Merck (MRK) Stock After Hours on Dec. 19, 2025: Trump Drug-Pricing Deal, FDA Fast-Track Vouchers, and What to Watch Before Markets Reopen
Merck shares closed at $101.09 Friday, up 0.4%, then dipped slightly after hours as investors reacted to new U.S. drug-pricing agreements and FDA acceleration for two pipeline drugs. Trading volume surged to 43.6 million shares after the Trump administration and major pharma firms, including Merck, finalized deals to cut drug prices and grant tariff relief.