Merck announced that the company is discontinuing development of its SARS-CoV-2/COVID-19 vaccine candidates, V590 and V591, and plans to focus its SARS-CoV-2/COVID-19 research strategy and production capabilities on advancing two therapeutic candidates, MK-4482 and MK-7110. This decision follows Merck’s review of findings from Phase 1 clinical studies for the vaccines. In these studies, both 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 continues to advance clinical programs and to scale-up manufacturing for two investigational medicines, MK-7110 and MK-4482, or molnupiravir, which is being developed in collaboration with Ridgeback Bio. Due to the discontinuation, the company will record a charge in the fourth quarter of 2020. The charge will be included in Merck’s generally accepted accounting principles results, but will not impact non-GAAP results, the company said. Merck and its collaborators plan to submit the results of the Phase 1 studies for V590 and V591 for publication in a peer-reviewed journal. In addition to advancing the development and production of MK-7110 and MK-4482, Merck will continue to conduct SARS-CoV-2/COVID-19 research. Merck will also continue to evaluate the potential of the measles-virus vector and vesicular stomatitis virus vector-based platforms and pursue broader pandemic-response capabilities. The COVID-19 pandemic underscores the need for our company and our industry to continue to invest in research to address threats to health security. “We are grateful to our collaborators who worked with us on these vaccine candidates and to the volunteers in the trials. We are resolute in our commitment to contribute to the global effort to relieve the burden of this pandemic on patients, health care systems and communities,” said Dr. Dean Y. Li, president, Merck Research Laboratories.