Zentalis Pharmaceuticals, Inc., formerly Zentalis Pharmaceuticals LLC., is a clinical-stage biopharmaceutical company focused on developing small molecule therapeutics targeting fundamental biological pathways of cancers. It is developing a pipeline of product candidates with a focus on validated oncology targets. Its lead product candidate, ZN-c5, is an oral selective estrogen receptor degrader. ZN-c5 is in a Phase I/II clinical trial for the treatment of estrogen receptor positive, human epidermal growth factor receptor 2-negative. Its other products include ZN-c3, an oral and small molecule inhibitor of WEE1, a protein tyrosine kinase. ZN-c3 is in a Phase I/II clinical trial for the treatment of advanced solid tumors; ZN-d5, a selective inhibitor of B-cell lymphoma 2, in development for the treatment of hematological malignancies; and ZN-e4, an irreversible inhibitor of mutant epidermal growth factor receptor, in a Phase I/II clinical trial for the treatment of cell lung cancer.