Merck (MRK) Stock Update: This Week’s News, Key Catalysts, and the Week-Ahead Outlook (Updated Dec. 12, 2025)
Merck & Co., Inc. (NYSE: MRK) ended Friday, December 12, 2025, at $100.30, climbing 1.30% on the day and finishing slightly higher for the week after a choppy stretch driven by vaccine-policy headlines and scrutiny around RSV preventive therapies. StockAnalysis Below is a detailed, Google News/Discover–ready look at what moved Merck stock this week, what the latest company and sector headlines mean for MRK, what analysts are forecasting, and what investors are watching in the week ahead. Merck stock performance this week: A late rebound after early pressure Closing price (Dec. 12): $100.30.MRK’s weekly story was less about a single