Provided herein are compositions and methods for treating a relapsed or refractory hematologic cancer in a human patient in need thereof. The methods entail administering to the patient a daily dose of about 10 mg to about 75 mg of cerdulatinib or a pharmaceutically acceptable salt thereof, wherein the patients suffer one or more of a B-cell malignancy, chronic lymphocytic leukemia (CLL), follicular lymphoma (FL), diffuse large B-cell lymphoma (DLBCL) or other transformed FL and/or have relapsed or not responded to a prior chemotherapy.
