Phase-3 Double-Blind, Placebo-Controlled Study of Pomalidomide in Persons With Myeloproliferative-Neoplasm-Associated Myelofibrosis and RBC-Transfusion-Dependence Myelofibrosis and RBC-Transfusion-Dependence

Study sites in China will also participate in a China-specific, single-arm, open label
extension of the current study. Participants will have myeloproliferative neoplasm
(MPN)-associated myelofibrosis and severe anemia and not be receiving red blood cell
(RBC)-transfusions. Eligible participants will receive pomalidomide (0.5 mg/day) and will be
evaluated on a schedule parallel to that of the global study.

Inclusion Criteria:

- Age ≥18 years

- Myeloproliferative-neoplasm (MPN)-associated myelofibrosis

- RBC-transfusion-dependence

- Bone marrow biopsy within 6 months

- Inappropriate to receive blood cell or bone marrow allotransplant, erythropoietin and
androgenic steroids

- Eastern Cooperative Oncology Group (ECOG) performance score ≤2.

- Agree to follow pregnancy precautions as required by the protocol.

- Agree to receive counseling related to teratogenic and other risks of pomalidomide.

- Agree not to donate blood or semen.

Exclusion Criteria:

- Prior blood cell or bone marrow allotransplant.

- Use of drugs to treat MPN-associated myelofibrosis ≤30 - 42 days before starting study
drug.

- Treatment with erythropoietin or androgenic steroids ≤84 days before starting study
drug.

- Anemia due to reasons other than MPN-associated myelofibrosis.

- Pregnant or lactating females.

- More than 10% blasts by bone marrow examination or more than 10% blasts in blood in
consecutive measurements spanning at least 8 weeks

- Prior history of malignancies,other than the disease being studied, unless the subject
has been free of the malignancy for ≥5 years. Following exceptions:

- Carcinoma in situ of the cervix

- Carcinoma in situ of the breast

- Incidental histologic finding of prostate cancer (T 1a or T 1b using TNM [tumor,
nodes, metastasis] clinical staging system)

- Human Immunodeficiency Virus infection (HIV-infection), active hepatitis B virus (HBV)
or active hepatitis C virus (HCV) infection.

- Prior treatment with pomalidomide.

- Allergic reaction or rash after treatment with thalidomide or lenalidomide

- Any of the following laboratory abnormalities:

- Neutrophils <0.5x10^9 /L

- Platelets <25 x 10^9 /L

- Estimated glomerular filtration rate (kidney function) <30 mL/min/1.73m^2

- Aspartate aminotransferase (AST) and Alanine transaminase (ALT) >3.0 x upper
limit of normal

- Total bilirubin ≥4 x Upper Limit of Normal (ULN);

- Uncontrolled hyperthyroidism or hypothyroidism.

- Deep venous thrombosis (DVT) or pulmonary embolus (PE) <6 months before starting study
drug

- Clinically-important heart disease within the past 6 months