Moderna's stock surged significantly in premarket trading following positive Phase 3 trial results for their personalized cancer vaccine. This experimental treatment, developed with Merck & Co., targets melanoma and showed a reduced risk of recurrence. The vaccine, called intismeran autogene, was tested in combination with Merck's immunotherapy drug Keytruda. This combination improved recurrence-free survival compared to Keytruda alone. It also met a secondary goal by decreasing the risk of cancer spreading. This marks the first successful late-stage trial for a personalized cancer vaccine from any company. Experts believe this could establish a new standard of care for adjuvant melanoma treatment. While exact efficacy figures were not released, further details are forthcoming. Regulatory approval could potentially occur as early as 2027. The trial results have also boosted Merck's stock price.