A handout picture shows the manufacturing process of the Pfizer-BioNTech COVID-19 vaccine with the implementation of the first step with the active ingredient mRNA in a production facility in Marburg, about 90 km north of Frankfurt.

BioNTech | via Reuters

Drug makers are ramping up Covid-19 vaccine production after working out manufacturing issues that initially delayed initial shots, executives told Congress this week.

Rep. Diana DeGette, D-Colo., Said Tuesday that “the amount of supply has fallen below expectations” as lawmakers urged Pfizer and Moderna executives about why they missed early US vaccine delivery targets .

Albert Bourla, CEO of Pfizer, said in October that the company could dispense between 30 and 40 million doses by the end of the year, but the company only hit the low end of that target last week, DeGette said at a House Committee hearing Energy and trade.

“We initially had some problems with the initial start-up of our vaccine,” said John Young, Pfizer’s chief business officer, at the hearing. “Together with other panellists, we developed a manufacturing process for a vaccine product that we’ve never made before.”

Young said the shortage of some raw materials was among the early production restrictions, but added that the company was on track to deliver 300 million doses of the two-shot vaccine before the end of July.

Rep. Jerry McNerney, D-Calif., Also interviewed Moderna for failing to meet initial delivery projections. The President of Moderna, Dr. Stephen Hoge, defended the company’s progress, noting it narrowly missed its goal of delivering 20 million doses by the end of last year. Moderna had delivered 17.8 million cans by December 31.

“In the end, when we tried to make these estimates, we never produced cans of this size,” said Hoge at the hearing. “We had a lot to learn along the way, and a lot of the challenges we encountered were the normal training experiences when you train people to use a complicated process.”

He added that the company was “very pleased” with its current production rate and that it dispensed 9 million cans last week and is on track to double its current production pace.

New manufacturers

Manufacturers of other vaccines that have not yet received Food and Drug Administration approval also said they are ready to quickly provide doses if approved in the United States

Johnson & Johnson’s Vice President of Medical Affairs, Dr. Richard Nettles said that if the company is approved for use in the US, it plans to ship more than 20 million doses to the federal government by the end of March. An FDA panel meets on Friday to review data on the one-shot vaccine. These could be approved as early as this week.

Dr. Ruud Dobber, president of AstraZeneca’s biopharma business, said the company expects to receive regulatory approval from the FDA for its two-shot vaccine in early April. He said the company had made enough cans to “release 30 million cans immediately” and up to 50 million by the end of April. The company will then produce between 15 and 25 million cans each month until it meets its 300 million can commitment, Dobber said.

And John Trizzino, Novavax’s chief commercial officer, said his company was ready to ship 100 million doses of its Covid-19 vaccine by the end of June, once it receives emergency clearance.

“Variant vaccine”

Executives said they believe the vaccines currently available are still effective against the emerging threat of new mutant variants of the coronavirus, but they have all started testing booster shots or preparing to target them to use.

The FDA released new guidance on Monday to clarify to vaccine manufacturers what the regulatory process will be for potential Covid-19 booster shots targeting new variants. The agency said no lengthy clinical trials are required, but instead companies can request changes to their existing applications for emergency use approval.

“We have had productive discussions with the FDA,” said Moderna’s Hoge. “Ultimately, it is their responsibility to set the bar and make recommendations on whether the vaccine against these new variants is effective and safe. However, we hope we can do this without large, randomized phase three trials.”

Pfizers Young reiterated Hoge, saying that the process should be “more like a seasonal flu-like process,” meaning fewer patients will have to participate in the clinical trials.