Moderna (MRNA) shares skyrocketed in premarket trading on Wednesday, climbing as much as 99% to $125.68 before settling around 87% higher. The surge followed the announcement that its experimental mRNA cancer vaccine, when used alongside Merck's immunotherapy Keytruda, met primary and secondary goals in a late-stage trial for melanoma, the deadliest form of skin cancer.
The positive interim results mark the first successful late-stage readout for Moderna's personalized cancer vaccine, known as Intismeran. The treatment is designed to train the immune system to recognize and attack mutations specific to a patient's tumor. In the phase 3 study, 1,137 patients with high-risk stage IIB to stage IV melanoma who had undergone surgery were randomly assigned to receive either the vaccine plus Keytruda or Keytruda alone for about a year.
According to the companies, the combination reduced the risk of cancer recurrence and also delayed metastasis to other parts of the body, meeting both the primary and secondary endpoints. No new safety signals were observed. The trial remains ongoing, and full results will be presented at an upcoming medical meeting and shared with regulatory authorities.
“Today’s results represent a landmark moment for adjuvant melanoma treatment,” said Professor Georgina Long, the study’s principal investigator and medical director of Melanoma Institute Australia.
Why this matters for Moderna
The news is a critical catalyst for Moderna, which has been seeking to diversify beyond its COVID-19 vaccine franchise. Sales of its coronavirus shot have plummeted as global demand waned, leaving the company searching for new growth drivers. Even after Wednesday's surge, shares remain roughly 75% below their 2021 peak.
Moderna has been building a broader pipeline, including an FDA-approved flu vaccine and experimental shots targeting norovirus and Lyme disease. However, the oncology program has emerged as one of the most closely watched opportunities. Barclays analysts projected last month that the melanoma treatment could generate around $3 billion in annual sales by 2035. Leerink Partners analyst Mani Foroohar had previously described the phase 3 results as a make-or-break event for the stock.
Beyond melanoma: a platform potential
Investors are also looking beyond this single indication. Moderna and Merck are evaluating the personalized vaccine approach in other tumor types, including non-small cell lung cancer, bladder cancer, and renal cell carcinoma. A successful melanoma trial could validate the platform's broader applicability, potentially opening a new revenue stream in the competitive oncology market.
The latest results build on earlier data from a mid-stage study, which showed a 49% reduction in the risk of recurrence or death after five years. The new findings reinforce the potential of combining mRNA technology with checkpoint inhibitors like Keytruda.
Merck's shares also rose more than 7% in premarket trading, reflecting the collaborative nature of the program. The partnership combines Moderna's mRNA expertise with Merck's established immunotherapy franchise.
For Moderna, the outcome is more than a clinical win—it signals that its mRNA platform may have a future beyond the pandemic. As the company continues to navigate a post-COVID landscape, the success of its cancer vaccine could reshape its growth trajectory and investor sentiment.
Melanoma remains a significant public health concern, with over 1.5 million people in the U.S. living with the disease in 2023, according to the National Cancer Institute. The need for effective adjuvant therapies is high, and this combination could offer a new option for patients at high risk of recurrence.
While the stock's dramatic move reflects optimism, the company still faces challenges, including regulatory hurdles and competition from other cancer therapies. However, today's news provides a tangible sign that Moderna's pipeline extends well beyond COVID-19.
This article is for informational purposes only and does not constitute financial advice.
