Merck Drops COVID-19 Vaccine Studies After Phase 1 Data Churn Out Inferior Efficacy Results

Merck & Co., Inc. MRK, which was a late entrant to the COVID-19 vaccine fray, has dropped out of the race, and has instead opted to channelize resources on the development of therapeutics candidates for COVID-19, the disease caused by SARS-CoV-2.

What Happened: Merck said Monday it's discontinuing the development of V590 and V591 — two of its COVID-19 vaccine candidates — following the review of findings from the Phase 1 studies of the candidates.

Both V590 and V591, though was generally well tolerated, had an immune response profile that were inferior to those seen following natural infection and those reported for other SARS-CoV-2 vaccines.

Pfizer Inc. PFE-BioNTech SE – ADR BNTX combine and Moderna Inc MRNA received emergency use authorization for their respective coronavirus vaccine candidates in December. These vaccines exhibited efficacy in excess of 90%.

Merck said it will record a charge related to the discontinuation in the fourth quarter, which will be reflected in the GAAP results.

The company said it will now focus on advancing clinical programs and scaling up manufacturing of MK-7110 and MK-4482, the two investigational treatments it is developing to treat COVID-19. Mk-4482, aka molnupiravir, is being developed in collaboration with Ridgeback Bio.

Related Link: The Week Ahead In Biotech: J&J, Lilly to Kickstart Big Pharma Earnings, Amgen FDA Decision and More

What Next: Merck and its collaborators are planning to submit Phase 1 data for V590 and V591 for publication in peer-reviewed journals.

The company reaffirmed its commitment toward COVID-19 research and said it will continue to evaluate the potential of the measles-virus vector and vesicular stomatitis virus vector-based platforms and pursue broader pandemic-response capabilities.

On the two therapeutic candidates, Merck said it expects to release full results from a Phase 3 study of MK-7110 in the first quarter of 2021. In December, the company announced a supply agreement with the U.S. government to advance the manufacturing and initial distribution of MK-7110.

Molnupiravir, the other therapeutic candidate, is currently being evaluated in Phase 2/3 clinical trials in both the hospital and out-patient settings. The primary completion date for the Phase 2/3 studies is May 2021. Initial efficacy data from the study is expected in the first quarter of 2021.

In premarket trading, Merck shares were down 1.1% to $80.02.