Moderna and Merck announced positive results from a late-stage trial for their personalized mRNA cancer vaccine, intismeran, in combination with Keytruda, for patients with high-risk melanoma. This marks the first positive Phase 3 trial for an mRNA cancer vaccine, demonstrating its ability to reduce the risk of recurrence and cancer spread.
Following the announcement, Moderna's shares surged by as much as 177%, adding nearly $45 billion to its market value and bringing its stock price to levels not seen since 2024. Merck's shares also climbed over 12%. Analysts like Trung Huynh of RBC Capital Markets and Tyler Van Buren of TD Cowen called the results a "major win" and a "landmark moment," with some projecting intismeran could achieve up to $5.4 billion in peak annual sales for melanoma alone.
This success has restored Wall Street's faith in Moderna, which had seen its stock price plummet after initial COVID-19 vaccine sales slowed. The trial success is seen as a significant validation of mRNA technology beyond infectious diseases. If approved, the vaccine could benefit thousands of melanoma patients as early as next year. However, some analysts, including Cory Kasimov of Evercore ISI and Daina Graybosch of Leerink Partners, cautioned that the market's euphoric response might have set overly optimistic expectations for the vaccine's sales potential and its applicability to other cancer types, noting that melanoma is "uniquely suited to a vaccine."
