Shares of Merck and Moderna jumped Tuesday after the drugmakers said a potential skin cancer vaccine they are developing using the same technology behind COVID-19 preventive shots fared well in a small study.
The drugmakers said a combination of the vaccine and Merck's immunotherapy Keytruda led to a statistically significant improvement in recurrence-free survival time in patients with phase three or four melanoma who had tumors removed in surgery.
That combination was compared with Keytruda alone in a mid-stage clinical trial of 157 patients. Patients received either the combination or Keytruda after surgery to remove the tumors.
The treatments continued for about a year in both groups unless the disease came back or side effects became severe.
The patient group that took the potential vaccine and Keytruda saw a 44% reduction in the risk of death or the cancer returning, the companies said.
Merck and Moderna expect to start a phase 3 study of the combination next year, and the companies say they intend to "rapidly expand" their approach to other tumor types. Phase 3 is generally the last and largest clinical study before a drug is submitted to regulators for approval.
The potential vaccine aims to train a patient's immune system to recognize and respond specifically to mutations in the DNA of the patient's tumor. Keytruda, Merck's top seller, primes the body's immune system to detect and fight tumor cells.
Regulators have approved it to treat several types of cancer.
Merck and Moderna established an agreement to work together in 2016, and the companies plan to share costs and profits in their collaboration. Merck also paid Moderna $250 million.
Shares of Cambridge, Massachusetts-based Moderna Inc. jumped 11% in premarket trading. Kenilworth, New Jersey-based Merck & Co. rose nearly 2% and futures indexes climbed.