The FDA granted a Fast Track designation to Calithera Biosciences’ CB-839 in combination with everolimus, for the treatment of patients with metastatic renal cell carcinoma who have received two or more prior lines of therapy.

CB-839 is a an inhibitor of glutaminase that is being evaluated in Phase I/II clinical trials for the treatment of solid tumors, including renal cell carcinoma, triple-negative breast cancer, non-small cell lung cancer and melanoma.

CB-839 takes advantage of the pronounced dependency many cancers have on the nutrient glutamine for growth and survival.