Patient reported outcomes of patients with Gaucher disease type 1 treated with eliglustat in real-world settings: The ELIPRO study

Introduction: Gaucher disease type 1 (GD1) is a rare genetic lysosomal storage disorder. Eliglustat is a first-line oral therapy for adult patients with GD1. The aim of the ELIPRO (ELIglustat Patient Reported Outcomes) study was to assess real-world outcomes of eliglustat treatment for over 1 year in patients with GD1, with a focus on patient-reported outcomes (PROs), including treatment adherence. Methods: This was a non-interventional, prospective, multicentric study. Patients were stratified according to their previous time on eliglustat: >6 months (Group1) and <= 6 months (Group2). The primary endpoint was adherence to eliglustat, measured by the eight-items Morisky Medication Adherence Scale (MMAS-8; scale of 0-8) at 6 months in Group2. Secondary endpoints were quality of life (QoL) measured by patient input using the European Quality of Life five-dimensional three-level [EQ-5D-3L] questionnaire, fatigue and pain measured by numeric rating scale [NRS; on a scale of 0-10], the evaluation of patient satisfaction level regarding eliglustat treatment measured by Likert scale [scale of 0-7] and treatment adherence at 12 months in both groups. The study also evaluated the safety and effectiveness of eliglustat in the adult GD1 population. Results: Sixty patients with GD1 (approximatively 52% male, mean age: 46.6 +/- 13.9 years) were analyzed: 29 in Group1 and 31 in Group2. GD1 was mostly of mild severity (90%) and 95% of patients had extensive CYP2D6 metabolizer phenotype. Fifty-seven patients had previously received treatment for GD1 (91% enzyme replacement therapy) and 15% were splenectomized. Groups1 and 2 were not necessarily matching for all characteristics. At 6 months, 58% of Group2 patients showed medium adherence (6 < MMAS-8 < 7.75) while 21% showed high adherence (MMAS-8: 8) (mean MMAS-8: 6.7 +/- 1.0); similar results were obtained in Group1 (50% showed high compliance, 35% showed medium compliance; mean MMAS-8: 6.8 +/- 1.4). The mean MMAS-8 for Group1 and Group2 were 7.1 +/- 1.2 (vs 7.0 +/- 1.0 at baseline) and 6.5 +/- 1.0, respectively, at 12 months. At 12 months, the mean NRS scores in Group1 and Group2 were 72.0 +/- 18.5 and 77.3 +/- 13.7 for QoL (vs. 71.7 +/- 18.4 and 80.2 +/- 12.4, respectively at baseline), 4.8 +/- 2.6 and 3.6 +/- 2.7 for fatigue (vs. 4.6 +/- 2.7 and 3.6 +/- 2.6, respectively at baseline) and 3.3 +/- 2.7 and 2.3 +/- 2.3 for pain (vs. 3.3 +/- 2.7 and 2.0 +/- 2.4, respectively at baseline). GD1 assessments (biological, clinical and imaging parameters) remained stable during 12 months in both groups. At the end of the study, majority (97.4%) of patients were satisfied with their treatment with eliglustat (satisfaction score over 5 out of 7). Sixty-six percent of patients (n = 41) experienced mostly mild adverse events (AE) (including four study withdrawals), of whom 27.4% (n = 17) of patients experienced eliglustat-related AEs. Treatment adherence remained stable during 12 months in both groups. Conclusions: Eliglustat treatment compliance was good and sustained, along with overall health state, fatigue and pain levels, which was consistent with overall patients' clinical status. Eliglustat was well tolerated, and had a good safety profile, aligned with a good patient satisfaction. Our study should encourage greater use of PROs for evaluation of impact of the GD treatment on patient's symptoms and well-being.