Merck and Moderna have reported that their experimental messenger RNA (mRNA) vaccine for melanoma, when used alongside the immunotherapy drug Keytruda (pembrolizumab), lowered the risk of the cancer returning or causing death by 44 percent in a Phase 2 clinical trial. The vaccine, known as mRNA-4157/V940, is designed to train the immune system to recognize and attack mutations unique to a patient’s tumor. Based on these results, the companies plan to launch a larger Phase 3 study to confirm the findings and seek regulatory approval.

Key takeaways

  • The experimental vaccine is personalized for each patient, targeting up to 34 specific neoantigens from their tumor.
  • In the Phase 2 trial, the combination of vaccine plus Keytruda reduced the risk of recurrence or death by 44% compared to Keytruda alone.
  • The treatment is being developed for high-risk melanoma patients after surgical removal of the tumor.
  • Merck and Moderna say they will initiate a Phase 3 trial in 2023 to further evaluate the vaccine.
  • If successful, this could become one of the first personalized mRNA cancer vaccines to reach the market.

How the personalized melanoma vaccine works

The vaccine is built on Moderna’s mRNA platform, the same technology used in its COVID-19 shot. But instead of targeting a virus, it is tailored to each individual’s cancer. After a patient’s tumor is surgically removed, scientists sequence its DNA to identify unique mutations called neoantigens. The vaccine contains mRNA instructions for up to 34 of these neoantigens. Once injected, the body’s cells produce the corresponding proteins, prompting the immune system to generate T cells that can hunt down any remaining melanoma cells carrying those mutations.

Keytruda, a checkpoint inhibitor, is given alongside the vaccine. It works by taking the brakes off T cells, allowing them to attack the tumor more aggressively. The combination aims to both stimulate a targeted immune response and remove the cancer’s ability to hide from the immune system.

Clinical trial results

The Phase 2 trial enrolled about 150 patients with high-risk melanoma whose tumors had been surgically removed. Participants were randomly assigned to receive either the vaccine plus Keytruda or Keytruda alone. After a median follow-up of about two years, the vaccine combination showed a 44% reduction in the risk of recurrence or death. The companies presented the data at the American Association for Cancer Research annual meeting and published it in the journal The Lancet.

Side effects were similar between the two groups, with fatigue, injection-site reactions, and fever being the most common. No new safety signals were reported. The companies emphasized that the results are preliminary and need confirmation in a larger population.

What this means for patients

Melanoma is a serious form of skin cancer that can spread to other parts of the body. For patients with high-risk disease, even after surgery, the chance of recurrence remains significant. Current treatments include immunotherapy drugs like Keytruda, but not all patients respond. A personalized vaccine could offer a new option that targets the specific genetic drivers of each person’s cancer.

If the Phase 3 trial confirms the benefit, the vaccine could become part of standard care for certain melanoma patients. However, the personalized nature of the vaccine means it is complex and costly to produce, which may limit early access. The companies have not yet disclosed pricing plans.

Future outlook and next steps

Merck and Moderna plan to start a Phase 3 trial in 2023 that will enroll a larger number of patients globally. They are also exploring the vaccine in other cancer types, including non-small cell lung cancer. The success of the melanoma trial has boosted confidence that mRNA technology can be applied beyond infectious diseases to create personalized cancer treatments.

Regulatory agencies such as the FDA have granted breakthrough therapy designation to the vaccine, which can speed up the development and review process. If the Phase 3 data are positive, the companies could apply for approval within the next few years.

Frequently Asked Questions

What is the melanoma vaccine from Merck and Moderna?

It is an experimental personalized mRNA vaccine called mRNA-4157/V940. It is designed to be used together with the immunotherapy drug Keytruda in patients with high-risk melanoma that has been surgically removed. The vaccine is tailored to each patient’s unique tumor mutations.

How effective is the vaccine in the trial?

In the Phase 2 trial, the combination of the vaccine and Keytruda reduced the risk of melanoma recurrence or death by 44% compared to Keytruda alone. The results were presented at a medical conference and published in a peer-reviewed journal. A larger Phase 3 trial is needed to confirm these findings.

When will the melanoma vaccine be available to patients?

The vaccine is not yet approved. The companies plan to start a Phase 3 trial in 2023. If that trial shows positive results and regulatory approval is granted, the vaccine could become available in the next few years. It is currently only available through clinical trials.

This is an original report by Vital Signs Today, informed by reporting from Google News. Read the original source.

This article is for information only and is not medical advice. See our Medical Disclaimer.