Clinical effectiveness of DNA methyltransferase inhibitors and lenalidomide in older patients with refractory anemia with ring sideroblasts: a population-based study in the United States.

Existing studies regarding the role of DNA methyltransferase inhibitors (DNMTi) and lenalidomide in refractory anemia with ring sideroblasts (RARS) are limited. Using the surveillance, epidemiology, and end results-medicare database, we assembled a population-based cohort of older adults diagnosed with non-del(5q) lower-risk myelodysplastic syndromes during 2007-2015. Of 2167 patients, 30% had RARS. About 16% of RARS and non- ring sideroblasts (RS) patients received DNMTi. RARS patients were more likely to receive lenalidomide (11.1% vs. 7.1%, p < 0.01). Among patients who were transfusion-dependent at treatment initiation, 55.6% of those treated with DNMTi only and 42.5% treated with lenalidomide only achieved red blood cell transfusion independence (RBC-TI) for a median duration of 21 and 12 weeks, respectively. RS status did not impact rate of RBC-TI. RARS patients had a significantly better survival, and the median survival of RARS patients varied by treatment group. In this population-based study of older RARS patients, DNMTi and lenalidomide were clinically active.

Clinical outcomes of older patients with AML receiving hypomethylating agents: a large population-based study in the United States.

The hypomethylating agents (HMAs) azacitidine and decitabine have been the de facto standard of care for patients with acute myeloid leukemia (AML) who are unfit for intensive therapy. Using the Surveillance, Epidemiology, and End Results-Medicare linked database, we identified 2263 older adults (age ≥66 years) diagnosed with AML during 2005-2015 who received a first-line HMA; 1154 (51%) received azacitidine, and 1109 (49%) received decitabine. Median survival from diagnosis was 7.1 and 8.2 months (P < .01) for azacitidine- and decitabine-treated patients, respectively. Mortality risk was higher with azacitidine vs decitabine (hazard ratio [HR], 1.11; 95% confidence interval [CI], 1.01-1.21; P = .02). The findings were similar when evaluating only patients completing ≥4 cycles (42% of patients treated with either azacitidine or decitabine). These findings lost significance when evaluating those completing a standard 7-day schedule of azacitidine (34%) vs 5-day schedule for decitabine (66%) (HR, 0.95; 95% CI, 0.83-1.08; P = .43). Red blood cell (RBC) transfusion independence (TI) was achieved in one-third of patients with no difference between the 2 HMAs. In conclusion, the majority of older AML patients did not receive the minimum of 4 cycles of HMA often needed to elicit clinical benefit. We observed no clinically meaningful differences between azacitidine- and decitabine-treated patients in their achievement of RBC TI or survival.