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From layoffs to political headwinds, Moderna has had a tough few recent years. But last week, employees at the vaccine maker’s Cambridge headquarters got something to celebrate.
Moderna and New Jersey’s Merck announced initial results from a late-stage trial for an experimental melanoma treatment using an mRNA-based cancer vaccine. The companies said for over 1,000 participants who had their melanoma surgically removed, the treatment reduced the likelihood of their cancer returning or spreading.
The news, which reportedly even surprised some of Moderna’s top executives, sent the company’s stock price soaring. In a day, the narrative around Moderna seemed to change.
I wanted to hear more about the treatment at the core of this breakthrough. So I got two doctors with expertise on the subject, Patrick Ott and Ryan Sullivan, to fill me in.
Ott is an oncologist at Dana Farber Cancer Institute and the clinical director of the Melanoma Disease Center. He published a pioneering 2017 study on melanoma vaccines in the journal Nature. Meanwhile, Sullivan directs the cutaneous medical oncology program at Mass General Brigham Cancer Institute. He tested these drugs on his patients in all three phases of the clinical trial.
What does the announcement mean for this area of cancer research?
Scientists have been looking into cancer vaccines for about 50 years, said Ott.
He called these early results “remarkable news.” His previous study suggested a treatment like this could work, but a larger study was needed with more participants. This was the research he’d been waiting for.
“ There was obviously a lot of excitement in the field — or a lot of, let’s say, nervousness — because this study’s considered a bellwether study,” Ott said.
The full results of the trial haven’t been released, and there are still some skeptics. (Moderna said it plans to present the data at an upcoming international medical meeting.) If it lives up to the hype, Ott said it could lead to a whole new frontier of research.
“The melanoma study is the first out of the gates,” Ott told me, “but [Moderna and Merck] actually have more than 10 additional studies in other cancers.” They include lung and bladder cancer.
Sullivan shared in the excitement: “that it might lead to a breakthrough for patients with cancer is amazing.”
“ If this leads to a reinvestment and reinvigoration of modern cancer vaccine development, that can help countless patients in different scenarios that we can’t even think of right now,” Sullivan said.
So, how does the therapy work?
“Cancer is a disease of gene mutations,” said Sullivan. Those mutations make a cancer cell produce special proteins, called “neoantigens.”
The vaccine uses mRNA to train the body’s immune system to identify the neoantigens, “recognize them as foreign and a threat, and get rid of them,” said Sullivan.
The researchers combined the vaccine, called intismeran, with a drug that boosts immune response, Keytruda. The companies’ announcement said the combo produced better results than Keytruda alone.
One special thing about this neoantigen therapy: “ You have to make the vaccine fresh for every patient,” said Ott. Intismeran is completely personalized. It trains a patient’s immune system to attack their particular cancer.
“ If you have an off-the-shelf vaccine, that would be ideal,” said Ott. A vaccine that would target many cancers could help more patients. But, he said, “it probably is not as effective as a personalized vaccine.”
What’s the connection between this cancer treatment and the COVID-19 vaccine?
Moderna is most famous for its mRNA-based COVID vaccine. But before it was adapted for COVID, researchers were originally developing the technology with an eye on cancer.
Sullivan described the past 15 to 20 years of research in the field of cancer vaccines as a rollercoaster ride — except scientists have been at the “bottom part of the rollercoaster and looking up and trying to see if we can get momentum.”
COVID provided the boost needed to get over the hump. Ott said the pandemic forced Moderna to double down on mRNA vaccine research to get the COVID vaccine on the market quickly. He also said the pandemic showed that the industry has the manufacturing capacity to produce mRNA vaccines on a large scale. Compared to some other cancer treatments, a vaccine is “relatively straightforward” to produce, said Ott. That could mean even something as seemingly expensive as a personalized vaccine might be more affordable than certain other drugs.
If the new treatment gets FDA approval, Ott said he would “absolutely” prescribe intismeran to his patients.
“I’m biased,” said Sullivan. “I’ve been treating patients with this for several years now, and I do find that it’s safe. And the fact that it’s been shown to be effective? It’s a no-brainer.”
This article was originally published on WBUR.org.
