Moderna-Merck Cancer Vaccine Shows Promise, but Manufacturing Hurdles Persist

A new personalized cancer vaccine being developed by Moderna and Merck has shown promising results in reducing melanoma recurrence and spread, but its wider use is hindered by manufacturing complexities.

The experimental vaccine, intismeran autogene, targets unique mutations found in an individual patient's tumor. After surgeons remove the tumor or cancerous lesion, the companies sequence it to identify these mutations, which are then used to create a customized mRNA vaccine that trains the immune system to recognize and attack cancer cells.

The vaccine is being tested in combination with Merck's blockbuster immunotherapy Keytruda, and interim data from a large trial show that it met both its primary goal of reducing cancer recurrence and its secondary goal of preventing tumors from spreading. However, the extent of the benefit remains unclear pending the release of detailed results.

The treatment may work best in highly mutated cancers such as melanoma, where abundant tumor-specific mutations provide more targets for the vaccine to attack. Cancers with high mutation rates, such as lung and colon cancer, could also be promising targets. However, it is not clear that the vaccine technology will work against other cancers.