Study of Sotatercept for the Treatment of Chemotherapy Induced Anemia in Patients With Metastatic Breast Cancer (MK-7962-012)

A Phase 2, Double-blind, Randomized, Placebo-Controlled Study of ACE-011 for the Treatment of Chemotherapy Induced Anemia in Patients With Metastatic Breast Cancer

The purpose of this study is to evaluate the percentage of participants in each sotatercept dose regimen who achieve a hematopoietic response during the treatment period including up to 2 months after the last dose of sotatercept treatment of chemotherapy-induced anemia (CIA) in participants with metastatic breast cancer. Hematopoietic response was defined as an increase in hemoglobin concentration of ≥ 1 g/dL relative to baseline for 28 consecutive days during the treatment period including up to 2 months after the last dose of sotatercept in the absence of red blood cell (RBC) transfusion or treatment with an erythropoiesis-stimulating agent (ESA).

Inclusion Criteria:

• Has a histologically confirmed diagnosis of breast cancer documented by cytology or biopsy.
• Has evidence of metastatic breast cancer with a minimum of one lesion per Response Evaluation Criteria in Solid Tumors v 1.1 (RECIST v 1.1) criteria.
• Is receiving a chemotherapy regimen including one of the following: anthracycline, taxane, gemcitabine, vinorelbine or capecitabine.
• Has planned treatment with the same chemotherapy regimen for a minimum of 9 weeks after Day 1 of study intervention administration.
• ≥ 30 days elapsed (from Day 1) since previous treatment with an erythropoiesis stimulating agent (ESA) (including treatment with intravenous (IV) iron) for chemotherapy induced anemia.
• ≥ 7 days elapsed (from Day 1) since the last red blood cell (RBC) transfusion and receipt of ≤ 2 units of blood in the past 30 days.
• Life expectancy of ≥ 6 months.

Exclusion Criteria:

• Has had prior radiation therapy to > 20% of the whole skeleton.
• Has had > 5 prior chemotherapy treatment regimens for metastatic breast cancer.
• Has a history of autoimmune or hereditary hemolysis or gastrointestinal bleeding.
• Has clinically significant pulmonary, endocrine, neurologic, gastrointestinal, hepatic or genitourinary disease unrelated to underlying hematologic disorder.
• Has heart failure as classified by the New York Heart Association (NYHA) classification of 3 or higher.
• Has a recent history of thrombosis, deep vein thrombosis (DVT), pulmonary emboli, or embolic stroke, occurring within the last 6 months.
• Has untreated central nervous system (CNS) metastases or CNS metastases treated with whole brain radiotherapy < 6 months prior to Day 1.
• Has a diagnosis of a myeloid malignancy or known history of myelodysplasia.
• Has a history of second malignancy within 5 years (except excised and cured basal cell carcinoma, squamous cell carcinoma of the skin or cervical carcinoma in situ).
• Has had administration of IV antibiotics or febrile (temperature elevation > 38 ° C) within 14 days of Day 1.
• Has uncontrolled hypertension.
• Has known history of hepatitis B surface antigen (HBsAg and HB core antibody (Ab)), human immunodeficiency virus (HIV) antibody or active hepatitis C.
• Has clinically significant iron (transferrin saturation < 20%), vitamin B12, or folate deficiency.
• Has a history of anemia as a result of inherited hemoglobinopathy such as sickle cell anemia or thalassemia.
• Has a history of autoimmune or hereditary hemolysis; active gastrointestinal bleeding (within the last 6 months as compared to Day 1).
• Has received treatment with another investigational drug or device within 1 month prior to Day 1.
• Is pregnant or lactating.
• Has a history of severe allergic or anaphylactic reactions or hypersensitivity to recombinant proteins or excipients in the investigational product.
• Has had major surgery within 30 days prior to Day 1 (patients must have completely recovered from any previous surgery prior to Day 1).