A vaccine launched by Merck and Moderna was found to reduce the chances of skin cancer when used with the drug Keytruda, according to a new study released Monday.

The new results found that 79 percent of participants who received the vaccine and Keytruda stayed cancer-free for 18 months compared to just 62 percent of people who only received Merck’s Keytruda. The companies also said that the results of Phase Two showed mild side effects with the vaccine, like fatigue, injection site pain or chills.

“Today’s results provide further encouragement for the potential of mRNA as an individualized neoantigen therapy to positively impact patients with high-risk resected melanoma,” Kyle Holen, Moderna’s Senior Vice President and Head of Development, Therapeutics and Oncology, said in a statement.

“The profound observed reduction in the risk of recurrence-free survival suggests this combination may be a novel means of potentially extending the lives of patients with high-risk melanoma,” Holen said. “We look forward to starting the Phase 3 melanoma trial soon and expanding testing to lung cancer and beyond.”

This trial used 157 patients who had high risk stage 4 or 5 melanoma and who were disease-free after having the melanoma removed. The participants received the two drugs after the melanoma was removed and then received Keytruda every three weeks until they received 18 treatments.

The study will be starting its phase 3 of the trial in 2023, which will include patients with adjuvant melanoma to expand to additional tumor types. The companies completed its phase 3 study in December, finding it reduced the risk of recurrence or death by 44 percent among the participants. Phase 1 marked the first time that an mRNA vaccine created an immune response in a patient who was taking another drug.