Moderna's stock experienced a sharp decline on Thursday, falling as much as 25% before recovering to trade down 16%, despite the release of positive clinical trial data for its personalized cancer vaccine. The sell-off was triggered by a breach of the data embargo, which led to the early circulation of trial results and heightened market volatility.
The vaccine, known as intismeran autogene, is being developed in partnership with Merck and is designed to be used alongside Merck's immunotherapy drug Keytruda for the treatment of high-risk melanoma. The trial results showed that the combination reduced the risk of cancer recurrence or death by 42% compared with Keytruda alone, with a hazard ratio of 0.58 for recurrence-free survival.
Specifically, approximately 82% of patients who received the vaccine alongside Keytruda were alive without their melanoma returning after two years, compared with 70% of those treated with Keytruda alone. Additionally, the combination reduced the risk of cancer spreading to distant organs or death by 38%.
Despite these clinically meaningful results, the market reaction suggested that investors had anticipated even stronger efficacy data. Several analysts had set expectations for the trial outcomes before the data was released. For instance, UBS analyst Michael Yee had indicated that a hazard ratio of 0.65 could support a 10% to 20% rally in Moderna shares, while Leerink Partners analyst Daina Graybosch had identified a figure below 0.60 as a potentially transformative outcome.
The reported hazard ratio of 0.58 was better than these thresholds, yet the stock still declined sharply. William Blair analyst Myles Minter described the move as a potential sell-the-news reaction, noting that Moderna shares had risen more than 500% this year despite Thursday's fall. UBS analysts also described the results as a strong dataset, suggesting that the stock reaction reflected high expectations rather than disappointing efficacy.
However, some analysts pointed out that the reduction in the risk of cancer spreading to distant organs fell short of certain Wall Street projections, according to TD Cowen analyst Tyler Van Buren. This may have contributed to the negative sentiment.
Investors view intismeran autogene as a potential growth driver for Moderna beyond its existing vaccine portfolio, which includes products for COVID-19, influenza, and respiratory syncytial virus. The personalized cancer vaccine is being evaluated across nine trials involving different solid tumors, and positive results could strengthen confidence in upcoming studies targeting kidney and bladder cancers.
One of the challenges for the vaccine is its manufacturing process, which takes approximately six weeks due to its personalized nature. Merck CEO Robert Davis said the company believes it can reduce that timeline in the future, potentially helping the treatment reach more patients.
Merck shares also declined on Thursday, falling around 1.4%, although the move was smaller than Moderna's drop. The sell-off leaves investors weighing the vaccine's clinical promise against the high expectations already reflected in Moderna's share price. While the trial results indicate a meaningful reduction in melanoma recurrence risk, further studies and the treatment's commercial potential will remain important considerations.
This article is for informational purposes only and does not constitute financial advice.
