Merck Shares Soar on Successful Melanoma Vaccine Trial

Merck's shares surged by 12% to $152.20 on Wednesday after the company's partner, Moderna, announced the success of their melanoma vaccine in a Phase 3 trial.

The INTerpath-001 study showed that patients who received a combination of Keytruda and intismeran autogene, an mRNA-based cancer vaccine, lived longer without their cancer returning than those who received Keytruda alone.

Analysts say this result validates the idea of individualized cancer vaccines and gives Merck a path to growth even after its Keytruda exclusivity period ends in 2028.

The successful trial also positions Merck and Moderna to move forward with intismeran in cutaneous melanoma, potentially generating $2 billion in unadjusted peak revenue.