The clinical utility of lenalidomide in multiple myeloma and myelodysplastic syndromes

Purpose. The pharmacology, pharmacokinetics, pharmacodynamics, clinical utility, adverse effects, dosage, and cost of lenalidomide are reviewed. Summary. Lenalidomide is a thalidomide analogue approved for treatment of myelodysplastic syndromes (MDS) associated with a cytogenetic 5q deletion. In combination with dexamethasone, lenalidomide has been approved by the FDA in the United States for the treatment of relapsed or refractory multiple myeloma, and is sometimes used for induction therapy. Although the precise mechanism of action of lenalidomide remains unknown, it does exhibit antineoplastic and immunomodulatory properties. Lenalidomide is quickly absorbed after oral administration and is renally eliminated. In patients with myelodysplatic syndromes, lenalidomide reduces the need for transfusion. In patients with refractory or relapsed multiple myeloma, lenalidomide in combination with dexamethasone demonstrated a significantly longer time to tumor progression compared to placebo plus dexamethasone. Lenalidomide in combination with dexamethasone also elicited an objective response from patients with newly diagnosed symptomatic multiple myeloma. Treatment with lenalidomide was associated with neutropenia, thrombocytopenia, constipation, pruritus, and fatigue. Due to the teratogenic nature of thalidomide, lenalidomide must be obtained through a restrictive distribution program. The initial daily dosing of lenalidomide is 10 mg for MDS with a 5q deletion and 25 mg for relapsed or refractory multiple myeloma. Dose modifications are required for renal impairment and grade 3—4 adverse events. Conclusion. Lenalidomide is an effective agent for the treatment of MDS with a 5q deletion and relapsed or refractory multiple myeloma.