Moderna and Merck melanoma vaccine succeeds in major Phase 3 cancer trial

An experimental personalised mRNA cancer vaccine developed by Moderna and Merck has successfully met its main goals in a major Phase 3 trial involving people with high-risk melanoma.

The treatment, known as intismeran autogene, or V940, was given alongside Merck’s immunotherapy drug Keytruda to patients whose melanoma had been completely removed through surgery.

Interim results announced on Wednesday showed the combination produced a statistically significant and clinically meaningful improvement in recurrence-free survival compared with Keytruda alone.

It also significantly improved distant metastasis-free survival – meaning patients receiving the combination were less likely to experience their cancer spreading to another part of the body.

The INTerpath-001 trial involved 1,137 patients with completely resected stage IIB, IIC, III or IV cutaneous melanoma who had not previously received systemic treatment for their cancer.

Patients were randomly assigned to receive Keytruda either alone or alongside the personalised mRNA treatment for approximately one year. Unlike a traditional vaccine designed to prevent an infectious disease, intismeran is individually designed for each patient’s cancer.

The treatment uses genetic sequencing of a patient’s tumour to identify mutations unique to their cancer. A personalised mRNA therapy is then created to help train the patient’s immune system to recognise specific tumour markers and attack cancer cells.

The results represent the first positive Phase 3 trial for an individualised neoantigen therapy and the first positive Phase 3 trial of an mRNA-based cancer therapy.

No new safety concerns were identified during the interim analysis.

The companies have not yet released detailed figures showing the size of the reduction in recurrence and metastasis in the Phase 3 study. Full results are expected to be presented at a forthcoming medical meeting and submitted to regulatory authorities.

However, the findings build on encouraging longer-term results from an earlier Phase 2b study.

Five-year follow-up data published earlier this year showed that patients receiving intismeran alongside Keytruda experienced a 49% reduction in the risk of cancer recurrence or death compared with Keytruda alone.

The same earlier study found a 59% reduction in the risk of distant metastasis or death.

The Phase 3 study will now continue to assess other important outcomes, including whether the treatment improves overall survival.

The results mark a significant milestone in efforts to use mRNA technology beyond infectious disease vaccines and towards personalised treatments capable of directing the immune system against an individual’s cancer.

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