose vaccine — a small percentage of what will be needed to vaccinate India’s entire population of almost 1.4 billion.

The Indian government drew criticism for the Covaxin approval as the candidate only entered a phase 3 trial in mid-November (DID, Dec. 23, 2020) so it is too soon to have good data on the efficacy of a two-dose inoculation. Bharat Biotech is working with Malvern, Pa.-based Ocugen to develop Covaxin for the U.S. market.

India’s approval of the AZ/Oxford vaccine came just days after the UK government’s temporary approval issued Dec. 30, with vaccinations set to begin in Britain today. The UK’s approval of this vaccine has put increased pressure on regulatory authorities around the world to follow suit. As of Jan. 1, the UK is no longer a member of the European Union and the European Medicines Agency is not expected to approve the vaccine until at least February (DID, Dec. 30, 2020).

Moncef Slaoui, chief adviser to the Trump administration’s Operation Warp Speed, said last week he expects U.S. approval of the AZ/Oxford vaccine will not be granted until early April. Slaoui, however, did express optimism that the Johnson & Johnson single-dose vaccine, Ad26.COV2.S, could be approved in the U.S. in  the first half of February.

AstraZeneca has not yet submitted an application to the FDA for Emergency Use Authorization and is planning on filing in late January once it receives additional efficacy results (DID, Dec. 4, 2020). Still, multiple approvals of the AZ/Oxford vaccine are expected around the world this month. Argentina and El Salvador approved the vaccine for emergency use on Dec. 30.

On the supply front, the UK has ordered 100 million doses of the vaccine (DID, Nov. 5, 2020), while the U.S. has secured 300 million doses (DID, May 22, 2020) and the European Commission has ordered 300 million shots with an option for an additional 100 million (DID, Aug. 28, 2020).

Easier to ship and store than the already U.S. approved messenger RNA-based vaccines from Pfizer/BioNTech and Moderna, the low-cost AZ vaccine has clear advantages but also has some potential shortcomings. Its efficacy has yet to be fully demonstrated by final data from late-stage trials and AstraZeneca and Oxford University do not appear to be working from the same script when discussing the results publicly, which has caused confusion and concern over the vaccine’s best dosing regimen.

British regulators approved the vaccine as a two-dose regimen with two full doses, although phase 3 trial results published by Oxford researchers in The Lancet last month appeared to show higher efficacy in one subset of participants taking a half dose followed by a full dose (DID, Dec. 9, 2020).

The vaccine was said to demonstrate 90 percent efficacy for participants who received the one-and-a-half dose, while those who received two full doses showed only 62 percent efficacy. British regulators discounted the one-and-a-half dose data for the purposes of their temporary approval.

According to Oxford, it had discussed with regulators the phase 3 half-dose and received permission to update the trial protocol to follow the group receiving the low-dose followed by a full-dose regimen (DID, Dec. 10, 2020). But AstraZeneca has maintained that the one-and-a-half dose regimen was the result of a measurement error.

AstraZeneca CEO Pascal Soriot last week claimed that a “winning formula” of the vaccine is in the works, one that would put the vaccine in the same 95 percent efficacy realm as Pfizer’s and Moderna’s shots. But he did not offer details (DID, Dec. 29, 2020).

In recommending approval of the vaccine for adults 18 years and older, the UK’s Medicines and Healthcare products Regulatory Agency said the second dose of the vaccine should be administered between four to 12 weeks after the initial dose. The Pfizer/BioNTech vaccine requires second vaccinations in approximately three weeks and the wider window for second vaccinations with the AZ vaccine should ease some of the logistical burden on healthcare facilities. ― Jason Scott