Impact of lenalidomide use among non‐transfusion dependent patients with myelodysplastic syndromes

Chemotherapies approved for defined subgroups promise personalized oncologic care, but their off‐label impact is unclear. Lenalidomide is approved for lower‐risk, transfusion‐dependent (TD) myelodysplastic syndromes (MDS) with del(5q), but frequently used in MDS outside this indication. We characterized lenalidomide use and outcomes among non‐TD patients with MDS. Patients 65 or older diagnosed with MDS between 2007 and 2013 were identified using SEER; linked Medicare claims were evaluated for transfusions, lenalidomide use, and incident toxicities. TD was ≥2 transfusion episodes within an 8‐week period; responses were transfusion independence (TI) and ≥50% transfusion reduction (minor response). We compared overall survival for non‐TD patients receiving lenalidomide versus those not receiving lenalidomide, matched on disease and patient characteristics. We identified 676 patients who had received lenalidomide, including 275 (40.7%) TD and 401 (59.3%) non‐TD; 18.5% (125/676) had zero claims for RBC transfusion prior to receiving lenalidomide. Incident toxicities among patients prescribed lenalidomide were similar in TD and non‐TD groups, except incident thromboembolic events were higher among non‐TD patients (10.8% vs. 6.0%, P = .04). Comparing 191 non‐TD patients receiving lenalidomide within 6 months of MDS diagnosis to risk‐matched MDS controls, lenalidomide was not associated with improved OS (P = .78). Among TD patients (n = 275), 31% achieved TI, and 30% achieved minor hematologic response, with a median time to TI of 4.1 weeks. In conclusion, we confirmed the benefit of lenalidomide among TD patients with MDS; however, many non‐TD patients also received lenalidomide. These patients experienced accompanying toxicity without evidence of benefit in terms of transfusion needs or overall survival.