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Molnupiravir is a direct-acting oral, broad-spectrum antiviral agent in clinical development as a treatment for COVID-19. Ridgeback has completed Phase 1 and Phase 2 studies. The program has advanced into Phase 3 development as a therapeutic for COVID-19. Administered as an oral capsule, Molnupiravir has also shown activity in animal models of Ebola, Equine Encephalitis (VEEV and EEEV), Influenza (seasonal, pandemic and avian), and Respiratory Syncytial Virus. 

Molnupiravir is being developed under a collaboration agreement with Merck (known as MSD outside the U.S. and Canada).

Development Pipeline

(MK-4482; EIDD-2801)
Phase 3

* Partnered with Merck


Ridgeback would like to acknowledge and thank our collaborators on the molnupiravir (EIDD-2801) development program:

  • Emory University
  • Merck & Co
  • AGILE network