Moderna and Merck’s Personalized mRNA Cancer Vaccine Succeeds in Phase 3 Trial for Melanoma

A Historic Result

Moderna and Merck announced Wednesday that their personalized mRNA cancer vaccine passed its Phase 3 clinical trial for melanoma. The vaccine, called intismeran, was combined with Merck’s immunotherapy drug Keytruda. Together, the two treatments outperformed Keytruda alone. The trial met both its primary goal and a key secondary goal. It is the first Phase 3 success ever recorded for a personalized neoantigen therapy. It is also the first time an mRNA-based cancer treatment has succeeded at this stage of testing.
Moderna CEO Stephane Bancel called it as big a moment for humanity as November 16, 2020 — the day his company announced that its COVID-19 vaccine worked. He told CNN: “This is a new chapter in cancer care.”

What the Trial Found

The INTerpath-001 trial enrolled 1,137 patients with high-risk melanoma that had been surgically removed. Patients were split into two groups. One group received intismeran plus Keytruda. The other received Keytruda alone. The combination group lived significantly longer without their cancer returning. The combination group also had a lower rate of the cancer spreading to distant parts of the body.
No new safety concerns appeared during the trial. The side effect profile was consistent with what had been seen in earlier studies.

How the Vaccine Works

Most cancer drugs treat all patients the same way. This vaccine is different. Doctors analyze the specific genetic mutations found in each patient’s own tumor. The vaccine is then built to match those mutations. Each dose is unique to the person receiving it.
The goal is to teach the patient’s immune system to recognize and attack those specific cancer markers. Keytruda works alongside the vaccine by helping the immune system mount a stronger attack. Together, the two treatments give the body a more targeted and more powerful way to fight the disease.

What Happens Next

Moderna said the company and Merck plan to file for regulatory approval within months. Dr. Dean Li, president of Merck Research Laboratories, said the companies will begin conversations with the FDA and other global health regulators about the path forward. The full trial data will be presented at an upcoming medical conference. The Phase 3 study is continuing to track overall survival, which was not part of Wednesday’s interim readout.
Both companies are also running separate trials of intismeran against other cancer types. Current studies include non-small cell lung cancer, bladder cancer, and renal cell carcinoma.

The Market Reaction

Moderna’s stock jumped roughly 17 percent on Wednesday after the announcement. Merck’s stock rose more than 12 percent. Moderna’s market cap sat near $25 billion before the news. Merck’s stood near $333 billion. Analysts at Leerink Partners had previously called the Phase 3 result a make-or-break event for Moderna’s stock price and its long-term valuation.

Source: CNN, CNBC, STAT News, Fierce Biotech, AJMC, Chemical & Engineering News