Neutropenia is the most serious hematologic toxicity of cancer chemotherapy, often limiting the doses and density of chemotherapy that can be tolerated. The degree and duration of neutropenia determine the risk of infection. Myelo001, a small orally bioavailable molecule, has been shown in chemotherapy- or radiotherapy-induced myelosuppression to stimulate differentiation of peripheral white blood cells (WBC) and bone marrow cells of the leucocytic, lymphocytic, and erythrocytic lineage. The purpose of the MyeloConcept study is to determine the safety and effectiveness of Myelo001 in preventing or reducing chemotherapy-induced neutropenia and myelosuppression in patients receiving chemotherapy due to breast cancer.