Merck Stock's Ticking Keytruda Time Bomb

1. Keytruda sales surged 72% to $29 billion, accounting for 46% of MRK revenue. 2. U.S. market exclusivity for Keytruda ends in 2028, inviting biosimilar competition. 3. Sales of Keytruda may drop to $15 billion post-patent expiration. 4. MRK stock has declined by 40% over the past year, reflecting investor concerns. 5. Company needs to identify new revenue sources to mitigate declining sales.