Merck Stock Slides After Reaching New High Amid Valuation Concerns

Merck stock declined by 1.1% in pre-market trading today after surging to a new 52-week high of $153.50 yesterday due to promising results from its Phase 3 trial with partner Moderna.

The company's mRNA-based cancer therapy, intismeran autogene, combined with Merck's immunotherapy Keytruda, met both primary and key secondary endpoints in the INTerpath-001 trial involving over 1,100 high-risk melanoma patients.

While this marks a significant breakthrough for Merck's oncology franchise, analysts are mixed on the stock's valuation. Morgan Stanley upgraded MRK to Overweight from Equal Weight, but Citi expressed concerns about the efficacy data.