Modena (MRNA.US) plummeted 25% due to data leak: personalized vaccine expectations fell short

According to Woofun AI, Modena (MRNA.US) shares experienced a sharp drop on Thursday, falling 25% in a single day. This sharp fluctuation was not due to a failure in clinical data, but to the unexpected disclosure of some of the key results of the Intismeran autogene vaccine before official announcement, which led to the market digesting the benefits ahead of time and subsequent profit returns.

Despite a single-day sharp decline, the stock's cumulative increase in 2026 was over 530%, indicating the long-term optimism of capital in the field of personalized oncology treatment.

According to data compiled by Woofun AI, the personalized vaccine can reduce the risk of recurrence or death in melanoma patients by 42% and the risk of distant metastasis or death by 38% when used in combination with Merck (MRK.US) immunotherapy Keytruda. Of the patients receiving the combination treatment, 82% did not relapse and survived after 2 years, compared to 70% in the Keytruda group alone.

Despite the impressive data, BMO Capital Markets (BMO.US) analyst Evan Siegman pointed out that the fall in stock prices reflected previous high market expectations rather than the treatment being ineffective; UBS (UBS.US) analysts also believed that the test results were excellent, and the market reaction was mainly due to the fulfillment of expectations. Notably, Merck's stock price fell by only about 1%, but since 2026, the increase has been close to 41%, showing the stability of large pharmaceutical companies in the face of such news.

However, commercialization still faces serious challenges. Lee Dean, president of Merck Research Laboratories, admits that the current tests only target melanoma, and further verification of its efficacy in other tumor types such as lung cancer, bladder cancer, and kidney cancer is needed. The production process is also a bottleneck. Preparation of each dose of the personalized vaccine takes six weeks and is highly dependent on tumor gene sequencing technology. Merck CEO Robert Davis said the company is committed to shortening this waiting time to accelerate patient benefits. The full phase 3 trial results will be presented at the European Society of Medical Oncology conference this weekend, and more comprehensive survival data will be provided at that time.

For the entire industry, the next core test is whether large-scale production of personalized medicine can be achieved quickly to meet investors' high expectations. If Modena successfully replicates in various cancer types, its product line will no longer be limited to COVID-19, influenza, and respiratory syncytial virus vaccines, thus establishing its long-term commercial value in the field of tumor immunotherapy.