Moderna Present Positive data for mRNA Cancer Vaccine, Safety Concerns Remain: Experts

An experimental mRNA vaccine significantly reduced the risk of skin cancer recurrence and death in patients when used in combination with the immunotherapy Keytruda,  Moderna and Merck announced this month.

Skin cancer is the most commonly diagnosed cancer in the U.S., with melanoma being the most serious type.

The randomized trial included 157 patients with stage III or IV melanoma who had previously undergone surgery, according to data provided by the drug manufacturers.

One group of patients was given nine doses of the experimental mRNA vaccine (mRNA-4157/V940) made by Moderna and the immunotherapy drug Keytruda, made by Merck, every three weeks for about a year. Another group was only given Keytruda.

The mRNA cancer vaccine was used to stimulate an immune response by generating specific T cell responses based on the unique characteristics of a patient’s tumor. Keytruda is a monoclonal antibody that increases the immune system’s ability to detect and fight tumor cells.

They found that the combination of Keytruda and the mRNA vaccine reduced the risk of cancer recurrence or death by 44 percent compared to using Keytruda alone.

“Today’s results are highly encouraging for the field of cancer treatment,” Stéphane Bancel, chief executive officer for Moderna, said in a press release. “mRNA has been transformative for COVID-19, and now, for the first time ever, we have demonstrated the potential for mRNA to have an impact on outcomes in a randomized clinical trial in melanoma.”

The preliminary results of the phase 2b trial were shared by the companies in the press release. They have not yet been published or peer-reviewed.

Merck and Moderna said a phase 3 study in melanoma patients will start next year, and the companies will look at additional tumor types.

Sanjay Philip Oommen, M.D., hematologist oncologist at Texas Oncology and member of the medical staff at Texas Health Harris Methodist Hospital Fort Worth, told The Epoch Times that immunotherapy has been the hallmark of treatment of advanced melanoma to improve survival and prevent recurrence.

Having a vaccine that utilizes mRNA technology is “a tremendous leap forward” for treatment of individuals who have stage III and IV melanoma, he added.

mRNA-based cancer treatment vaccines have been tested in small clinical trials for many years, but previous attempts have been limited by drug instability, poor ability to stimulate an immune response, and inefficient delivery of genetic material into the body.

Moderna’s mRNA cancer vaccine was used in combination with Keytruda because larger or more advanced tumors proved hard to eradicate using only a vaccine, explained Eric Maroyka, PharmD, BCPS, senior director, Center on Pharmacy Practice Advancement at the American Society of Health-System Pharmacists (ASHP).

According to Maroyka, challenges for finding cancer vaccines that work include:

• Cancer cells suppress the immune system.
• Cancer starts from normal, healthy cells and may be hard for the immune system to detect.
• People with cancer have a weakened immune response.

“Especially the elderly,” he emphasized.

This means they may not be able to produce a strong immune response after receiving a vaccine.

The cancer vaccine technology that Moderna tested was foundational to developing their mRNA COVID vaccine.

A substantial number of trial participants experienced side effects associated with treatment.

During the trial, serious treatment-related adverse events occurred in 14.4 percent of patients receiving both the mRNA vaccine and immunotherapy. Adverse events affected 10 percent of those who received Keytruda alone, the companies said.

“Cancer treatment vaccines can cause side effects, which affect people in different ways,” said Maroyka.

These side effects may depend on how healthy a person is before treatment, the type of cancer, how advanced it is, and the type and dose of treatment vaccine received.

Robert Malone, M.D., cautioned that there could be misleading shorter-term data. Dr. Malone is the original inventor of mRNA vaccination as a technology, DNA vaccination, and multiple non-viral DNA and RNA/mRNA platform delivery technologies.

“You really have to watch for longer-term outcomes,” he said, particularly when the vaccines have nanoparticles that possess some “intrinsic toxicity.”

“Which is the case here,” Malone said.

Regarding the cancer vaccine arena, Malone said he’s watched this “cycle around eight or 10 times now with various supposed breakthroughs” that are often stepping stones but not necessarily the breakthroughs that they’re touted to be.

“So I would recommend taking a tone that is cautiously hopeful,” he advised. “Maintain an optimistic, perhaps at times, overly optimistic stance, but avoid buying into marketing hype that Pharma has a tendency towards.”

In general, the platform technology seems to progress, but there are multiple obstacles to robust, long-term, successful outcomes.

“We have a general, gradual, stepwise improvement in cancer vaccine technology,” said Malone. “But I haven’t seen evidence of an overwhelming breakthrough in melanoma, pancreatic cancer, or glioblastoma multiforme—those are all really challenging targets.”

George Citroner is a health reporter for The Epoch Times.