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Morning Briefing

Summaries of health policy coverage from major news organizations

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Tuesday, Jan 26 2021

Full Issue

Merck Halts Work On Both Its Covid Vaccine Candidates

Merck says that neither of its experimental vaccines produced adequate immune responses against the coronavirus in its clinical trial testing. The drugmaker says it will focus its efforts on developing treatments.

Stat: In A Major Setback, Merck To Stop Developing Its Two Covid-19 Vaccines And Focus On Therapies

Merck said Monday it will stop developing both of the current formulations of the Covid-19 vaccines the company was working on, citing inadequate immune responses to the shots. Work will continue on at least one of the vaccines, which is being developed in partnership with the International AIDS Vaccine Initiative (IAVI), to see if using a different route of administration would improve how effective it is. (Herper and Branswell, 1/25)

NPR: Merck Stops Developing Both Of Its COVID-19 Vaccine Candidates

Merck is halting development of its two COVID-19 vaccine candidates, saying that while the drugs seemed to be safe, they didn't generate enough of an immune response to effectively protect people against the coronavirus. Results of Phase 1 clinical studies showed that the two vaccine candidates — known as V590 and V591 — "were generally well tolerated, but the immune responses were inferior to those seen following natural infection and those reported for other SARS-CoV-2/COVID-19 vaccines," Merck said in a statement about its decision. (Chappell, 1/25)

USA Today: Merck Drops Out Of COVID-19 Vaccine Race, Citing 'Inferior' Immune Responses. But That's Proof Safety Systems Are Working, Experts Say

The decision by U.S. pharmaceutical giant Merck to get out of the COVID-19 vaccine research business should have little direct impact on efforts to vaccinate Americans – and it's proof safety protocols are working, experts say. Developing a vaccine is challenging and laden with failures, so Merck’s announcement Monday that it was giving up development of two COVID-19 vaccines after poor results  wasn’t a complete surprise, said Dennis Carroll, who led the pandemic unit at the federal Agency for International Development for nearly 15 years. The real surprise, he said, is the success of the Pfizer and Moderna vaccines already widely distributed across the U.S. (Bacon, 1/25)

How other companies are doing with vaccine development —

FiercePharma: COVID-19 Tracker: Merck Quits The COVID-19 Vaccine Game; Civica Rx Plots $124M Essential Medicines Plant 

Merck & Co. called it quits on both of its COVID-19 vaccine candidates, citing lackluster efficacy data in phase 1. Meanwhile, Moderna is advancing a virus variant-specific booster shot into preclinical studies and a U.S. phase 1 trial. (Kansteiner, Sagonowsky, Liu and Hale, 1/25)

This is part of the Morning Briefing, a summary of health policy coverage from major news organizations. Sign up for an email subscription.
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