Mark Roberts’s research while affiliated with Salford Royal NHS Foundation Trust and other places

Background Late-onset Pompe disease (LOPD), a rare autosomal recessive multisystemic disorder, substantially impacts patients’ day-to-day activities, outcomes, and health-related quality of life (HRQoL). The PROPEL trial compared cipaglucosidase alfa plus miglustat (cipa+mig) with alglucosidase alfa plus placebo (alg+pbo) in adult patients with LOPD over 52 weeks and showed improved motor and respiratory function in patients switching treatment from standard-of-care enzyme replacement therapy (ERT) to cipa+mig at baseline. This study evaluated the impact of cipa+mig on patient-reported outcomes (PROs), including HRQoL in ERT-experienced patients, using data from PROPEL. Methods PROs evaluated included the Subject’s Global Impression of Change (SGIC), Patient-Reported Outcomes Measurement Information System (PROMIS) Physical Function Short Form 20a, PROMIS Fatigue Short Form 8a, Rasch-built Pompe-specific Activity (R-PAct), and European Quality of Life-5 Dimensions 5 Response Levels (EQ-5D-5L). The proportions of responders in the cipa+mig arm and the alg+pbo arm were compared via chi-squared or Fisher’s exact test (patient-level responder analysis), and least squares (LS) mean differences were calculated for change from baseline at Week 52 of the PRO measures (group-level analysis). Results At Week 52, patient-level SGIC responder and group-level SGIC analyses favored cipa+mig compared with alg+pbo across all SGIC domains (e.g. 90 vs. 59% responders in the cipa+mig vs. the alg+pbo group for SGIC ability to move around; P = 0.0005; and LS mean difference 0.385; P = 0.02). Similarly, PROMIS Physical Function and Fatigue domains numerically favored cipa+mig in both analyses (e.g. 50 vs. 40% responders in the cipa+mig vs. alg+pbo arm for PROMIS Physical Function; P = 0.37; and LS mean difference 3.1; P = 0.11). R-PAct for both treatment groups was similar in the patient-level responder analysis, but numerically favored alg+pbo in the group-level analysis (35% responders in both arms; P = 0.95; and LS mean difference −0.8; P = 0.48). Self-care, usual activities, and depression/anxiety domains of EQ-5D-5L numerically favored cipa+mig in both analyses (e.g. 20 vs. 12% responders in the cipa+mig vs. alg+pbo arm for EQ-5D-5L self-care; P = 0.54; and LS mean difference −0.108; P = 0.52). Conclusions Overall, switching treatment from alglucosidase alfa to cipa+mig positively impacted PRO measurements during the double-blind period of PROPEL. Trial registration NCT03729362; Registration date: November 1, 2018; https://clinicaltrials.gov/study/NCT03729362

Objective Explore the effects of baseline characteristics on long-term safety/efficacy of avalglucosidase alfa (AVA) in subgroups of patients with late-onset Pompe disease enrolled in COMET (Phase 3; NCT02782741). Methods COMET randomised treatment-naïve patients to AVA (n=51) or alglucosidase alfa (ALG; n=49). After a 49-week primary analysis period, all patients from the AVA-arm continued and 44 patients in the ALG-arm switched to AVA (extended treatment period); total duration 145 Weeks. Subgroups and analyses included: 1) the impact of baseline age (≥18–<45y, ≥45y) on the change in 6-minute walk test (6MWT) distance and upright forced vital capacity (FVC) % predicted, 2) the impact of baseline 6MWT (<403.5, ≥403.5m) on the change in FVC % predicted, and 3) the impact of baseline FVC % predicted (<55, ≥55%) on the change in 6MWT distance. Mean estimates (95% CI) were calculated from linear mixed effects models stratified by treatment group. Results Overall, the change from baseline to Week 145 was stable or improved for all subgroups analysed for the different outcomes. From baseline to Week 145: younger patients in the AVA-arm had a significant improvement in 6MWT distance (9.8m [4.4,15.1]; p=0.0004) and AVA-arm patients with baseline FVC ≥55% had a significant improvement in 6MWT distance (6.8m [2.4,11.2]; p=0.0026). Changes over time remained stable in all other subgroups with nonsignificant p values. Conclusions These data indicate that the positive changes seen during treatment with AVA are not driven by any subgroup and demonstrate that AVA is effective in patients with varying baseline characteristics. Funded Sanofi.

Late-onset Pompe Disease (LOPD) is a rare genetic disorder caused by the deficiency of acid alpha-glucosidase leading to progressive cellular dysfunction due to the accumulation of glycogen in the lysosome. The mechanism of relentless muscle damage – a classic manifestation of the disease – has been extensively studied by analysing the whole muscle tissue; however, little, if any, is known about transcriptional heterogeneity among nuclei within the multinucleated skeletal muscle cells. This is the first report of application of single nuclei RNA sequencing to uncover changes in the gene expression profile in muscle biopsies from eight patients with LOPD and four muscle samples from age and gender matched healthy controls. We matched these changes with histology findings using GeoMx Spatial Transcriptomics to compare the transcriptome of control myofibers from healthy individuals with non-vacuolated (histologically unaffected) and vacuolated (histologically affected) myofibers of LODP patients. We observed an increase in the proportion of slow and regenerative muscle fibers and macrophages in LOPD muscles. The expression of the genes involved in glycolysis was reduced, whereas the expression of the genes involved in the metabolism of lipids and amino acids was increased in non-vacuolated fibers, indicating early metabolic abnormalities. Additionally, we detected upregulation of autophagy genes, and downregulation of the genes involved in ribosomal and mitochondrial function leading to defective oxidative phosphorylation. The upregulation of the genes associated with inflammation, apoptosis and muscle regeneration was observed only in vacuolated fibers. Notably, enzyme replacement therapy – the only available therapy for the disease – showed a tendency to restore metabolism dysregulation, particularly within slow fibers. A combination of single nuclei RNA sequencing and spatial transcriptomics revealed the landscape of normal and the diseased muscle, and highlighted the early abnormalities associated with the disease progression. Thus, the application of these two new cutting-edge technologies provided insight into the molecular pathophysiology of muscle damage in LOPD and identified potential avenues for therapeutic intervention.

Background Chronic respiratory insufficiency from progressive muscle weakness causes morbidity and mortality in late-onset Pompe disease (LOPD). Previous Pompe Registry (NCT00231400) analyses for ≤ 5 years’ alglucosidase alfa treatment showed a single linear time trend of stable forced vital capacity (FVC) % predicted. Methods To assess longer term Pompe Registry data, piecewise linear mixed model regression analyses estimated FVC% predicted trajectories in invasive-ventilator-free patients with LOPD aged ≥ 5 years. We estimated annual FVC change 0–6 months, > 6 months–5 years, and > 5–13 years from treatment initiation, adjusting for baseline age, sex, and non-invasive ventilation. Findings Among 485 patients (4612 FVC measurements; 8.3 years median follow-up), median ages at symptom onset, diagnosis, and alglucosidase alfa initiation were 34.3, 41.1, and 44.9 years, respectively. FVC% increased during the first 6 months’ treatment (slope 1.83%/year; 95% confidence interval: 0.66, 3.01; P = 0.0023), then modestly declined −0.54%/year (−0.79, −0.30; P < 0.0001) during > 6 months–5 years, and −1.00%/year (−1.36, −0.63; P < 0.0001) during > 5–13 years. The latter two periods’ slopes were not significantly different from each other (Pdifference = 0.0654) and were less steep than published natural history slopes (−1% to −4.6%/year). Estimated individual slopes were ≥ 0%/year in 96.1%, 30.3%, and 13.2% of patients during the 0–6 month, > 6 month–5 year, and > 5–13 year periods, respectively. Conclusion These real-world data indicate an alglucosidase alfa benefit on FVC trajectory that persists at least 13 years compared with published natural history data. Nevertheless, unmet need remains since most individuals demonstrate lung function decline 5 years after initiating treatment. Whether altered FVC trajectory impacts respiratory failure incidence remains undetermined. Trial registration This study was registered (NCT00231400) on ClinicalTrials.gov on September 30, 2005, retrospectively registered.

Background and purpose Two novel enzyme replacement therapies (ERTs), studied in phase 3 trials in late‐onset Pompe patients, reached marketing authorization by the European Medicines Agency in 2022 and 2023. The European Pompe Consortium (EPOC) updates and extends the scope of the 2017 recommendations for starting, switching and stopping ERT. Methods The European Pompe Consortium consists of 25 neuromuscular and metabolic experts from eight European countries. This update was performed after an in‐person meeting, three rounds of discussion and voting to provide a consensus recommendation. Results The patient should be symptomatic, that is, should have skeletal muscle weakness or respiratory muscle involvement. Muscle magnetic resonance imaging findings showing substantial fat replacement can support the decision to start in a patient‐by‐patient scenario. Limited evidence supports switching ERT if there is no indication that skeletal muscle and/or respiratory function have stabilized or improved during standard ERT of 12 months or after severe infusion‐associated reactions. Switching of ERT should be discussed on a patient‐by‐patient shared‐decision basis. If there are severe, unmanageable infusion‐associated reactions and no stabilization in skeletal muscle function during the first 2 years after starting or switching treatment, stopping ERT should be considered. After stopping ERT for inefficacy, restarting ERT can be considered. Six‐monthly European Pompe Consortium muscle function assessments are recommended. Conclusions The triple‐S criteria on ERT start, switch and stop include muscle magnetic resonance imaging as a supportive finding and the potential option of home infusion therapy. Six‐monthly long‐term monitoring of muscle function is highly recommended to cover insights into the patient's trajectory under ERT.