Coverage spread: 2 sources — 1 left · 1 center
Lean ratings via AllSides / Media Bias-Fact-Check. How this works.
Where they agree
- Merck and Moderna’s personalized mRNA vaccine, combined with Keytruda, extended time without melanoma recurrence versus Keytruda alone in a Phase 3 trial.
- The companies have not yet published full peer-reviewed data, planning instead to present it at a future medical meeting and share it with regulators.
- Moderna’s stock surged dramatically in premarket trading while Merck’s rose more modestly, reflecting the companies’ size difference.
- The trial will continue tracking overall survival as a further measure of the treatment’s benefit.
Where they differ
- CNBC gives more trial detail, including patient count (1,100+), the reduction in distant spread, and specific market cap figures for both companies.
- CNBC includes direct commentary from Merck’s Dr. Jane Healy and Dr. Dean Li on how the vaccine works and next regulatory steps, which NBC News omits.
- NBC News reports a higher premarket stock jump for Moderna (up to 106%) versus CNBC’s reported 90%, suggesting the figures moved during premarket trading.
- NBC News frames the news more around the corporate announcement and stock reaction, while CNBC leans further into the science and regulatory timeline.
Merck and Moderna announced Wednesday that their experimental personalized mRNA cancer vaccine, used alongside Merck’s immunotherapy Keytruda, showed positive results in a Phase 3 trial for patients with high-risk melanoma who had already had their tumors surgically removed. The combination significantly delayed cancer recurrence compared with Keytruda alone, and Moderna’s stock jumped as much as 90-106% in premarket trading on the news, with Merck shares rising around 7-8%.
What did the trial actually find?
The Phase 3 study enrolled more than 1,100 patients with higher-risk or advanced melanoma whose visible cancer had been removed by surgery. Patients received the personalized vaccine, called Intismeran, combined with Keytruda, and were compared against patients getting Keytruda alone. The combo met its main goal: it significantly extended the time before melanoma came back, and it also cut the risk of the cancer spreading to distant parts of the body. These results build on earlier Phase 2 data reported by the companies earlier this year. The trial will keep running to see whether the treatment also improves overall survival, a question the current data doesn’t yet answer.
How does the vaccine work?
Unlike a traditional vaccine, Intismeran isn’t a one-size-fits-all shot. It’s built individually for each patient based on the specific mutations found in their own tumor. Dr. Jane Healy, Merck’s head of oncology early development, explained that every tumor carries a unique set of mutations even among patients with the same cancer type, so the vaccine is designed to train the immune system to recognize and attack those particular mutations. Side effects were described as similar to those from routine vaccines people already receive for other conditions.
Why does melanoma matter here?
Melanoma is the deadliest form of skin cancer. It accounts for roughly 1% of skin cancer cases but is responsible for the large majority of skin-cancer deaths. Most recurrences happen within the first two to three years after initial surgery, which is why preventing or delaying recurrence in high-risk patients after surgery is a major treatment goal. Keytruda alone is currently the standard of care for these patients, so a therapy that meaningfully outperforms it would represent a new option.
What are the companies saying?
Moderna CEO Stéphane Bancel called the results a “pivotal moment” for cancer research, saying that turning mRNA technology into a personalized cancer treatment had long been an aspirational idea that is now becoming real. In a separate interview, he called it “a big moment for medicine, a big moment for patients.” Healy described the improvement over Keytruda as “clinically meaningful” and said the findings validate a personalized treatment approach the two companies have spent decades developing.
What happens next?
The companies have not yet published the data in a peer-reviewed journal or released the full dataset publicly. Instead, they plan to present the results at an upcoming international medical meeting and share them with regulators. Dr. Dean Li, president of Merck Research Laboratories, said the companies expect to begin discussions with regulatory agencies about the treatment’s safety within the next few months, though it remains unclear when they might formally file for approval in the United States.
How are the two markets reacting differently?
Both companies’ stocks rose sharply, but the scale of the reaction reflects their very different sizes. Moderna, a much smaller company with a market cap of about $25 billion entering the day, saw its stock jump between roughly 90% and 106% depending on the report. Merck, with a market cap near $333 billion, saw a smaller but still notable gain of 7-8%. The disparity illustrates how much more this single trial result matters to Moderna’s overall business compared with Merck’s broader, more diversified portfolio.
Sources
Featured photo: Fletcher via Wikimedia Commons (CC BY 4.0)