In the past few years, scientists have opened a new chapter in cancer treatment with designer drugs that can mobilize the immune system against tumors.
Immunotherapy has shown impressive results in some patients with advanced lung cancer, melanoma, and a few other cancers — but it helps only a minority of people. To date, immunotherapy hasn’t been very effective against such cancers as breast, prostate, and pancreatic, and it’s also not yet possible to predict with any certainty whether an individual patient will benefit from immunotherapy treatment.
In addition to drugs that block immune checkpoints such as PD-1 and PD-L1 – which, in effect, release brakes on the immune system’s T-cell defenders so they can recognize and attack tumors – immunotherapies include CAR T cells, cancer treatment vaccines, and cancer-killing viruses.
Immunotherapy can be dramatically successful for people with limited options, so scientists are hard at work trying to understand why most tumors don’t respond to it. Scientists also are also looking into the possibility of converting resistant tumors into tumors that are more vulnerable to immunotherapy.
