Moderna and Merck officially announced that their personalized genetic vaccine combined with Keytruda reduced the risk of melanoma relapse or death by 42% in a Phase 3 trial, despite Moderna shares plunging 25% following an early data leak.
Sharp stock decline following early vaccine data leak ahead of medical conference
Details of the leaked results emergence and comparison with previous studies
Official confirmation of Phase 3 results in the Interpath 001 trial
Upcoming scientific presentation in Madrid and publication in the New England Journal
Frequently asked questions
Sharp stock decline following early vaccine data leak ahead of medical conference
Shares of biotechnology company Moderna dropped by up to 25% during Thursday trading, while shares of its pharmaceutical partner Merck declined by 3.9%. This steep price slide began after results for the personalized melanoma vaccine developed by the two companies, scientifically known as intisimeran autogene, appeared online two days before their scheduled official reveal at a major cancer conference, according to Bloomberg.
Leaked preliminary numbers showed the vaccine works effectively, though the statistical benefit appeared slightly smaller than that recorded in a previous, smaller study. Investors had driven Moderna shares up strongly over the year based on optimistic expectations for this treatment program.
Details of the leaked results emergence and comparison with previous studies
According to Investing.com, the results appeared by mistake on the medical news website Oncology Central at approximately 12:30 PM Eastern Time before being removed shortly afterward. Unverified accounts on the X platform then circulated a report attributed to the medical site stating that the vaccine reduced the risk of cancer recurrence or death by 42%, though the link attached to the posts no longer worked, per Bloomberg.
A previous mid-stage study had shown a 49% risk reduction, but that earlier trial involved a different group of patients over a different time period, making a direct comparison between the two results scientifically inaccurate. A Moderna spokesperson initially declined to comment on the leak, according to MarketWatch.
Official confirmation of Phase 3 results in the Interpath 001 trial
Later on Thursday, Merck and Moderna officially released detailed results from the Phase 3 trial named Interpath 001. The trial proved that combining the personalized vaccine with Merck’s immunotherapy drug Keytruda reduced the risk of disease recurrence or death by 42% compared to using Keytruda alone, and also reduced the risk of distant metastasis or death by 38% after a median follow-up of 24.6 months, according to a joint statement from the companies.
After two years of treatment, 82.2% of patients who received the combination therapy remained alive without any relapse, compared to 70% in the group that received Keytruda alone. The trial included 1,137 patients with surgically resected melanoma, while overall survival data was not yet mature. The companies confirmed they are in discussions with regulatory authorities. Reuters noted that this study is the first to prove that a vaccine built from unique genetic mutations specific to each patient’s tumor, when combined with immunotherapy, can keep the disease under control, while Wall Street analysts noted that investors were looking for at least a 40% reduction in relapse risk. CNBC reported that the stock fell despite the full results appearing positive compared to those expectations, and oncologists described the results to STAT as an important step forward.
Upcoming scientific presentation in Madrid and publication in the New England Journal
The two companies announced last August that the trial had met its primary endpoints without disclosing any detailed figures at the time. Researcher Georgina Long is scheduled to present the full data during the European Society for Medical Oncology congress in Madrid, Spain, on Saturday, October 24, at 10:30 AM Eastern Time.
Moderna will host an investor webcast later that day, and the companies announced that the study results have been accepted for scientific publication in the New England Journal of Medicine.
Frequently asked questions
Question: What is the main result of the Phase 3 Moderna and Merck melanoma vaccine trial?
Answer: The Interpath 001 trial of 1,137 patients showed that combining intisimeran autogene with Keytruda reduced the risk of cancer recurrence or death by 42% and the risk of distant spread by 38% after a median follow-up of 24.6 months.
Question: Why did Moderna shares fall 25% on Thursday?
Answer: Shares dropped after results leaked early on Oncology Central two days before the Madrid conference, and some traders compared the 42% figure to a smaller previous study result of 49%.
Question: What is the relapse-free survival rate for patients after two years of combination therapy?
Answer: 82.2% of patients who received the vaccine with Keytruda remained alive without disease recurrence after two years, compared to 70% for those who received Keytruda alone.
Question: When and where will the full study data be officially presented?
Answer: Researcher Georgina Long will present the full data at the European Society for Medical Oncology congress in Madrid on Saturday, October 24, and the study has been accepted for publication in the New England Journal of Medicine.
