Doctors, scientists, and patient advocates are brimming with hope for the future of cancer vaccines after Moderna and Merck announced this week the successful trial results of a personalized messenger RNA treatment for melanoma.
The full results weren’t released yet, but if they hold up, they would signal a major scientific advancement for patients with the deadliest form of skin cancer and a potential breakthrough in the possibilities for treating other kinds of cancer. Researchers have long sought to harness the body’s immune system in a way that accounts for the specifics of each patient’s tumor, and the new injection does just that: it is custom-made for each person.
“Potentially the most exciting implication from this result is that we might see similar results in other tumor types, some of which are even more common than melanoma,” said Dr. David McDermott, chief of medical oncology at Beth Israel Deaconess Medical Center.
Moderna’s vaccine, which was given alongside drugmaker Merck’s blockbuster immunotherapy Keytruda after the cancer was surgically removed, extended how long patients lived without their cancer returning, as well as how long they lived without their cancer spreading, when compared to Keytruda alone.
The vaccine, called intismeran, was made at Moderna’s Marlborough manufacturing facility, tailored to the genetic sequence of a patient’s individual cancer. In an earlier-stage trial, the therapy reportedly resulted in a 49-percent reduced risk of the cancer returning or spreading.
The latest results came from a Phase 3 trial, the final stage before seeking Food and Drug Administration approval. About 8,510 people are expected to die of melanoma this year in the US, and 112,000 new melanomas will be diagnosed this year, according to the American Cancer Society.
Moderna is testing its personalized vaccine technology, also in partnership with Merck, on a slate of different cancers.
A few Phase 3 trials are targeting non-small cell lung cancers at various stages. Lung cancer of all kinds will cause nearly 125,000 deaths in the US this year, according to the American Cancer Society.
Phase 2 trials are also ongoing for renal cell carcinoma — the most common kind of kidney cancer. Moderna expects to have an interim analysis — or a mid-trial review of how the study is going — for the renal cell cancer vaccine either later this year or early next, said David Berman, Moderna’s chief development officer.
Kidney cancers of all kinds will kill about 15,160 people this year in the US, the American Cancer Society estimates.
Another Phase 2 trial is under way for bladder cancer, which the society estimates will kill 17,870 people in the US this year. The company expects to have results on the bladder cancer trial next year, Berman said.
Moderna is also running a Phase 2 trial for a vaccine that would treat melanoma that has already spread to other parts of the body.
Scientists aren’t the only ones closely monitoring these developments. Cancer patients and caregivers are following the news, waiting for shreds of hope that new treatment options are on the horizon.
Chelsea Kline, executive director of Cancer Connection, a nonprofit cancer support center in Northampton and Springfield, said she is cautiously optimistic that the technology could make a difference for patients suffering from other cancers.
“I lost one of my dearest friends to melanoma, so it’s bittersweet,” Kline said. “If only [the treatment] had come earlier. But if you can prevent someone from losing their person in the future, that’s very exciting.”
While the mere existence of an effective cancer vaccine is reason for jubilation, another potential boon of Moderna’s melanoma therapy candidate is its seemingly limited side effects, Beth Israel’s McDermott said.
The type of drug the vaccine is paired with can cause serious, sometimes permanent issues for a small subset of patients, McDermott said, making it critical that the vaccine doesn’t add even more risk.
Moderna’s work on cancer has been many years in the making, and represents a “back to the future” moment for the company, said Berman.
Though COVID was the disease that made the company a household name, Moderna was originally founded in 2010 to target cancer and other diseases using mRNA, the molecule that carries the genetic instructions needed to make proteins.
The COVID and cancer shots are based on different types of targets — protecting against viruses requires a different part of the immune system than protecting against cancer recurrence — but Moderna found the research and development of each informed the other.
At the outset of the pandemic, the country needed a vaccine, and quickly, to protect people against the rapidly spreading COVID virus. It was a task Moderna was uniquely primed to do, Berman said. The whirlwind production and success of that vaccine and its booster shot successors, in conjunction with a similar product from drugmakers Pfizer and BioNTech, effectively ended the pandemic threat that claimed more than 1 million US lives, scientists agree.
It also made Moderna the target of political backlash, led by noted vaccine and mRNA technology skeptic Robert F. Kennedy Jr., now secretary of the US Department of Health and Human Services. The federal government in 2025 severed a $766 million contract with the firm to develop an mRNA vaccine against bird flu, and Moderna faced unusual hurdles by the US Food and Drug Administration in the approval of its mRNA flu vaccine for older adults.
Moderna tumbled off of its pandemic-era high, which had made some of its founders and top executives billionaires. The company cut its Massachusetts workforce by more than 40 percent, now down to about 2,600 employees.
The biotech returned to its cancer roots, this time armed with the experience of producing vaccines under an extreme time crunch. That’s particularly important when it comes to cancer vaccines, Berman said, since the development and manufacturing of a personalized therapy has to happen within about six weeks from when a patient’s tumor is sampled.
“From the identification of the COVID sequence to actually making the first drug was, I think, 42 days,” said Berman, who joined the company earlier this year. “That speed and turnaround is exactly what’s needed in getting this to the patient before they progress.”
To manufacture the melanoma vaccine therapy, scientists take samples from patients’ tumors, identify their unique genetic mutations, then incorporate that information into making several rounds of injectable treatments at the Marlborough facility, Berman said. The vaccine, when injected, helps train the person’s immune system to recognize cancerous cells to attack.
TD Cowen analyst Tyler Van Buren said Wednesday’s clinical trial results were a “huge deal” for Moderna, which was evident when the company’s share price closed at more than $174 on Wednesday, nearly triple its price at market close Tuesday.
“If these data did not hit, then Moderna would have largely been stuck as a respiratory illness vaccine company,” Van Buren said, “but by having this positive trial readout, it transforms the company into an oncology company as well.”
Marin Wolf can be reached at marin.wolf@globe.com.