A noninterventional observational registry of patients with multiple myeloma treated with lenalidomide in Taiwan

Background/purpose: The incidence of multiple myeloma in Asia has risen in the past 30 years. Lenalidomide, an IMiD immunomodulatory agent, has improved the overall survival in patients with relapsed/refractory multiple myeloma (RRMM) when used with dexamethasone versus dexamethasone alone. This observational registry (T-CC-MM-009; NCT01752075) assessed the safety and efficacy of lenalidomide plus dexamethasone in a large Chinese population of patients with RRMM.

Methods: This registry followed the first 100 patients treated with lenalidomide plus dexamethasone in Taiwan. Patients were ≥18 years old and had ≥1 prior treatment. The recommended starting dose for the first four 28-day cycles was 25 mg lenalidomide on days 1-21 and 40 mg dexamethasone on days 1-4, 9-12, and 17-20. Thereafter, dexamethasone was given on days 1-4 only. The primary objective was safety; secondary objectives were efficacy, lenalidomide dosage, and reasons for discontinuation.

Results: The median duration of treatment was 34.6 weeks, and 75.5% completed ≥3 cycles. Most patients (82.7%) experienced ≥1 treatment-related adverse event; the most commonly reported were neutropenia (23.5%), thrombocytopenia (19.4%), anemia (16.3%), fatigue (16.3%), and hypoesthesia (15.3%). Bleeding events (25.5% of patients) were mostly grade 1/2 (80%). Three patients (3%) had venous thromboembolic events. Two invasive second primary malignancies were reported; however, time to onset was <1 year, suggesting they may not be related to lenalidomide. The overall response rate was 34.7%; median time to disease progression was 20.5 months.

Conclusion: These data confirm the safety and efficacy of lenalidomide plus dexamethasone for patients with RRMM in Taiwan.