Vaccine a potential weapon against skin cancer

Moderna, Keytruda say risk of recurrence or death is reduced by 44% when medical treatments were combined

“Here, we have something that is going to reenergize the field . ... We continue to believe in cancer vaccines, but we need firm clinical proof that they work, and this may be it.”

Keith Knutson, a cancer vaccine researcher at the Mayo Clinic in Jacksonville

Florida is known for its beaches, theme parks and sun — lots and lots of sun.

So it’s no surprise that the Sunshine State’s annual rate of melanoma skin cancer cases is higher than the national rate.

In 2019, there were just over 7,500 new cases in Florida, according to the Centers for Disease Control and Prevention.

Patients got encouraging news recently about a potential new weapon against the deadly illness.

Moderna and Merck announced Dec. 13 that an experimental melanoma vaccine from Moderna, when coupled with Merck’s immunotherapy drug Keytruda, showed promising results in a mid-stage clinical trial.

Melanoma is more dangerous than other types of skin cancer. If it isn’t caught early, it’s more likely to spread to different parts of the body.

Here’s what Floridians should know about the randomized trial.

What happened?

The Phase 2b trial enrolled 157 people with stage 3 or 4 melanoma whose tumors were surgically removed and who were at a high risk of recurrence, according to a news release from the companies.

After undergoing surgery, one group of patients was treated with a combination of Moderna’s vaccine and Keytruda, while another group received only Keytruda.

The companies said the combination reduced the risk of recurrence or death by 44% compared with Keytruda alone. Patients received up to nine doses of the vaccine. It was administered every three weeks.

Moderna and Merck didn’t release the trial data and the results weren’t published in a peer-reviewed journal. But the news release said they will share the information at an upcoming medical conference and with health officials.

Serious drug-related “adverse events” occurred in 14.4% of patients who received the combination and in 10% of those treated only with Keytruda, according to the news release.

How does the vaccine work?

Moderna’s shot is a “personalized” vaccine that uses mRNA technology.

The vaccine is custommade for each patient based on their tumors’ unique mutations. It primes the body’s immune system to target the mutations.

The shot aims to prevent the return of cancer — it isn’t administered to stop people from developing melanoma.

Why are the trial results significant?

The trial offers the first evidence that mRNA technology may be effective against melanoma.

Moderna’s COVID-19 shot also uses mRNA technology, which allows for faster development of vaccines.

The company can make one of its melanoma vaccines within about eight weeks, a Moderna spokesperson said in an email.

The technology “is very exciting,” said Patrick Hwu, president and chief executive officer of Moffitt Cancer

Center in Tampa.

Researchers can test to see if it’s successful against other forms of cancer, said Hwu, a tumor immunologist.

Scientists have been studying cancer vaccines for decades but “none of them have really panned out,” said Keith Knutson, a cancer vaccine researcher at the Mayo Clinic in Jacksonville.

“Here, we have something that is going to reenergize the field,” Knutson said of Moderna’s announcement. “We continue to believe in cancer vaccines, but we need firm clinical proof that they work, and this may be it.”

Federal regulators have yet to approve an mRNA cancer vaccine.

How much will the vaccine cost?

Moderna doesn’t have “an established price” yet, the company spokesperson said in an email.

How bad is melanoma in Florida?

In 2019, Florida had an age-adjusted rate of 24.5 new melanoma cases per 100,000 people, according to federal health officials. By contrast, the national rate was 22.7 cases.

Several smaller states had worse rates than Florida’s, but the Sunshine State’s was higher than those in California, New York and Texas.

Florida reported 656 melanoma deaths in 2019, which was the second-highest in the U.S., according to the Centers for Disease Control and Prevention.

Are there other cancer vaccines?

Yes. The vaccine that protects against human papillomavirus, or HPV, is used to indirectly prevent different cancers. HPV is a common sexually transmitted infection. If it stays in the body long enough, it can cause anal, cervical, oropharynx, penile, vulvar and vaginal cancers, according to the Centers for Disease Control and Prevention.

The Hepatitis B shot is also considered a cancer vaccine. The disease it prevents can cause liver cancer. The sipuleucel-T vaccine can help treat advanced prostate cancer.

Many experimental cancer vaccines are being tested in trials, added Knutson, who is developing a preventative vaccine for breast cancer.

What’s next?

Moderna and Merck plan to start a Phase 3 trial for the melanoma vaccine sometime in 2023, according to the news release.

It will likely take several years before the trial is completed and the U.S. Food and Drug Administration reviews whether to approve the vaccine, Hwu said.

Eventually, patients will be able to enroll in the trial for a chance at receiving the shot.