Johnson & Johnson's newly authorized COVID-19 vaccine has started shipping and its top executive said on Monday that Americans should be able to receive the single-dose shot within the next 24 to 48 hours, adding a third vaccine in the United States.
The drugmaker plans to deliver 4 million vaccine doses this week, 20 million by the end of March and 100 million doses by June, J&J Chief Executive Office Alex Gorsky said in interviews with NBC News' Today program and CNBC.
"Within the next 24 to 28 hours, Americans should start receiving shots in arms. They're literally rolling out with the trucks as we speak," he said to NBC News.
J&J's vaccine requires only one shot, while other authorized vaccines require two.
"The faster we can get everybody vaccinated, the lower the chance for mutations and variants," Gorsky said in a CNBC interview.
The coronavirus has been circulating around the globe for more than a year and in recent months, new virus variants have arisen against which the J&J vaccine and others appear less effective. Public health officials say a global vaccination effort can help stem these variants from developing.
Gorsky said J&J was confident that its vaccine would have a "robust response" against these emerging variants, based on its clinical trial in countries including South Africa and Brazil where worrisome variants were circulating.
The company is developing a version of its vaccine to target the variant first found in South Africa, and will be ready to start late-stage trials by this summer.
Pfizer and German partner BioNTech and Moderna Inc have FDA-authorized two-dose vaccines.
Shares of J&J were up nearly 2% in premarket trading after the U.S. Food and Drug Administration gave it emergency use authorization on Saturday.
McKesson Corp said on Monday it had begun distributing the vaccine.
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