Merck Stock Soars Near Record Highs on Cancer Vaccine Breakthrough

Merck & Co., Inc.'s (US58933Y1055) stock has reached near-record highs, trading around $152.85 in late August 2026 as investors react positively to strong oncology data and resilient fundamentals.

The company's shares have been on a tear, gaining over 12 percent in the prior week alone, and are now just shy of their 52-week high of $154.49.

The recent move is largely attributed to Merck's success in a personalized cancer vaccine program for high-risk melanoma patients, where the therapy is combined with the company's immune checkpoint inhibitor Keytruda.

Merck and its partner reported Phase 3 data showing improved recurrence-free survival and distant metastasis-free survival when the customized mRNA-based treatment was added to Keytruda, reinforcing confidence in Merck's oncology growth engine.