TLDR
- Merck and Moderna’s Phase 3 INTerpath-001 trial met its primary endpoint of recurrence-free survival in melanoma patients
- The trial enrolled 1,137 high-risk Stage IIB-IV melanoma patients and is the first large-scale Phase 3 win for mRNA-based cancer vaccines
- MRK stock hit a new 52-week high of $143.52 in premarket trading, up around 10%
- Moderna surged over 90% premarket, trading at $118.61
- Barclays analysts estimate the therapy could generate around $3 billion in melanoma sales by 2035
Merck stock jumped roughly 10% in premarket trading on Wednesday after the company and Moderna announced a major clinical win for their personalized mRNA cancer vaccine.
The Phase 3 INTerpath-001 trial of Intismeran autogene, combined with Keytruda, met its primary endpoint of recurrence-free survival and the secondary endpoint of distant metastasis-free survival in patients with completely resected Stage IIB-IV melanoma.
MRK hit $143.52 in premarket trade, a new 52-week high, clearing the prior ceiling of $137.98.
The trial enrolled 1,137 high-risk patients who had their melanoma surgically removed. Patients received up to nine doses of Keytruda plus the personalized vaccine, or Keytruda alone, for approximately one year. No new safety signals were reported.
This marks the first positive late-stage trial result for an mRNA cancer vaccine and the first study to show a treatment worked better than Keytruda alone in this patient group.
The result follows strong Phase 2b data from January, which showed the combination reduced the risk of recurrence or death by 49% after five years compared to Keytruda alone.
Moderna surged over 90% in premarket trading on the news, hitting $118.61. Moderna was the top trending stock on Stocktwits following the announcement.
Regulatory Talks Coming Soon
Merck’s R&D head Dean Li said on CNBC the companies expect to begin regulatory discussions within the next few months. Moderna CEO Stephane Bancel confirmed no pricing decision has been made yet, noting the data only became available “a couple days ago.”
Bancel also noted that Intismeran does not use patients’ own cells, unlike some cell therapies, which could allow the manufacturing process to scale and potentially bring costs down.
J.P. Morgan analysts said the vaccine launch in adjuvant melanoma will be key to Moderna returning to profitability. Barclays analysts estimate the therapy could reach approximately $3 billion in melanoma sales by 2035.
Analyst Upgrades Added Fuel
The clinical win came on top of a recent run of positive analyst moves. Daiwa upgraded MRK to Outperform from Neutral on August 17, citing pipeline progress. Wells Fargo issued a Buy rating the same day.
William Blair analyst Myles Minter said the interim results position both companies well to seek regulatory approval, and that the data reads positively for ongoing studies in other cancer types. Additional Phase 3 studies in non-small cell lung cancer are still enrolling.
The broader market was little moved on Wednesday, with the S&P 500 up just 0.1% and the Nasdaq fractionally negative, making MRK’s move entirely company-specific.
Merck is currently trading at a new 52-week high of $143.52 as of premarket Wednesday.
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