Why is Moderna stock tumbling today?

Moderna (MRNA) shares fell 17.6% on Oct. 22 after Phase 3 trial results for its cancer vaccine were leaked. The drop occurred despite positive results for the vaccine, developed with Merck (MRK). Analysts attributed the decline to a 'sell the news' event, with Bernstein maintaining a $45 price target and Wells Fargo suggesting concerns may be overdone. Merck shares also dropped 1.76%.

Moderna and Merck's personalized cancer vaccine, intismeran, reduced melanoma recurrence by 42% in a Phase 3 trial. The vaccine, combined with Keytruda, trains the immune system to target tumor proteins. The study involved 1,130 patients, with results replicating earlier Phase 2 data. The effect was noted after six months, suggesting the immune system needs time to activate.

Moderna shares dropped 25% after leaked cancer vaccine data, despite positive results. The vaccine, developed with Merck, reduced recurrence or death risk by 42% in melanoma patients. Analysts noted the data was positive but investors had high expectations. Merck shares fell 1%.

Moderna and Merck released early phase 3 trial data for their mRNA-based skin cancer vaccine, showing a 42% reduction in recurrence or death risk compared to a single treatment. The trial involved 1,137 high-risk melanoma patients. Both companies plan to seek regulatory approval. Moderna's stock dropped following the announcement.

Moderna's shares dropped 17.57% on Oct. 22, closing at $202.63. Despite the decline, the stock is up 587.11% year-to-date. ETMarkets ranked Moderna first among U.S.-listed stocks for gains, with a 733.54% increase through Oct. 21. The company and Merck reported positive Phase 3 trial results for a melanoma treatment.

Moderna and Merck shares fell after leaked data on their personalized melanoma vaccine underwhelmed investors. The companies had previously reported promising results in August, leading to a surge in their stock prices. According to the report, the new data did not confirm the initial optimism.