Positive association between physical outcomes and patient-reported outcomes in late-onset Pompe disease: a cross sectional study

Exploring Quality of Life in Adults Living With Late-onset Pompe Disease: A Combined Quantitative and Qualitative Analysis of Patient Perceptions from Australia, France, Italy, and the Netherlands

Background: Late-onset Pompe disease (LOPD) is a rare, autosomal recessive metabolic disorder that is heterogeneous in disease presentation and progression. People with LOPD report a significantly lower physical, psychological, and social quality of life (QoL) than the general population. Objectives: This study investigated how individuals' self-reported LOPD status (improving, stable, declining) relates to their QoL. Participant experiences such as use of mobility or ventilation aids, caregivers, symptomology, and daily life impacts were also characterized. Methods: A 2-part observational study was conducted online between October and December 2023 using the 36-item short-form tool (SF-36) and a survey. Adults with LOPD (N=41) from Australia, France, Italy, and the Netherlands were recruited. Results: Participants reporting "declining" LOPD status (56%) had lower physical functioning SF-36 scores than those reporting as "stable" or "improving." Those self-reporting as stable or improving often described an acceptance of declining health in their responses. Physical functioning scores were generally stable in respondents who had been receiving enzyme replacement therapy (ERT) for 1-15 years, but those who had received ERT for >15 years had lower scores. Requiring ventilation and mobility aids had additive negative impacts on physical functioning. Difficulty swallowing, speaking, and scoliosis were the most burdensome symptoms reported by those on ERT for >15-25 years. Discussion: These results demonstrate the humanistic burden of LOPD; through declining physical functioning SF-36 scores over increasing time and increased use of aids, and also through factors related to self-reported LOPD status (where declining status was associated with lower scores) and symptomology variances. Taken holistically, these areas are valuable to explore when informing optimized care. Among a largely declining cohort, even those not self-reporting decline often assumed future deterioration, highlighting the need for improved therapies and the potential to initiate or switch ERT based on evolving symptomology and daily life impacts. Conclusion: Our results indicate that progressing LOPD leads to loss of QoL in ways that relate to time, use of aids, evolving symptomology, and the patient's own perspective. A holistic approach to assessing the individual can help ensure relevant factors are investigated and held in balance, supporting optimized care.

Switching treatment to cipaglucosidase alfa plus miglustat positively affects patient-reported outcome measures in patients with late-onset Pompe disease

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.

Efficacy of avalglucosidase alfa on forced vital capacity percent predicted in treatment-naïve patients with late-onset Pompe disease: A pooled analysis of clinical trials

Background

The efficacy of avalglucosidase alfa (AVA) versus alglucosidase alfa (ALG) on forced vital capacity percent predicted (FVCpp) in patients with late-onset Pompe disease (LOPD) has been assessed in the Phase 3 COMET trial (NCT02782741). Due to the rarity of LOPD and thus small sample size in COMET, additional data were analyzed to gain further insights into the efficacy of AVA versus ALG.

Methods

Data from treatment-naive patients with LOPD were pooled from COMET and Phase 1/2 NEO1/NEO-EXT (NCT01898364/NCT02032524) trials for patients treated with AVA, and Phase 3 LOTS trial (NCT00158600) for patients treated with ALG. Regression analyses using mixed models with repeated measures consistent with those pre-specified in COMET were performed post-hoc. Analyses were adjusted for trials and differences in baseline characteristics. Four models were developed: Model 1 considered all trials; Model 2 included Phase 3 trials; Model 3 included Phase 3 trials and was adjusted for baseline ventilation use; Model 4 included COMET and NEO1/NEO-EXT (i.e., AVA trials only).

Results

Overall, 100 randomized patients from COMET (AVA, n = 51, ALG, n = 49), 60 from LOTS (ALG arm only), and three patients from NEO1/NEO-EXT (who received open-label AVA only) were considered for analysis. Mean age at enrollment was similar across trials (45.3-50.3 years); however, patients from LOTS had a longer mean duration of disease versus COMET and NEO1/NEO-EXT trials (9.0 years and 0.5-2.2 years, respectively) and younger mean age at diagnosis (36.2 years and 44.7-48.6 years, respectively). Least squares mean (95% confidence interval) improvement from baseline in FVCpp at Week 49-52 for AVA versus ALG was 2.43 (-0.13; 4.99) for COMET (n = 98); 2.31 (0.06; 4.57) for Model 1 (n = 160); 2.43 (0.21; 4.65) for Model 2 (n = 157); 2.80 (0.54; 5.05) for Model 3 (n = 154); and 2.27 (-0.30; 4.45) for Model 4 (n = 101).

Conclusions

Models 1 to 3, which had an increased sample size versus COMET, demonstrated a nominally significant effect on FVCpp favoring AVA versus ALG after 1 year of treatment, consistent with results from COMET.

Measuring health related quality of life (HRQoL) in Lysosomal Storage Disorders (LSDs): a rapid scoping review of available tools and domains

BACKGROUND

Lysosomal storage diseases (LSDs) are a group of rare inherited metabolic disorders, consisting of over 70 diseases that are characterised by lysosomal dysfunction. Due to their varied and progressive symptoms, LSDs have a continual impact on patients' health-related quality of life (HRQoL). Several recently published studies have provided insight into the HRQoL of individuals with LSDs. However, it is challenging to meaningfully synthesise this evidence, since studies often focus upon a particular type of LSD and / or utilise different self-report questionnaires or patient-reported outcome measures (PROMs) to assess HRQoL.

AIMS

The aim of this study was to review the published literature in LSDs, to identify the PROMs which have been used to assess HRQoL and generate a conceptual map of HRQoL domains measured in individuals diagnosed with LSDs.

METHODS

Three electronic databases were searched in March 2022. Primary studies of any design which utilised multi-item PROMs to assess at least one aspect of HRQoL in individuals with LSDs since 2017 were identified. Data were extracted to assess both the characteristics of each study and of the PROMs utilised within each study. The extraction of HRQoL domains and synthesis were informed by an a priori framework, inductively modified to reflect data emerging from the identified literature. Selection and extraction was undertaken independently by two reviewers; discrepancies were ratified by a third reviewer.

RESULTS

Sixty nine studies were identified which were published 2017-2022, with a combined total of 52 PROMs (71 variants) used to assess HRQoL in individuals with LSDs. The final extracted HRQoL framework included 7 domains (Activities; Physical sensations; Autonomy; Cognition; Feelings and emotions; Self-identity; Relationships), characterised by 37 sub-domains.

CONCLUSIONS

This review highlights the breadth and variety of HRQoL domains assessed in individuals with LSDs, across three broad domains of physical, psychological and social functioning. The resultant framework and mapped PROMs will aid researchers and clinicians in the selection of PROMs to assess aspects of HRQoL in people living with LSDs, based on their conceptual coverage.

The impact of COVID-19 infection, the pandemic and its associated control measures on patients with Pompe disease

BACKGROUND

Patients with Pompe disease, a rare metabolic myopathy, were thought to be at increased risk of severe COVID-19 disease during the pandemic. In addition, the lockdown may have affected their regular treatment.

OBJECTIVE

To assess the perceived effect of COVID-19 infection and of the pandemic on the treatment, and physical and mental health of patients with Pompe disease.

METHODS

Patients with Pompe disease over 16 years of age participated in an international, cross-sectional, online survey (September 20, 2022-November 7, 2022). The questionnaire, available in eight languages, consisted of 89 questions divided into 3 parts: (A) severity of Pompe disease, (B) COVID-19 precautions and infection(s) and (C) effects of the COVID-19 pandemic.

RESULTS

Among 342 respondents, originating from 25 different countries, 47.6% experienced one or more COVID-19 infections. While most recovered within 4 weeks (69.7%) and only eight patients needed to be admitted to the hospital, 42.2% of patients experienced an impact of the infection on their overall condition, respiratory status and/or mobility status. More severely affected patients took more stringent control measures. The pandemic additionally caused interruptions in medical care in many patients (56.0%) and 17.2% of patients experienced interruptions of enzyme replacement therapy. The pandemic also affected many patients' disease severity (27.7%), mental health (55.4%) and feeling of loneliness (43.4%).

CONCLUSION

COVID-19 infection(s) and the pandemic affected the treatment, physical health and mental health of patients with Pompe disease, emphasizing the importance of continued patient centered care during a difficult time such as the COVID-19 pandemic.

Glycogen storage diseases

Glycogen storage diseases (GSDs) are a group of rare, monogenic disorders that share a defect in the synthesis or breakdown of glycogen. This Primer describes the multi-organ clinical features of hepatic GSDs and muscle GSDs, in addition to their epidemiology, biochemistry and mechanisms of disease, diagnosis, management, quality of life and future research directions. Some GSDs have available guidelines for diagnosis and management. Diagnostic considerations include phenotypic characterization, biomarkers, imaging, genetic testing, enzyme activity analysis and histology. Management includes surveillance for development of characteristic disease sequelae, avoidance of fasting in several hepatic GSDs, medically prescribed diets, appropriate exercise regimens and emergency letters. Specific therapeutic interventions are available for some diseases, such as enzyme replacement therapy to correct enzyme deficiency in Pompe disease and SGLT2 inhibitors for neutropenia and neutrophil dysfunction in GSD Ib. Progress in diagnosis, management and definitive therapies affects the natural course and hence morbidity and mortality. The natural history of GSDs is still being described. The quality of life of patients with these conditions varies, and standard sets of patient-centred outcomes have not yet been developed. The landscape of novel therapeutics and GSD clinical trials is vast, and emerging research is discussed herein.

Association between changes in pulmonary function and in patient reported outcomes during enzyme therapy of adult patients with late-onset Pompe disease

Pompe disease is a rare, progressive, and metabolic myopathy. Reduced pulmonary function is one of the main problems seen in adult patients with late-onset Pompe disease (LOPD). We aimed to explore the association between changes over time in pulmonary function and in patient-reported outcome measures (PROMs), in these patients treated with enzyme replacement therapy (ERT). This is a post hoc analysis of two cohort studies. Pulmonary function was assessed as forced vital capacity in the upright position (FVC_up ). As PROMs, we assessed the physical component summary score (PCS) of the Medical Outcome Study 36-item Short-Form Health Survey (SF-36) and daily life activities (Rasch-Built Pompe-Specific Activity [R-PACT] scale). We fitted Bayesian multivariate mixed-effects models. In the models of PROMs, we assumed a linear association with FVC_up , and adjusted for time (nonlinear), sex, and age and disease duration at the start of ERT. One hundred and one patients were eligible for analysis. PCS and R-PAct were positively associated with FVC_up , while their relation with time was nonlinear (initial increase then decrease). A 1%-point increase in FVC_up is expected to increase PCS by 0.14 points (95% Credible Interval: [0.09;0.19]) and R-PACT by 0.41 points [0.33;0.49] at the same time point. In the first year of ERT, we expect a change of PCS and R-PAct scores by +0.42 and +0.80 points, and in the 5th year of +0.16 and +0.45, respectively. We conclude that the physical domain of quality of life and daily life activities improve when FVC_up increases during ERT.

Quality of Life with Late-Onset Pompe Disease: Qualitative Interviews and General Public Utility Estimation in the United Kingdom

Background: Late-onset Pompe disease (LOPD) is a rare, progressive neuromuscular condition typically characterized by weakness of skeletal muscles, including those involved in respiration and diaphragmatic dysfunction. Individuals with LOPD typically eventually require mobility and/or ventilatory support. Objectives: This study aimed to develop health state vignettes and estimate health state utility values for LOPD in the United Kingdom. Methods: Vignettes were developed for 7 health states of LOPD with states defined in terms of mobility and/or ventilatory support. Vignettes were drafted based on patient-reported outcome data from the Phase 3 PROPEL trial (NCT03729362) and supplemented by a literature review. Qualitative interviews with individuals living with LOPD and clinical experts were conducted to explore the health-related quality-of-life (HRQoL) impact of LOPD and to review the draft vignettes. Vignettes were finalized following a second round of interviews with individuals living with LOPD and used in health state valuation exercises with people of the UK population. Participants rated the health states using the EQ-5D-5L, visual analogue scale, and time trade-off interviews. Results: Twelve individuals living with LOPD and 2 clinical experts were interviewed. Following the interviews, 4 new statements were added regarding dependence on others, bladder control problems, balance issues/fear of falling, and frustration. One hundred interviews with a representative UK population sample were completed. Mean time trade-off utilities ranged from 0.754 (SD = 0.31) (no support) to 0.132 (SD = 0.50) (invasive ventilatory and mobility support-dependent). Similarly, EQ-5D-5L utilities ranged from 0.608 (SD = 0.12) to -0.078 (SD = 0.22). Discussion: The utilities obtained in the study are consistent with utilities reported in the literature (0.670-0.853 for nonsupport state). The vignette content was based on robust quantitative and qualitative evidence and captured the main HRQoL impacts of LOPD. The general public rated the health states consistently lower with increasing disease progression. There was greater uncertainty around utility estimates for the severe states, suggesting that participants found it harder to rate them. Conclusion: This study provides utility estimates for LOPD that can be used in economic modeling of treatments for LOPD. Our findings highlight the high disease burden of LOPD and reinforce the societal value of slowing disease progression.

Application of Patient-Reported Outcome Measurements in Clinical Trials in China

IMPORTANCE

Regulatory authorities, industry peers, and international health policies have emphasized the value of assessing patient-reported outcomes (PROs) in clinical studies. Despite the increase in the number of clinical studies in the last decade in China, little is known about the extent of the use of PROs.

OBJECTIVE

To evaluate the application and characteristics of PRO instruments as primary and secondary outcomes in randomized clinical trials in China.

DESIGN, SETTING, AND PARTICIPANTS

A cross-sectional study of interventional clinical trials conducted in China from January 1, 2010, to December 31, 2020, was performed. Data obtained from the Chinese Clinical Trial Registry and ClinicalTrials.gov databases were evaluated.

MAIN OUTCOMES AND MEASURES

Trials were categorized according to those that (1) precisely listed PRO tools as outcomes, (2) mentioned patient subjective feelings in outcomes but did not clarify which tools were used for assessment, and (3) did not mention any PRO measurements. Data on study phase, setting, participant age, and sex were extracted from trials that considered patient feelings, along with the target diseases and names of the PRO tools.

RESULTS

Among a total of 34 033 trials, 6915 (20.3%) listed the explicit PRO instruments used and 3178 (9.3%) included PRO in their outcomes but did not include the names of the assessment tools. From more than 32 million people included in the registered trials, data on 1.5 million (4.7%) patients were scientifically collected by PRO instruments, and subjective feelings were assessed for 693 867 (2.1%) participants. Pain (16.8%), cancer (15.6%), and musculoskeletal symptoms (13.3%) were the most common conditions for which PROs were precisely collected by tools. The most common tools for PRO measurements were the visual analog scale, Short-Form 36, and Hamilton Depression Scale.

CONCLUSIONS AND RELEVANCE

In this cross-sectional study, the use of PROs increased during the study period in clinical trials conducted in China. However, patient opinion appears to still be rarely measured. The application of PRO is geographically unevenly distributed. Development of PRO instruments, especially those suitable for the Chinese population, may be useful. Further expansion of PROs with respect to the scope of diseases is needed to avoid missing important data.

Six-Minute Walk Distance Is a Useful Outcome Measure to Detect Motor Decline in Treated Late-Onset Pompe Disease Patients

Late-onset Pompe disease (LOPD) is a rare, progressive disorder characterized by limb–girdle muscle weakness and/or respiratory insufficiency, caused by acid alpha-glucosidase (GAA) gene mutations and treated with enzyme replacement therapy. We studied isometric muscle strength in eight muscle groups bilaterally using a Biodex® dynamometer, as well as the Medical Research Council sum score (MRC-SS), hand grip strength, 6 min walk distance (6MWD), 10 m walk test (10MWT) and timed up-and-go test (TUG) in 12 adult, ambulatory, treated LOPD patients and 12 age-/gender-matched healthy controls, every 6 months for 2 years. The mean isometric muscle strength showed a significant decline in right and left knee extensors at 12 months in controls (p < 0.014; p < 0.016), at 18 months in patients (p < 0.010; p < 0.007) and controls (only right side, p < 0.030) and at 24 months in both groups (p < 0.035). The mean 6MWD in patients significantly decreased after 24 months, from 451.9 m to 368.1 m (p < 0.003), whereas in controls, the mean 6MWD significantly increased after 6 months (p < 0.045) and 18 months (p < 0.020) (at 24 months p = 0.054). In patients and controls, the MRC-SS, hand grip test, 10MWT and TUG did not show significant changes (p > 0.05). We conclude that the 6MWD is a useful outcome measure to detect motor decline in treated LOPD patients.

Individualized Assessment of Exercise Capacity in Response to Acute and Long-Term Enzyme Replacement Therapy in Pediatric Pompe Disease

BACKGROUND

Enzyme replacement therapy (ERT) with alglucosidase alfa improves the prospect of patients with infantile-onset Pompe disease (IOPD). However, a progressive decline has been reported. Objective quantification of the response to ERT when assessing newer strategies is warranted.

METHODS

This combined retrospective-prospective study assessed the acute and long-term effects of ERT on exercise in IOPD patients. Evaluation included cardiopulmonary exercise testing (CPET), 6-min walking test (6MWT), spirometry, motor function test (GMFM-88) and enzyme blood levels.

RESULTS

Thirty-four CPETs (17 pre- and 17 two days-post ERT) over variable follow-up periods were performed in four patients. Two days following ERT, blood enzyme levels increased (median, 1.22 and 10.15 μmol/L/h (p = 0.003)). However, FEV1, FVC and GMFM-88, the median 6MWD and the peak VO2 were unchanged. Long-term evaluations showed stabilization in young patients but progressive deterioration in adolescents. Clinical deterioration was associated with more pronounced deterioration in peak VO2 followed in the decreasing order by 6MWD, FVC and GMFM-88.

CONCLUSIONS

The peak VO2 and 6MWD might serve as more sensitive markers to assess clinical deterioration. More studies are needed to clarify the sensitivity of the peak VO2 and 6MWT for quantification of individualized response. This may be important when assessing newer strategies and formulations in IOPD.