By Dave Simpson

Law360 (March 2, 2021, 10:36 PM EST) -- President Joe Biden said Tuesday that a manufacturing partnership between Johnson & Johnson and Merck, arranged by activating the Defense Production Act, will boost coronavirus vaccine supplies enough by the end of May to jab every U.S. adult.

The deal will expand production of J&J's COVID-19 vaccine and, when combined with supplies from Pfizer-BioNTech and Moderna vaccines, allow Biden to deliver the vaccines two months earlier than last promised.

"Three weeks ago, I announced we would have enough vaccine supply for all Americans by the end of July," he said on Twitter. "Now, with our efforts to ramp up production, we will have enough vaccines for every American by the end of May."

The U.S. Department of Health and Human Services will work with Merck to repurpose some of the pharmaceutical giant's existing facilities for rapid large-scale manufacturing of vaccines, HHS said in a release on Tuesday.

Janssen Pharmaceuticals, a unit of J&J, will use the repurposed Merck facilities to manufacture the vaccine, while Merck will use two facilities to undertake other aspects of the production, HHS said.

HHS will pay Merck $105 million for the task.

"These efforts will contribute to J&J's ability to accelerate delivery of their vaccine doses from 100 million doses by the end of June to at or near 100 million doses by the end of May," HHS said in a release. "In the long term, these actions will ultimately double J&J's U.S. capacity to produce drug substance and increase the U.S. capacity for fill-finish."

J&J said its vaccine has an overall efficacy rate of 72% in the U.S. and is 86% effective at preventing severe cases. The company also said the data shows the vaccine offers complete protection against hospitalization and death.

J&J submitted its application for emergency use authorization to the U.S. Food and Drug Administration on Feb. 4 and received approval on Saturday. The submission included data from a Phase 3 clinical study involving about 43,800 participants, of which 468 became symptomatic. There were no significant safety concerns with the vaccine, though a small number of individuals developed fevers, J&J said.

The vaccine's effectiveness varied from country to country but was shown to be 66% effective globally 28 days after vaccination and 85% effective at preventing severe disease.

On day 14, the data shows that the J&J vaccine reached a 67% rate of efficacy globally and 74% in the U.S. study.

On Dec. 10, the FDA gave its first stamp of approval to a COVID-19 vaccine when it signed off on an emergency use authorization request from Pfizer and its German partner BioNTech. The first doses of that vaccine were administered to front-line health care workers in the U.S. later that month. The Pfizer-BioNTech two-dose vaccine is about 95% effective.

Moderna filed its emergency authorization request in late November. The FDA approved its vaccine, which is 94% effective at preventing infection among individuals 18 and older, in mid-December.

While the Pfizer-BioNTech and Moderna vaccines are more effective, the J&J vaccine has some logistical advantages, including a two-year shelf life when frozen. It can also be stored for three months at normal refrigerated temperatures, while the Pfizer and Moderna vaccines must be stored in freezing temperatures.

But questions remain about the efficacy of the J&J vaccine for certain populations. While efficacy was consistent among Black, Latino and white vaccine trial participants, the data shows it was only about 42% effective for people over 60 with underlying conditions like diabetes, HIV or high blood pressure.

There is also a dearth of data about efficacy of the J&J vaccine in those 75 years and older. And the vaccine hasn't been tested on children or teens under 18, and so won't yet be approved for that age group.

--Additional reporting by Britain Eakin. Editing by Michael Watanabe.

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