MRNA Stock Plunges 18% After Leaked Melanoma Vaccine Data Misses High Hopes

Moderna and Merck reported that their mRNA cancer vaccine, intismeran, reduced death or recurrence risk by 42% in a late-stage melanoma trial. The vaccine, combined with Merck's Keytruda, showed improved recurrence-free and metastasis-free survival rates compared to Keytruda alone. The companies plan to seek regulatory approval and presented the data at a medical conference.

Moderna and Merck's mRNA cancer vaccine, intismeran, reduced melanoma recurrence risk by 42% in a study. The vaccine, tailored to each patient's tumor, was tested on 1,100+ high-risk melanoma patients. Moderna shares dropped 18% after results were released, despite being 200% higher since August.

Moderna (MRNA) fell 17.57% to $202.63 after reports of a data leak on its melanoma vaccine. The S&P 500 and Nasdaq also declined. Investors await full Phase 3 data on Oct. 24. Trading volume was 148% above average. BioNTech (BNTX) and Novavax (NVAX) also dropped.

Merck (MRK) and Moderna (MRNA) shares fell after leaked data from their cancer vaccine trial showed a 0.58 hazard ratio, below investor expectations. The combo therapy reduced recurrence or death risk by 42%. Analysts question commercial potential, though Merck claims efficacy. Both stocks dropped, with Moderna down 21%.

Moderna (MRNA) stock dropped 18% after leaked late-stage trial data for its melanoma vaccine showed a 42% risk reduction, lower than an earlier study's 49%. The stock fell to $202.63, wiping $17B off its market value. Partner Merck also saw losses. Full results are due at a cancer conference on Saturday.

Moderna (MRNA) shares dropped nearly 20% after leaked data on its melanoma vaccine, developed with Merck (MRK), showed a 42% reduction in recurrence or death risk. The data was set to be released at a conference. Analysts found the results encouraging, but the market reaction may reflect high expectations. Merck shares fell 2%.