2024 American Academy of Neurology Abstract Website

Mazen Dimachkie¹, Priya Kishnani², Mary-Alice Abbott³, Antonio Toscano⁴, Meredith Foster⁵, Susan Sparks⁵, Benedikt Schoser⁶
¹University of Kansas Medical Center, ²Department of Pediatrics, Division of Medical Genetics, Duke University Medical Center, ³Baystate Health, ⁴Department of Clinical and Experimental Medicine, Reference Center for Rare Neuromuscular Disorders, University of Messina, ⁵Sanofi, ⁶Department of Neurology, Friedrich-Baur-Institute, Ludwig-Maximilians-University Klinikum München

Objective:

The aim of this analysis is to characterize the demographic and clinical characteristics of infantile-onset (IOPD) and late-onset Pompe disease (LOPD) patients who switched from alglucosidase alfa (ALG) to avalglucosidase alfa (AVA) enrolled in the ongoing international, observational, voluntary Pompe Registry (NCT00231400).

Background:

AVA, a recombinant human acid α-glucosidase enzyme replacement therapy, has received marketing authorization in several countries for IOPD and/or LOPD; US approval: August 2021 for LOPD patients aged ≥1 year.

Design/Methods:

For this analysis, switch patients were defined as having ≥1 ALG record immediately pre-switch to AVA. Demographic and treatment histories were summarized. Respiratory, ambulatory, and biomarker data were assessed pre- and post-switch for LOPD (IOPD was excluded due to small cohort at data cut).

Results:

As of August 4, 2023, 145 LOPD+IOPD switch patients were identified (LOPD, 125 [86.2%]; IOPD, 20 [13.8%]). LOPD: United States, 105 (84.0%); EMEA, 18 (14.4%); JAPAC, 2 (1.6%); female, 60 (48.0%). IOPD: United States, 7 (35.0%); EMEA, 12 (60.0%); JAPAC, 1 (5.0%); female, 12 (60.0%). Patients switched at mean±SD age of 47.4±21.48 (range: 1.0–87.1) years for LOPD and 10.3±5.21 (range: 3.0–20.6) years for IOPD. Most had ≥5 years’ experience on ALG pre-switch (LOPD, 72 [57.6%]; IOPD, 13 [65.0%]). For LOPD, last assessments pre-switch (mean±SD) were upright forced vital capacity % predicted: 60.2±23.98 (n=100), 6-minute walk test: 339.3±157.01 m (n=58), urine glucose tetrasaccharide/hexose tetrasaccharide: 8.2±14.55 mmol/mol creatinine (n=74), and serum creatine kinase: 499.3±399.70 U/L (n=102). Mean changes among LOPD patients with both pre- and up to 1-year post-switch assessments showed stabilization in respiratory and ambulatory function and biomarker improvement.

Conclusions:

The Pompe Registry continues to accrue data for patients switching from ALG to AVA, which will support our understanding of AVA’s effectiveness on respiratory and ambulatory outcomes and biomarker levels in the real-world. [On behalf of the Pompe Registry Sites] Funding: Sanofi.