Thompson: I also read that you recently dosed your first patient in a 200-person trial of a new cancer vaccine. How do your cancer vaccines work?

Türeci: We have two types of mRNA vaccines for cancer. First, we have our off-the-shelf vaccines, where we’ve identified molecular features of tumors that are shared by many patients. These are molecules that are broadly present in cancer cells but not in normal cells. By targeting these molecules, you can fight the cancer without getting collateral damage to healthy cells. Second, we have highly personalized vaccines. We identify cancer mutations that are unique to every patient. Every cancer patient has their own mutations, like a fingerprint. We biopsy the tumor, sequence it, and design a unique, individualized vaccine for each patient.

For both types of therapies, we have shown, in early clinical trials, that they are safe and that the tumors shrink. We have moved our vaccine development into Phase 2 trials for melanoma and head and neck cancers. We have also started our treatment for individualized vaccines for high-risk colorectal cancer.

Thompson: So you’re working on two types of cancer vaccines. Are they meant for different kinds of cancers?

Şahin: For personalized vaccines, we’ve come to think that focusing on the stage after surgery might be best. After surgery to remove a tumor, about 60 percent of patients are cured. But 30 to 40 percent see regrowth of that tumor. Certain cancers, like lung and liver cancer, are particularly likely to relapse post-surgery. mRNA vaccines could be perfectly suited to block this recurrence by specifically targeting the molecules associated with regrowth and metastasis.