AstraZeneca Plc remains committed to getting U.S. emergency clearance for its coronavirus vaccine whose public acceptance has been undercut by a series of missteps and potentially serious rare side effects.

The U.K. drugmaker, which has pledged not to profit from its COVID shot during the pandemic, said it’s still seeking an emergency use authorization in the first half of 2021 and working with U.S. officials on the filing. Astra had said earlier that it would apply for the authorization by mid-April.

The vaccine, developed with the University of Oxford, sold US$275 million in the first quarter, Astra reported Friday, a fraction of its US$7.3 billion in revenue. Meanwhile, Pfizer Inc. has forecast US$15 billion in 2021 sales from the COVID vaccine made with partner BioNTech SE, while Moderna Inc. expects to reap about US$18 billion.

A year after Astra and Oxford announced their partnership, the pharma company said it has provided more than 300 million doses of the vaccine to 165 countries. But it has yet to gain approval in the U.S. Backing from the Food and Drug Administration could help with the perception of the vaccine in light of reports of blood clots seen as a very rare side effect.

“We never pretended that we were going to be perfect and certainly we’ve learned a few things along the way,” Chief Executive Officer Pascal Soriot said on a call with reporters. “But you have to realize that what we’ve done has been done within a year.”

First-Quarter Results

Astra’s quarterly results exceeded analysts’ estimates as the company benefited from strong growth in its vaunted portfolio of cancer drugs. Adjusted earnings climbed to US$1.63 a share, while sales increased 15 per cent. The shares rose as much as 4.5 per cent in London, the most intraday since November.

Development of Astra’s vaccine has been fraught with concern, especially in the U.S., where use may be further delayed after the White House announced its entire supply would be shared with other countries. The decision would make as many as 60 million vaccine doses available for export in the coming months.

The delay in authorization is partly due to disparate data from various trials and real-world use of the shot, and raises the possibility it could miss the window to qualify for emergency status given the pace of the U.S. rollout.

“The assumption is we will be filing” for authorization, Mene Pangalos, Astra’s head of biopharmaceuticals research, told reporters on the call. The company will pursue the usual non-emergency approvals path if necessary, he said.

Astra’s vaccine accounts for 90 per cent of India’s shots and 98 per cent of supplies for Covax, the World Health Organization-backed program to deploy immunizations all over the world, Soriot said.

Acquisition on Track

The company had to row back its initial U.S. trial results last month after an independent monitoring panel raised concerns the data was ‘outdated’. Astra followed up with a more in-depth analysis of the more than 32,000-person trial two days later that moved the efficacy from 79 per cent to 76 per cent. The shot showed 100 per cent efficacy against severe disease and hospitalization in both reviews, and was 85 per cent effective in people aged over 65.

Astra also plans to report data and apply for regulatory approval for its COVID-19 antibody by July, which is being tested to both prevent and treat the disease.

Completion of the US$39 billion takeover of rare-disease specialist Alexion Pharmaceuticals Inc. in the third quarter is on track, Astra said. The U.S. Federal Trade Commission gave the go-ahead for the deal this month.