Positive results from a late-stage trial position Moderna and Merck for regulatory approvals
Category: Health
Moderna’s stock surged by more than 90% on August 19, 2026, nearly doubling its share price after the company announced positive outcomes from a late-stage trial of an experimental cancer vaccine in collaboration with Merck. The results, which are the first successful final-stage findings for any mRNA-based cancer therapy, have positioned the partners to seek regulatory approvals.
Shares of Moderna jumped 93% to approximately $121.90 during trading, marking what is expected to be the stock's best trading session ever. This remarkable increase came after the announcement that their personalized cancer vaccine significantly reduced the recurrence of melanoma, a common form of skin cancer, in a trial involving over 1,100 patients.
The trial, known as the INTerpath-001, evaluated the efficacy of intismeran autogene, also referred to as V940 or mRNA-4157, in combination with Merck’s checkpoint inhibitor, Keytruda (pembrolizumab). According to the companies, patients receiving the combination treatment experienced longer periods without melanoma recurrence, successfully meeting the trial’s primary endpoint of recurrence-free survival (RFS).
In addition to the primary endpoint, the study also achieved a secondary endpoint that measured the duration of time patients lived without metastatic lesions appearing in other parts of their bodies. The improvements in RFS and distant metastasis-free survival observed at the prespecified interim analysis are considered clinically meaningful by both companies.
Merck and Moderna have not yet disclosed specific data from the trial, opting instead to reserve these details for a forthcoming medical meeting. They did, nonetheless, confirm that the safety profiles of the drugs remained consistent with earlier studies and that no new safety signals were identified. Notably, in their June analysis of Phase 2 data, the partners reported no grade 4 or 5 adverse events.
William Blair analysts commented on the development, stating, “We see today’s update as a clear positive for shares and Moderna’s fundamental business.” They upgraded Moderna’s stock rating to Outperform from Market Perform, citing the company’s clear path toward revenue diversification beyond its COVID-19 vaccine, SPIKEVAX.
The Phase 3 INTerpath-001 trial involved 1,137 patients who were randomized in a 2:1 ratio to receive either the combination of the mRNA vaccine and Keytruda or the single-agent Keytruda alone for approximately one year after surgical removal of cutaneous melanoma. The study’s design and implementation represent a notable advancement in the application of mRNA technology for cancer treatment, following the success of mRNA vaccines in combating COVID-19.
According to the American Cancer Society, about 112,000 new cases of melanoma are diagnosed each year in the United States, with an estimated 8,510 deaths anticipated. Melanoma is particularly concerning due to its aggressive nature, and lighter skin color is identified as a major risk factor, with increasing age compounding the risk.
This successful trial marks a milestone for Moderna and Merck and has broader implications for the field of oncology. The companies are currently exploring the vaccine's efficacy in several other types of tumors, including non-small cell lung cancer and bladder cancer. The results from this trial may pave the way for future innovations in cancer treatment, particularly through the use of mRNA technology.
Following the positive results of this trial, Merck and Moderna are preparing to engage in discussions with regulatory authorities about the potential for approval filings based on the newly acquired data. Preliminary discussions had previously taken place in 2024, where the companies sought approval based on Phase 2 data but received discouraging feedback from the FDA. With the latest trial results, they now possess a larger dataset and longer-term follow-up data from the Phase 2 study.
Analysts have speculated that intismeran could generate multi-billion dollar peak sales, making it a key asset for both Merck and Moderna. The potential for high sales is particularly pressing as both companies face challenges, including the anticipated loss of exclusivity on Keytruda and a decline in COVID-19 vaccine sales.
David Berman, chief development officer at Moderna, emphasized the importance of this trial in relation to other cancer types, stating, “Positive results from the INTerpath-001 study in adjuvant melanoma add positive read-through for the studies of intismeran in other cancer types.” The next anticipated data release is expected from the Phase 2 study in adjuvant renal cell carcinoma, with results possibly available by the end of the year.
As the companies move forward, the success of the INTerpath-001 trial validates the mRNA cancer approach and opens up a wealth of opportunities across various oncology indications. Investors and healthcare professionals alike are watching closely as the regulatory process progresses, potentially heralding a new era in cancer treatment.