In frail elderly patients with multiple myeloma, starting lenalidomide at low doses was associated with fewer adverse events and less treatment discontinuation, and did not compromise overall response rates, in a single-center, retrospective study conducted in Japan.
Although most of the 56 study patients received 5-10 mg/day of lenalidomide, not the recommended 25-mg/day dose, their overall response rate was 73% (complete response in 17% of patients, very good partial response in 19%, and partial response in 37%), Aya Nakaya, MD, PhD, of Kansai Medical University, Hirakata, and colleagues wrote (Acta Haematol. 2017;138:55-60). In addition, 23% of patients had stable disease and 4% had disease progression. Nine patients developed other types of malignancies during treatment with lenalidomide.
Starting patients on a reduced dose and increasing it gradually while monitoring carefully for adverse events meant that patients did not have to stop treatment, the researchers said. Continuous treatment may improve survival, and “treatment with lenalidomide for long periods of time, even in small doses, may yield favorable outcomes.”
The 30 men and 26 women, mean age 76.5 years, were consecutively diagnosed as transplant-ineligible patients with relapsed/refractory multiple myeloma; 34%, 32%, and 34% had stages I-III disease, respectively. The M-protein consisted of IgG in 52% of patients and IgA in 30%, with Bence-Jones protein detected in 14%.
They were treated with lenalidomide plus dexamethasone at a starting dose determined by the treating physician; 73% were treated with lenalidomide as a second-line regimen and 14% as a third-line regimen. During each 28-day treatment cycle, patients received lenalidomide on days 1-21 and dexamethasone (20 or 40 mg) on days 1, 8, 15, and 22.
The most common starting lenalidomide dose was 10 mg/day (45%), followed by 5 mg/day (21%), 15 mg/day (20%), 20 mg/day (4%), and 25 mg/day (10%). The treatment dose used for the longest period was 10 mg/day (46% of patients), followed by 5 mg/day (25%), 15 mg/day (16%), 20 mg/day (4%), and 25 mg/day (9%).
The most frequent reasons for dose reduction were renal dysfunction (54%), fatigue (20%), hematologic disorder (14%), and rash (9%).
The median treatment period was 9 months (range 1-60 months) and the median follow-up period was 16 months.
The median time to disease progression was 11.8 months (range 8.4-21.9), and the median overall survival was 39.2 months. For those who took 5-10 mg of lenalidomide, the median time to progression was 14.5 months; for those who took lenalidomide at a dose of more than 10 mg, the median time to progression was 8.9 months. The median overall survival of the patients who received a 5- to 10-mg dose of lenalidomide was 38.9 months; the median overall survival of the patients given a dose of more than 10 mg was not available.
The authors declared no competing financial interests in relation to this work.
On Twitter @maryjodales