Apexigen Inc., a clinical-stage biopharmaceutical company, discovers and develops antibody therapeutics for oncology. It develops a pipeline of product candidates, including APX005M, a humanized agonist antibody that is in Phase II clinical development for the treatment of solid tumors, such as melanoma, esophageal and gastroesophageal junction, sarcoma, and rectal and ovarian cancers in combination with immunotherapy, chemotherapy, radiation therapy, and cancer vaccines; and APX601, a humanized antagonist antibody that is in Phase I/II clinical trial for the treatment of multiple tumor indications, as well as APX801, an NK cell engager to activate natural killer cells to killing of tumor cells. The company was founded in 2010 and is based in San Carlos, California.