Merck & Co. will discontinue two experimental COVID-19 vaccines and divert resources to develop related treatments, according to Bloomberg. The company said its early trial data failed to generate immune responses comparable to natural infection or existing vaccines.

  • Merck, with a long history of successfully developing vaccines, has been using a more traditional approach of focusing on shots based on weakened viruses.
  • Merck finalized recruiting the first participants for early-stage safety studies near the end of 2020, with interim results from trials coming this month.
  • The company’s vice president Nick Kartsonis termed the trial results “disappointing, and a bit of a surprise.” 
  • The failure of Merck’s candidates will lock the company out of the market, likely to be dominated by two U.S. rivals, Pfizer and Moderna.
  • Neither of Merck’s candidates was among the six primary vaccines in the U.S. government’s Operation Warp Speed portfolio.
  • Merck is expected to record a rise in costs relating to halting programs in the fourth quarter of 2020 in the wake of discontinued vaccine developments. 
  • Merck’s executives, nonetheless, expect U.S regulators to grant emergency-use authorization for its COVID-19 treatment drug candidate, MK-7110, which is complex and difficult to make at a mass scale. 
  • The company is also working on a pill, known as molnupiravir, for COVID-19 treatments at earlier stages of the disease. 

Merck & Co. stock is currently declining. MRK: NYSE is down 1.33% on premarket.