Novavax Covid-19 vaccine could be cleared for US use by May: CEO

Novavax can already manufacture its shots at scale and will be able to have tens of millions of doses stockpiled and ready to ship in US when it receives authorization, Erck said.

Novavax Inc's COVID-19 vaccine could be cleared for use in the United States as soon as May if U.S. regulators authorize it based on data from the company's British trial, which could be completed "in the coming weeks," its chief executive said on Monday.

However, Chief Executive Stanley Erck added that talks with the U.S. Food and Drug Administration are ongoing and the agency may require Novavax to submit data from its U.S. trial, which could take an additional two months to complete, pushing back U.S. clearance to mid-summer.

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Novavax shares were off 5.6% at $226.85 in extended trading after initially rising following release of its quarterly results. The shares have soared about 2,400% from $9.82 on Jan. 21, 2020, when the company announced it was developing a vaccine against the coronavirus.

Preliminary data from its UK trial released in January showed the vaccine to be around 96% effective against the original version of the coronavirus and around 86% effective against the now widely circulating variant first discovered in Britain.

Novavax can already manufacture its shots at scale and will be able to have tens of millions of doses stockpiled and ready to ship in the United States when it receives authorization, Erck said.

"It will be substantial - in the many tens of millions or a hundred million," Erck said in an interview.

Novavax had promised to deliver 110 million doses to the U.S. government by the end of the third quarter. That could happen as early as July, Erck said.

Novavax's vaccine production plants should all be fully functional by April, said Novavax research chief Gregory Glenn on a conference call after the company reported quarterly results.

"In April, May, June, we should be finishing filling and finishing product in advance of regulatory approvals," Glenn said.

In late January, Erck said he expected it would take several weeks for Novavax to file U.K. trial data with regulators in the United Kingdom, Europe and elsewhere. Novavax could produce up to 150 million doses per month by May or June, he had added in January in an interview.

The Novavax shot, if authorized, would add to the vaccine options for millions of Americans awaiting immunization against the coronavirus.

Johnson & Johnson's one-dose vaccine on Saturday become the third to win U.S. emergency use authorization (EUA). Vaccines produced by Pfizer Inc with partner BioNTech and Moderna Inc received EUAs in December.

Novavax's vaccine is a two-dose regimen like Pfizer's and Moderna's, but is easier to ship as it can be stored at refrigerator temperatures, rather than frozen.

Novavax promised to deliver doses to the United States after the Trump administration awarded it $1.6 billion to help finance research, development and production of a COVID-19 vaccine.

Novavax completed enrollment of its 30,000-subject U.S.-based trial in February.