Moderna Share Soars 177%, Merck Stock Price Jumps 12% After Melanoma Vaccine Trial Success

New Delhi, Aug 20: Shares of Moderna (MRNA) and Merck (MRK) surged on Wednesday after their experimental personalised cancer vaccine showed positive results in its first-ever late-stage trial, marking a significant step toward a possible approval filing. Moderna’s stock closed at $174.38, up $111.42, or 176.97 per cent, on volume of 1.99 crore shares, with the stock swinging within a 52-week range of $22.28 to $85.60 before Wednesday’s move blew past that band entirely. Merck’s stock ended the session at $152.20, up $17.03, or 12.60 per cent, on volume of 32.78 lakh shares, also moving beyond its prior 52-week range of $77.58 to $137.98. The scale of the two moves reflected the companies’ vastly different sizes heading into the session, with Merck’s market capitalisation at around $333 billion against Moderna’s roughly $25 billion. 

What The Trial Showed 

The mRNA-based shot, used in combination with Merck’s immunotherapy Keytruda, met key goals in a Phase 3 trial involving more than 1,100 patients with higher-risk or advanced melanoma whose detectable cancer had been completely removed through surgery. The combination regimen significantly extended the time patients lived without their melanoma returning, compared with Keytruda alone, and also reduced the risk of the cancer spreading to distant parts of the body. The results build on positive Phase 2 data on the same regimen presented earlier this year. The study will continue to track other outcomes, including overall survival benefit, with the companies planning to present full data at an upcoming international medical meeting. 

Executive Reactions 

Moderna chief executive Stephane Bancel called it “a big moment for medicine, a big moment for patients” in an interview on CNBC’s Squawk Box. Dr Dean Li, president of Merck Research Laboratories, said the companies would likely begin talking to regulatory agencies about the treatment and its safety profile in the coming months, though a timeline for an approval filing remains unclear. 

Why It Matters for Melanoma Treatment 

Melanoma accounts for only about 1 per cent of skin cancers but causes the large majority of deaths among them, with most recurrences developing within two to three years of initial treatment and surgical removal. Dr Jane Healy, Merck’s head of oncology early development, said melanoma patients are typically left grappling with the weight of their diagnosis, uncomfortable treatments such as surgery, and the ongoing worry of the cancer returning. She described the trial results as showing a “clinically meaningful improvement” over Keytruda, the current standard of care, and noted the therapy was well tolerated, with side effects similar to those seen with other common vaccines. 

A Validation Decades in the Making 

Healy added that the results validate a personalised treatment approach the two companies have been developing for decades, positioning the vaccine-immunotherapy combination as a potential new option in a cancer type where treatment innovation has been closely watched by investors and clinicians alike. 

Market Take 

The scale of Wednesday’s rally, particularly Moderna’s near-tripling in value, underscores how binary clinical trial outcomes can be for biotech and pharmaceutical stocks, especially for smaller companies with a narrower drug pipeline. With both stocks trading well outside their prior 52-week ranges after the announcement, investor focus will now shift to the timeline for regulatory engagement and any further data readouts from the ongoing trial, as well as whether the rally can hold once the initial excitement settles, according to CNBC’s reporting. 

Sources:

• https://www.nasdaq.com/market-activity/stocks/mrk
• https://www.nasdaq.com/market-activity/stocks/mrna