Eliglustat is a first-line oral therapy for adults with Gaucher disease type 1 (GD1) with extensive, intermediate, or poor CYP2D6-metabolizer phenotypes (90% of patients). We report real-world outcomes after 2 years of eliglustat therapy in the International Collaborative Gaucher Group Gaucher Registry (NCT00358943). As of January 2019, baseline and 2-year data (±1 year) were available for 231 eliglustat-treated GD1 patients: 19 treatment-naïve (0 splenectomized) and 212 ERT patients who switched to eliglustat (36 splenectomized). Most patients (89%) were from the United States, where eliglustat was first approved. In treatment-naïve patients, mean hemoglobin increased from 12.4 to 13.4 g/dL (P=0.004, n=18), mean platelet count increased from 113 to 156 x109/L (P<0.0001, n=17); mean spleen volume decreased from 7.4 to 3.5 multiples of normal (MN) (P=0.02, n=7); mean liver volume remained normal (n=7); median spine Z-score was unchanged (-1.3 to -1.2, n=6). In non-splenectomized switch patients, mean hemoglobin remained stable/non-anemic (n=167); mean platelet count remained stable/normal (n=165); mean spleen volume decreased from 3.3 to 2.8 MN (P=0.0009, n=64); mean liver volume remained normal (n=63); median lumbar spine Z-score improved from -0.7 to -0.4 (P=0.014, n=68). In splenectomized switch patients, mean hemoglobin remained stable/non-anemic (n=31); mean platelet count increased from 297 to 324 x109 /L (non-significant, n=29); mean liver volume remained normal (n=13); median spine Z-score improved from -0.8 to -0.6 (non-significant, n=11). Median chitotriosidase decreased in all groups (P<0.01 for all). These real-world results are consistent with eliglustat clinical trial results demonstrating long-term benefit in treatment-naïve patients and stability in ERT switch patients. This article is protected by copyright. All rights reserved.