Efficacy and Safety of Lenalidomide in Combination With Cyclosporine A in Patients With Myelodysplastic Syndromes

Lenalidomide has shown significant efficacy in the treatment of anemia associated with both 5q- and non 5q- MDS patients. The mechanism(s) of action of lenalidomide in MDS is still to be determined, but given the differences in response rates seen, it is probable that the mechanism is different for patients with 5q- disease compared to non 5q- patients. T-cell mediated activation of intramedullary apoptosis in patients with early MDS leading to impaired hematopoiesis has been well described. Immunomodulation with agents such as ATG, cyclosporine and thalidomide have demonstrated clear activity in some patients with MDS. Lenalidomide, among its many effects, is a potent immunomodulator, which may contribute to its ability to improve red blood cell counts in patients with MDS. It is possible that this effect could be augmented with the addition of cyclosporine A (CSA), in a similar manner to CSA effects in patients with other bone marrow failure syndromes such as aplastic anemia. Subjects will be treated with lenalidomide 10 mg PO daily days 1-28 of a 28-day cycle. Cyclosporine A will be started on day 1 of cycle 2 (day 29) at a dose of 5 mg/kg per day given orally in 2 divided doses. Cyclosporine A levels will be assessed weekly and doses will be adjusted to maintain a serum trough level between 100-450 mg/ml. Patients will continue on therapy for minimum of 16 weeks unless toxicity occurs which precludes continuation on therapy, disease progression and/or patient withdrawal of consent. Patients not achieving response after completing 16 weeks of therapy will discontinue treatment. Patients achieving response will continue therapy until disease progression, unacceptable toxicity or loss of response.