There are numerous reasons for immunotherapy to fail or for cancer in general to be able to fight against your body and survive. One important mechanism is Myeloid Derived Suppressor Cells (MDSC). These are immune cells that can actually protect cancer. As described in this article, a new method to target these using a drug that is already FDA approved (Mylotarg) can enhance the success of immunotherapy such as immune check-point inhibitors (Keytruda, Opdivo, Yervoy) and also CAR-.
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