Humanigen, Inc., formerly KaloBios Pharmaceuticals, Inc., is a biopharmaceutical company. The Company focuses on developing medicines for patients with neglected and rare diseases, with an ancillary focus on pediatric conditions. The Company's product candidate is benznidazole for the treatment of Chagas disease, a parasitic illness that can lead to long-term heart, intestinal and neurological problems. It is engaged in developing monoclonal antibodies, lenzilumab, for the treatment of chronic myelomonocytic leukemia and juvenile myelomonocytic leukemia both of which are rare hematologic cancers. It is exploring development of another of its monoclonal antibodies, ifabotuzumab, for the treatment of rare solid and hematologic cancers. Its KB001-A, is a Humaneered, PEGylated, anti-PcrV modified antibody fragment (Fab) antibody developed for the prevention and treatment of Pseudomonas aeruginosa (Pa), and infections in mechanically ventilated patients and cystic fibrosis (CF).