90-month muscle function and biomarker outcomes of cipaglucosidase alfa+miglustat in adults with Pompe disease: open-label phase I/II ATB200-02 study

Topic:

Clinical Management

Poster Number: 80 S

Author(s):

Paula R Clemens, MD, University of Pittsburgh, Benedikt Schoser, MD, Friedrich-Baur-Institute at the Department of Neurology, LMU University Hospital, LMU Munich, Drago Bratkovic, MBBS, PARC Research Clinic, Royal Adelaide Hospital, Barry Byrne, MD, PhD, University of Florida, Ozlem Goker-Alpan, MD, Lysosomal and Rare Disorders Research and Treatment Center, Priya S Kishnani, MD, Duke University Medical Center, Mark Roberts, MD, Salford Royal NHS Foundation Trust, Nadine AME van der Beek, MD, Erasmus MC University Medical Center, Farah Amon, MS, Amicus Therapeutics, Inc., Alberto di Ronza, PhD, Amicus Therapeutics, Brian Fox, PhD, Amicus Therapeutics, Inc., Fred Holdbrook, PhD, Amicus Therapeutics, Inc., Vipul Jain, MS, Amicus Therapeutics, Inc., Tahseen Mozaffar, MD, University of California, Irvine

Background: Pompe disease is a progressive disorder characterized by a deficiency of acid α-glucosidase.

Objectives: ATB200-02 (NCT02675465) evaluated cipaglucosidase alfa plus miglustat (cipa+mig) in adults with Pompe disease. We report muscle function and biomarker outcomes up to month 90.

Methods: The study included four patient cohorts: three ambulatory (two enzyme replacement therapy [ERT]-experienced [2-6 years and ≥7 years] and one ERT-naïve) cohorts and one non-ambulatory ERT-experienced cohort. All patients received cipa+mig (20 mg/kg intravenous + 260 mg oral) biweekly. Assessments included 6-minute walk distance (6MWD); Gait, Stairs, Gowers’ maneuver, Chair (GSGC); 10-meter walk test; timed up and go; quantitative/manual muscle testing; creatine kinase (CK); urinary hexose tetrasaccharide (Hex4); and safety.

Results: Twenty-nine patients enrolled (ERT-experienced ambulatory: n=17; ERT-naïve ambulatory: n=6; ERT-experienced non-ambulatory: n=6); 24 completed the study, with five discontinuations. In ambulatory patients, mean (standard deviation [SD]) baseline % predicted 6MWD was 60.2 (16.20) % and 67.8 (12.61) % for ERT-experienced and ERT-naïve groups, respectively. Mean (SD) change from baseline (CFBL) to month 60 was +4.8 (9.08) % and −1.5 (19.71) %, and +2.7 (9.20) % and +0.9 (15.00) % to month 90. Mean (SD) GSGC score improved from 14.3 (5.23) and 12.8 (3.55) at baseline in ERT-experienced and ERT-naïve ambulatory patients to month 60 (mean [SD] CFBL −1.2 [5.41] and −0.8 [2.32]) and month 90 (−1.2 [4.49] and −0.5 [2.12]). ERT-experienced and ERT-naïve ambulatory patients had improvements in mean (SD) percent CFBL in CK (−46.5 [12.13] % and −53.8 [10.03] %) and Hex4 (−20.3 [47.28] % and −2.3 [133.95] %) at month 90. Non-ambulatory ERT-experienced patients had improvements in CK and Hex4 at month 60 (mean [SD] percent CFBL −12.3 [43.91] % and −2.9 [25.32] %); 90-month data not available.

Conclusions: Cipa+mig was generally well tolerated up to month 90. Across Pompe disease populations, long-term treatment with cipa+mig demonstrated durable stability or improvements in multiple muscle function outcomes and biomarker levels over 7.5 years, with consistent trends despite the inherent variability of small patient cohorts, especially at later time points. Supported by Amicus Therapeutics, Inc. Submitted to WORLDSymposium 2026, San Diego, CA, USA.