PREVYMIS™ (Letermovir), Merck's CMV Prophylaxis Medicine

Improved synthesis of Prevymis™, a prescription medicine that helps prevent cytomegalovirus (CMV) infection and disease in adults who have received bone marrow transplants. This antiviral drug uses an improved chemical catalyst, increases the overall yield by 60%, reduces the PMI by 73%, reduces raw material costs by 93%, and reduces water usage by 90%. Merk claims this synthesis will result in the elimination of over 15,000 MT of waste over its lifetime. It should also decrease the product's carbon footprint and water usage by 89% and 90%, respectively. The traditional process had a low overall yield of 10%, with little opportunity to recycle solvents or reagents.