[Early phase II trial of bestrabucil in hematological malignancies]

Thirty-three patients with various hematological malignancies were treated with Bestrabucil, the benzoate of an estradiol-chlorambucil conjugate, at doses of 50-300 mg daily p.o., consecutively. Nineteen patients had previously received chemotherapy. Of 29 evaluable patients, there were one CR and three PRs among 6 patients with chronic lymphocytic leukemia, two CRs and one PR among 4 patients with malignant lymphoma, two PRs among 3 patients with adult T-cell leukemia, one PR among 4 patients with macroglobulinemia, one PR for one patient with essential thrombocythemia, and one PR for a patient with chronic myelocytic leukemia. Main side effects included G1 symptoms (14%), estradiol-related symptoms (24%) and myelosuppression (32%).