Study of Lenzilumab in Previously Treated Patients With Chronic Myelomonocytic Leukemia (CMML)

The purpose of the study is to examine the safety and determine the recommended Phase 2 dose
of lenzilumab when administered to subjects with previously treated CMML who meet the entry
criteria. Study will begin enrollment in July 2016.

Inclusion Criteria:

- Confirmed diagnosis of CMML

- CMML that is refractory to, or progressed following treatment with a hypomethylating
agent or other standard of care treatment

- Eastern Cooperative Oncology Group (ECOG) score ≤ 2

- Able to provide bone marrow biopsy samples

- Acceptable laboratory results

Exclusion Criteria:

- Leukemia other than CMML

- Recent chemotherapy or radiation therapy (within 14 days before first dose of
lenzilumab)

- Concurrent use of human granulocyte-macrophage colony-stimulating factor

- Pregnant or breastfeeding

- Know HIV virus infection

- History of another malignancy within the past 2 years (some skin cancer and prostate
cancers permitted)

- Significant intercurrent illness

- History or current diagnosis of Pulmonary Alveolar Proteinosis or Hypoxemia