Executives with Pfizer, Moderna say they're ramping up vaccine supplies

Executives with Pfizer and Moderna said the companies are ramping up their supply of coronavirus vaccines, with shipments expected to double and possibly triple in the coming weeks, in congressional testimony Tuesday.

In a prepared statement before a House subcommittee Tuesday, John Young, Pfizer's chief business officer, is expected to say the company plans to increase its delivery capacity of 4 million to 5 million doses a week to more than 13 million by mid-March.

Richard Nettles, the vice president of medical affairs at Johnson & Johnson, said the company plans to have enough of their single-dose Covid-19 vaccine for 20 million Americans by the end of March.

"We are confident in our plans to deliver 100 million single-dose vaccines to the United States during the first half of 2021, and we are continuing to partner with the U.S. government to explore all options to accelerate delivery," Nettles said in prepared remarks to the committee.

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Moderna expects to double its monthly delivery capacity to 40 million doses by April, according to Dr. Stephen Hoge, the company's president. Moderna has so far delivered 45 million doses, Hoge's testimony says.

Young attributed the increased supply to "significant investments" Pfizer made in several manufacturing sites and other improvements.

The U.S. surpassed 500,000 coronavirus deaths, and questions about equity in vaccine distribution persist. The Biden administration said this month that it was ramping up supplies to low-income communities and people of color who have been hit hard by the virus.

The Food and Drug Administration authorized emergency use of the vaccines, which use mRNA and are more than 90 percent effective after two doses, last year.