Moderna Shares Plunge After Melanoma Vaccine Data Leak
Moderna shares suffered their largest intraday drop ever following a leak of partial data for a personalized melanoma vaccine developed with Merck.
Shares of Moderna plunged as much as 25% on Thursday after partial data leaked regarding intismeran autogene, a personalized melanoma vaccine developed in partnership with Merck. The sell-off marked the largest intraday drop in the company's history, while Merck shares declined by approximately 1%.
Full phase 3 trial results released later that day indicated the vaccine, used alongside Merck's immunotherapy Keytruda, reduced the risk of cancer recurrence or death by 42% and the risk of distant metastases or death by 38% compared to Keytruda alone. Despite these figures appearing positive relative to Wall Street expectations, the initial leak triggered significant investor volatility.
The companies intend to present detailed findings this weekend at the European Society for Medical Oncology conference in Madrid. A current challenge for the treatment is its personalized nature, which requires a six-week manufacturing process. Merck CEO Robert Davi stated the company believes it can shorten this timeline.
