Lenalidomide and prednisone for myelofibrosis: Eastern Cooperative Oncology Group (ECOG) phase 2 trial E4903

A multicenter Eastern Cooperative Group (ECOG) phase 2 trial assessed whether adding prednisone to lenalidomide would improve previously reported responses in persons with myelofibrosis (MF). Forty-eight subjects with anemia (42 evaluable) received lenalidomide, 10 mg/d, with a 3-month low-dose prednisone taper. Ten subjects received 3 months, and 25 received 6 months of therapy. Myelosup- pression was the main toxicity with 88% with >= grade 3 hematologic toxicity and 45% >= grade 3 nonhematologic toxicity. There were responses in 10 subjects (23%) using the International Working Group for Myelofibrosis Research and Treatment (IWG-MRT)-defined clinical improvement of anemia in 8 (19%) and/or decreased spleen size in 4 (10%). Serial bone marrow analysis showed no resolution of disease-related fibrosis or angiogenesis. With a median follow-up of 2.3 years, 23 subjects are alive. Lenalidomide and prednisone for myelofibrosis evaluated through a multicentered-cooperative group mechanism is only modestly active and myelosuppresive. This study was registered at http://clinicaltrials.gov as NCT00227591. (Blood. 2010;116(22):4436-4438)