An experimental immune therapy conducted on a single breast cancer patient has captured a great deal of attention this week. The 49-year-old woman, Judy Perkins, had metastatic breast cancer that had spread throughout her body. The disease had not responded to a variety of previous treatments, and her doctors expected her to only live a few more months.
Personalized Immune Therapy:
Then, researchers at the National Cancer Institute initiated a brand new form of immune therapy (Zacharakis et al, Nature Medicine, June 4, 2018). They harvested specific immune cells from her tumors. These tumor-infiltrating lymphocytes, or TILs, were encouraged to multiply in the laboratory.
While the immune cells were growing outside her body, the clinicians gave Ms. Perkins one of the new immunotherapy drugs called pembrolizumab (Keytruda). This checkpoint inhibitor modified her immune system so that when her own natural T-cells (the TILs) were re-injected into her body they could attack the tumors. That is precisely what they did. More than three years later she is still alive and well with no signs of breast cancer. She has gone back to her active outdoor lifestyle, including a kayak race around the state of Florida.
Will This Kind of Super Immune Therapy Help Other Cancer Patients?
Researchers hope they will be able to repeat this very personalized treatment for other patients. At this point, however, that goal is uncertain. Widespread clinical trials of this type of very personalized immune therapy are a long way off. Two other women who underwent the TIL treatment at the same time as Ms. Perkins did not survive.
Such treatments are likely to be very expensive. Some cancer patients are already taking a different but related treatment called CAR-T (for chimeric antigen receptor T-cell therapy). FDA-approved CAR-T treatments can cost hundreds of thousands of dollars.
