Moderna, Merck Cancer Vaccine Shows Promise in Late-Stage Trial, Boosting Stocks

An experimental personalized cancer vaccine, a collaborative effort between Merck and Moderna, has shown encouraging initial results in its inaugural late-stage trial. This development brings the companies a step closer to seeking approval for this innovative treatment option.

The mRNA-based vaccine, administered in conjunction with Merck's immunotherapy Keytruda, successfully met key objectives in the phase three trial involving over 1,100 patients. These patients had higher-risk or advanced melanoma that had been completely surgically removed.

Following the announcement, Merck's shares saw a rise of over 1% in premarket trading, while Moderna's stock experienced a significant surge of more than 10%.

The combination treatment achieved its primary goal by substantially extending the period patients remained free of melanoma recurrence compared to Keytruda used alone. Furthermore, the therapy demonstrated a reduced risk of cancer metastasis to distant parts of the body. These findings build upon positive phase two trial data for the same regimen presented earlier this year.

The phase three study will continue to evaluate additional outcomes, including the overall survival benefits of the treatment. While the drugmakers intend to present the comprehensive data at an upcoming international medical conference, the timeline for submitting approval applications in the U.S. remains uncertain.

Nevertheless, the preliminary data suggests that this combination could represent a new therapeutic avenue for melanoma, a form of skin cancer that, despite accounting for only about 1% of skin cancers, is responsible for the vast majority of related deaths. Most melanoma recurrences typically emerge within the first two to three years post-initial treatment and surgical removal.

Dr. Jane Healy, Merck's head of oncology early development, expressed her enthusiasm, stating that the therapy has delivered a "clinically meaningful improvement" over Keytruda, the current standard of care for melanoma, and has been well-tolerated by patients. She noted that side effects were comparable to those of common vaccines.

She further highlighted that these results validate the personalized treatment approach that Merck and Moderna have been developing for years. She explained that each tumor possesses a unique set of mutations, even within the same cancer type. Merck and Moderna's personalized vaccine is engineered to target these specific tumor mutations for each patient, moving away from a one-size-fits-all strategy. The underlying principle is to train the patient's immune system to identify and eliminate these unique cancer markers, with Keytruda then enhancing the immune system's ability to fight the cancer more effectively.

Dr. Healy believes the results are "very meaningful for patients with this disease and really the potential of what it can mean for other patients for cancer in future trials with this particular new class of therapy."

Analysts had previously indicated that the phase three results were a critical juncture for Moderna's stock valuation. The company's current market value reportedly already factors in the potential success of the personalized cancer vaccine across various cancer types beyond melanoma.

Merck and Moderna are actively investigating the vaccine in ongoing trials for other cancers, including non-small cell lung cancer, bladder cancer, and renal cell carcinoma.