Moderna stock doubles after cancer vaccine succeeds in late trials

Moderna (MRNA) shares more than doubled Wednesday after the company and Merck announced that their experimental personalized mRNA cancer treatment significantly reduced the risk of melanoma returning or spreading in a late-stage clinical trial.

Moderna shares were up about 129% at roughly $144 in midmorning trading, while Merck gained nearly 12%. The rally added billions of dollars to the companies’ market values and reflected growing investor confidence that personalized mRNA technology could become a major new approach to cancer treatment.

The Phase 3 INTerpath-001 trial tested intismeran autogene, formerly known as mRNA-4157 or V940, alongside Merck’s Keytruda in patients whose high-risk melanoma had been completely removed through surgery.

The combination met the trial’s primary goal of improving recurrence-free survival and a key secondary goal of improving distant metastasis-free survival compared with Keytruda alone, Merck and Moderna said Wednesday. The improvements were statistically significant and clinically meaningful.

The companies said the result represents the first positive Phase 3 trial for an individualized neoantigen therapy and the first positive late-stage trial of an mRNA-based cancer treatment.

Unlike vaccines designed to prevent an infectious disease, intismeran is a therapeutic treatment created separately for each cancer patient. Doctors analyze mutations found in a patient’s tumor and use that information to produce an individualized mRNA treatment containing instructions for as many as 34 tumor-specific targets, known as neoantigens.

The goal is to train the immune system to recognize those targets and attack cancer cells carrying them. Keytruda, an immunotherapy drug, works alongside the treatment by helping the immune system recognize and fight tumor cells.

The global Phase 3 study enrolled 1,137 patients with completely resected stage IIB through stage IV melanoma. Participants were randomly assigned to receive intismeran and Keytruda or Keytruda alone following surgery.

The companies have not yet released the full Phase 3 data, including the precise reduction in the risk of recurrence or metastasis. Those results are expected to be presented at an upcoming international medical meeting and shared with regulators. The trial will also continue to evaluate overall survival.

Still, earlier results provided a strong signal of the treatment’s potential.

Five-year data from a smaller Phase 2b trial released earlier this year showed that intismeran combined with Keytruda reduced the risk of melanoma recurrence or death by 49% compared with Keytruda alone. The combination also reduced the risk of distant metastasis or death by 59%.

The Phase 3 success now provides much stronger evidence from a far larger patient population.

For Moderna, the result also carries major financial significance. The company became one of the world’s most prominent biotechnology firms during the COVID-19 pandemic, but its shares later fell sharply as demand for COVID vaccines declined. The success of its cancer program gives investors fresh evidence that Moderna’s mRNA platform could produce major products beyond infectious-disease vaccines.

Merck also stands to benefit. Keytruda is already one of the world’s leading cancer medicines, and pairing it with a personalized treatment that further lowers the risk of recurrence could strengthen the drugmaker’s oncology business.

The companies are studying intismeran across a much wider range of cancers. Their development program now includes nine Phase 2 and Phase 3 trials involving melanoma, non-small cell lung cancer, bladder cancer and kidney cancer, among other settings.

No new safety concerns were identified in the Phase 3 melanoma trial, according to Merck and Moderna. The companies said the safety profiles were consistent with earlier studies of the combination.

The treatment remains experimental and has not yet been approved for use. Merck and Moderna said they plan to discuss the Phase 3 results with regulatory authorities as they prepare potential approval filings.