Enzyme replacement therapy for late-onset Pompe disease.

BACKGROUND: Pompe disease is caused by a deficiency of the enzyme acid alpha-glucosidase (GAA). People with infantile-onset disease have either a complete or a near-complete enzyme deficiency; people with late-onset Pompe disease (LOPD) retain some residual enzyme activity. GAA deficiency is treated with an intravenous infusion of recombinant human acid alglucosidase alfa, an enzyme replacement therapy (ERT). Alglucosidase alfa and avalglucosidase alfa are approved treatments, but cipaglucosidase alfa with miglustat is not yet approved. OBJECTIVES: To assess the effects of enzyme replacement therapies in people with late-onset Pompe disease. SEARCH METHODS: We searched the Cochrane Inborn Errors of Metabolism Trials Register, compiled from electronic database searches and handsearching of journals and conference abstract books. We also searched MEDLINE OvidSP, clinical trial registries, and the reference lists of relevant articles and reviews. Date of last search: 21 April 2022. SELECTION CRITERIA: We included randomised controlled trials (RCTs) of ERT in people with LOPD of any age. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed trial eligibility, extracted data, assessed the risk of bias and the certainty of the evidence (using GRADE). We resolved disagreements through discussion and by consulting a third author. MAIN RESULTS: We included six trials (358 randomised participants) lasting from 12 to 78 weeks. A single trial reported on each comparison listed below. None of the included trials assessed two of our secondary outcomes: need for respiratory support and use of a walking aid or wheelchair. Certainty of evidence was most commonly downgraded for selective reporting bias. Alglucosidase alfa versus placebo (90 participants) After 78 weeks, alglucosidase alfa probably improves the six-minute walk test (6MWT) distance compared to placebo (mean difference (MD) 30.95 metres, 95% confidence interval (CI) 7.98 to 53.92; moderate-certainty evidence) and probably improves respiratory function, measured as the change in per cent (%) predicted forced vital capacity (FVC) (MD 3.55, 95% CI 1.46 to 5.64; moderate-certainty evidence). There may be little or no difference between the groups in occurrence of infusion reactions (risk ratio (RR) 1.21, 95% CI 0.57 to 2.61; low-certainty evidence), quality of life physical component score (MD -1.36 points, 95% CI -5.59 to 2.87; low-certainty evidence), or adverse events (RR 0.94, 95% CI 0.64 to 1.39; low-certainty evidence). Alglucosidase alfa plus clenbuterol versus alglucosidase alfa plus placebo (13 participants) The evidence is very uncertain about the effect of alglucosidase alfa plus clenbuterol compared to alglucosidase alfa plus placebo on: change in 6MWT distance after 52 weeks (MD 34.55 metres, 95% CI-10.11 to 79.21; very low-certainty evidence) and change in % predicted FVC (MD -13.51%, 95% CI -32.44 to 5.41; very low-certainty evidence). This study did not measure infusion reactions, quality of life, and adverse events. Alglucosidase alfa plus albuterol versus alglucosidase alfa plus placebo (13 participants) The evidence is very uncertain about the effect of alglucosidase alfa plus albuterol compared to alglucosidase alfa plus placebo on: change in 6MWT distance after 52 weeks (MD 30.00 metres, 95% CI 0.55 to 59.45; very low-certainty evidence), change in % predicted FVC (MD -4.30%, 95% CI -14.87 to 6.27; very low-certainty evidence), and risk of adverse events (RR 0.67, 95% CI 0.38 to 1.18; very low-certainty evidence). This study did not measure infusion reactions and quality of life. VAL-1221 versus alglucosidase alfa (12 participants) Insufficient information was available about this trial to generate effect estimates measured at one year or later. Compared to alglucosidase alfa, VAL-1221 may increase or reduce infusion-associated reactions at three months, but the evidence is very uncertain (RR 2.80, 95% CI 0.18 to 42.80). This study did not measure quality of life and adverse events. Cipaglucosidase alfa plus miglustat versus alglucosidase alfa plus placebo (125 participants) Compared to alglucosidase alfa plus placebo, cipaglucosidase alfa plus miglustat may make little or no difference to: 6MWT distance at 52 weeks (MD 13.60 metres, 95% CI -2.26 to 29.46); infusion reactions (RR 0.94, 95% CI 0.49 to 1.80); quality of life scores for physical function (MD 1.70, 95% CI -2.13 to 5.53) and fatigue (MD -0.30, 95% CI -2.76 to 2.16); and adverse effects potentially related to treatment (RR 0.83, 95% CI 0.49 to 1.40) (all low-certainty evidence). Cipaglucosidase alfa plus miglustat probably improves % predicted FVC compared to alglucosidase alfa plus placebo (MD 3.10%, 95% CI 1.04 to 5.16; moderate-certainty evidence); however, it may make little or no change in % predicted sniff nasal inspiratory pressure (MD -0.06%, 95% CI -8.91 to 7.71; low-certainty evidence). Avalglucosidase alfa versus alglucosidase alfa (100 participants) After 49 weeks, avalglucosidase alfa probably improves 6MWT compared to alglucosidase alfa (MD 30.02 metres, 95% CI 1.84 to 58.20; moderate-certainty evidence). Avalglucosidase alfa probably makes little or no difference to % predicted FVC compared to alglucosidase alfa (MD 2.43%, 95% CI -0.08 to 4.94; moderate-certainty evidence). Avalglucosidase alfa may make little or no difference to infusion reactions (RR 0.78, 95% CI 0.42 to 1.45), quality of life (MD 0.77, 95% CI -2.09 to 3.63), or treatment-related adverse events (RR 0.92, 95% CI 0.61 to 1.40), all low-certainty evidence. AUTHORS' CONCLUSIONS: One trial compared the effect of ERT to placebo in LOPD, showing that alglucosidase alfa probably improves 6MWT and respiratory function (both moderate-certainty evidence). Avalglucosidase alfa probably improves 6MWT compared with alglucosidase alfa (moderate-certainty evidence). Cipaglucosidase plus miglustat probably improves FVC compared to alglucosidase alfa plus placebo (moderate-certainty evidence). Other trials studied the adjunct effect of clenbuterol and albuterol along with alglucosidase alfa, with little to no evidence of benefit. No significant rise in adverse events was noted with all ERTs. The impact of ERT on some outcomes remains unclear, and longer RCTs are needed to generate relevant information due to the progressive nature of LOPD. Alternative resources, such as post-marketing registries, could capture some of this information.

Thermo-sensitive mitochondrial trifunctional protein deficiency presenting with episodic myopathy.

Mitochondrial trifunctional protein (MTP) is involved in long-chain fatty acid ß-oxidation (lcFAO). Deficiency of one or more of the enzyme activities as catalyzed by MTP causes generalized MTP deficiency (MTPD), long-chain hydroxyacyl-CoA dehydrogenase deficiency (LCHADD), or long-chain ketoacyl-CoA thiolase deficiency (LCKATD). When genetic variants result in thermo-sensitive enzymes, increased body temperature (e.g. fever) can reduce enzyme activity and be a risk factor for clinical decompensation. This is the first description of five patients with a thermo-sensitive MTP deficiency. Clinical and genetic information was obtained from clinical files. Measurement of LCHAD and LCKAT activities, lcFAO-flux studies and palmitate loading tests were performed in skin fibroblasts cultured at 37°C and 40°C. In all patients (four MTPD, one LCKATD), disease manifested during childhood (manifestation age: 2-10 years) with myopathic symptoms triggered by fever or exercise. In four patients, signs of retinopathy or neuropathy were present. Plasma long-chain acylcarnitines were normal or slightly increased. HADHB variants were identified (at age: 6-18 years) by whole exome sequencing or gene panel analyses. At 37°C, LCHAD and LCKAT activities were mildly impaired and lcFAO-fluxes were normal. Remarkably, enzyme activities and lcFAO-fluxes were markedly diminished at 40°C. Preventive (dietary) measures improved symptoms for most. In conclusion, all patients with thermo-sensitive MTP deficiency had a long diagnostic trajectory and both genetic and enzymatic testing were required for diagnosis. The frequent absence of characteristic acylcarnitine abnormalities poses a risk for a diagnostic delay. Given the positive treatment effects, upfront genetic screening may be beneficial to enhance early recognition.

Comprehensive long-term efficacy and safety of recombinant human alpha-mannosidase (velmanase alfa) treatment in patients with alpha-mannosidosis.

INTRODUCTION: Long-term outcome data provide important insights into the clinical utility of enzyme replacement therapies. Such data are presented for velmanase alfa in the treatment of alpha-mannosidosis (AM). METHODS: Patient data (n = 33; 14 adults, 19 paediatric) from the clinical development programme for velmanase alfa were integrated in this prospectively-designed analysis of long-term efficacy and safety. Patients who participated in the phase I/II or phase III trials and were continuing to receive treatment after completion of the trials were invited to participate in a comprehensive evaluation visit to assess long-term outcomes. Primary endpoints were changes in serum oligosaccharide and the 3-minute stair climb test (3MSCT). RESULTS: Mean (SD) treatment exposure was 29.3 (15.2) months. Serum oligosaccharide levels were significantly reduced in the overall population at 12 months (mean change: -72.7%, P < 0.001) and remained statistically significant at last observation (-62.8%, P < 0.001). A mean improvement of +9.3% in 3MSCT was observed at 12 months (P = 0.013), which also remained statistically significant at last observation (+13.8%, P = 0.004), with a more pronounced improvement detected in the paediatric subgroup. No treatment-emergent adverse events were reported leading to permanent treatment discontinuation. CONCLUSIONS: Patients treated with velmanase alfa experienced improvements in biochemical and functional measures that were maintained for up to 4 years. Long term follow-up is important and further supports the use of velmanase alfa as an effective and well-tolerated treatment for AM. Based on the currently available data set, no baseline characteristic can be predictive of treatment outcome. Early treatment during paediatric age showed better outcome in functional endpoints.

Using social media to support small group learning.

BACKGROUND: Medical curricula are increasingly using small group learning and less didactic lecture-based teaching. This creates new challenges and opportunities in how students are best supported with information technology. We explored how university-supported and external social media could support collaborative small group working on our new undergraduate medical curriculum. METHODS: We made available a curation platform (Scoop.it) and a wiki within our virtual learning environment as part of year 1 Case-Based Learning, and did not discourage the use of other tools such as Facebook. We undertook student surveys to capture perceptions of the tools and information on how they were used, and employed software user metrics to explore the extent to which they were used during the year. RESULTS: Student groups developed a preferred way of working early in the course. Most groups used Facebook to facilitate communication within the group, and to host documents and notes. There were more barriers to using the wiki and curation platform, although some groups did make extensive use of them. Staff engagement was variable, with some tutors reviewing the content posted on the wiki and curation platform in face-to-face sessions, but not outside these times. A small number of staff posted resources and reviewed student posts on the curation platform. CONCLUSIONS: Optimum use of these tools depends on sufficient training of both staff and students, and an opportunity to practice using them, with ongoing support. The platforms can all support collaborative learning, and may help develop digital literacy, critical appraisal skills, and awareness of wider health issues in society.

Management of pain in Fabry disease in the UK clinical setting: consensus findings from an expert Delphi panel.

BACKGROUND: Fabry disease is a rare, X-linked inherited lysosomal storage disorder, that manifests as a heterogeneous disease with renal, cardiac and nervous system involvement. The most common pain experienced by people with Fabry disease are episodes of neuropathic pain reported in up to 80% of classical hemizygous male patients and up to 65% of heterozygous female patients. No clear consensus exists within UK clinical practice for the assessment and management of pain in Fabry disease based on agreed clinical practice and clinical experience. Here we describe a modified Delphi initiative to establish expert consensus on management of pain in Fabry disease in the UK clinical setting. METHODS: Delphi panel members were identified based on their demonstrated expertise in managing adult or paediatric patients with Fabry disease in the UK and recruited by an independent third-party administrator. Ten expert panellists agreed to participate in two survey rounds, during which they remained anonymous to each other. Circulation of the questionnaires, and collection and processing of the panel's responses were conducted between September 2021 and December 2021. All questions required an answer. RESULTS: The Delphi panel reached a consensus on 21 out of 41 aspects of pain assessment and management of pain in Fabry disease. These encompassed steps in the care pathway from the goals of therapy through to holistic support, including the use of gabapentin and carbamazepine as first-line analgesic medications for the treatment of neuropathic pain in Fabry disease, as well as the proactive management of symptoms of anxiety and/or depression associated with Fabry pain. CONCLUSIONS: The consensus panel outcomes reported here have highlighted strengths in current UK clinical practice, along with unmet needs for further research and agreement. This consensus is intended to prompt the next steps towards developing clinical guidelines.

Congenital erythropoietic porphyria with two mutations of the uroporphyrinogen III synthase gene (Cys73Arg, Thr228Met).

Congenital erythropoietic porphyria (CEP) is an autosomal recessive inborn error of metabolism that results from the markedly deficient activity of uroporphyrinogen III synthase (UROS). We describe a 14-year-old girl with red urine since infancy, progressive blistering and scarring of the skin, and moderate hemolytic anemia. After years of skin damage, her face is mutilated; she has a bald patch on the scalp, hypertrichosis of the neck, areas of skin darkening, and limited joint movements of the hands. Total urine excretion and fecal total porphyrin were both markedly raised above normal levels. Sequencing of the UROS gene identified two mutations causing CEP (Cys73Arg, Thr228Met). The patient lesions are progressing. Bone marrow transplantation and/or gene therapy are proposed as the next steps in her treatment. In brief, we describe a CEP with confirmed two pathogenic mutations, severe phenotype and discuss the various treatment options available.

Eye movement biomarkers allow for the definition of phenotypes in Gaucher Disease.

BACKGROUND: Neurological forms of Gaucher disease, the inherited disorder of ß-Glucosylceramidase caused by bi-allelic variants in GBA1, is a progressive disorder which lacks a disease-modifying therapy. Systemic manifestations of disease are effectively treated with enzyme replacement therapy, however, molecules which cross the blood-brain barrier are still under investigation. Clinical trials of such therapeutics require robust, reproducible clinical endpoints to demonstrate efficacy and clear phenotypic definitions to identify suitable patients for inclusion in trials. The single consistent clinical feature in all patients with neuronopathic disease is the presence of a supranuclear saccadic gaze palsy, in the presence of Gaucher disease this finding serves as diagnostic of 'type 3' Gaucher disease. METHODS: We undertook a study to evaluate saccadic eye movements in Gaucher patients and to assess the role of the EyeSeeCam in measuring saccades. The EyeSeeCam is a video-oculography device which was used to run a protocol of saccade measures. We studied 39 patients with non-neurological Gaucher disease (type 1), 21 patients with type 3 (neurological) disease and a series of 35 healthy controls. Mean saccade parameters were compared across disease subgroups. RESULTS: We confirmed the saccadic abnormality in patients with type 3 Gaucher disease and identified an unexpected subgroup of patients with type 1 Gaucher disease who demonstrated significant saccade parameter abnormalities. These patients also showed subtle neurological findings and shared a GBA1 variant. CONCLUSIONS: This striking novel finding of a potentially attenuated type 3 Gaucher phenotype associated with a specific GBA1 variant and detectable saccadic abnormality prompts review of current disease classification. Further, this finding highlights the broad spectrum of neuronopathic Gaucher phenotypes relevant when designing inclusion criteria for clinical trials.

Sparking interest in public health amongst future doctors to tackle our NHS sustainability crisis.

This article was migrated. The article was marked as recommended. The new NHS 'Long Term Plan' has a particular focus on the public health issues of disease prevention and reducing health inequalities. However, medical students often perceive public health as abstract and irrelevant to clinical practice. We believe students need to be encouraged to appreciate wider public health issues and ultimately be able to apply clinical and public health tools to achieve change for patients and populations. Our aim is for all medical graduates to be able to apply public health and evidence-based principles to their chosen specialties. In the undergraduate curriculum, we hope to extend problem-, case-, and simulation-based learning into public health education, emphasise the context around statistics and epidemiology teaching, and make the teaching more relevant, tangible and enjoyable. Intercalated BSc students will gain an interdisciplinary perspective by joining Master of Public Health (MPH) students to learn about the prevention and control of disease and the promotion of health and wellbeing. They will also have opportunities to join the new Health Intelligence Team (H.I.T.), on a voluntary reserve list to support Public Health Wales in the event of real investigations. We will evaluate these strategies, and we hope that medical educators worldwide will share their experience of innovative approaches to public health and evidence-based medicine teaching in response to this article, so that public health teaching may be improved.

CD59a deficient mice display reduced B cell activity and antibody production in response to T-dependent antigens.

CD59a is the primary regulator of membrane attack complex in mice. Recently, we have shown that CD59a-deficient (Cd59a-/-) mice exhibit enhanced CD4+ T cell responses. Here, we explored the effects of CD59a on B cell function and antibody production. Contrary to our expectations, Cd59a-/- mice showed a decreased humoral immune response to a T cell dependent antigen, sheep red blood cells. We found that the decreased humoral immune response was associated with a reduction in plasma cell number in vivo and reduced ability to respond to stimuli during in vitro culture experiments. Using MLR studies in which purified wild type or Cd59a-/- CD4+ T cells were mixed with purified B cells from each source, we found that the reduced B cell activation was largely due to the absence of CD59a on CD4+ T cells. Furthermore, a CD59a fusion protein bound specifically to mouse B cells, and enhanced B cell proliferation in a MLR, demonstrating that B cells express an as yet unidentified ligand for CD59a that aids in B cell activation.

p53 regulates cellular resistance to complement lysis through enhanced expression of CD59.

It has been recently hypothesized that the CD59 gene has two putative p53-responsive elements that may be involved in defense of host cells from damage by the complement system in inflammation. Here we have examined the roles of these putative p53-binding sequences within the CD59 gene in regulation of CD59 expression. We have shown that both of these potential responsive elements bind p53 in vitro. Knocking down expression of p53 using small interfering RNA led to a 6-fold decrease in CD59 protein expression in HeLa cells. We have previously observed a decrease of CD59 in camptothecin-induced apoptotic IMR32 cells, whereas expression was increased in the surviving fraction compared with untreated cells. Here, we have shown that these changes are associated with altered expression levels and acetylation status of p53. We have also shown that acetylation status of p53 regulates CD59 expression on cells exposed to inflammatory cytokines to model inflammation. Our data suggest that p53 and in vivo positive/negative regulators of p53 could be used to modulate susceptibility of tumor cells to complement lysis in chemotherapy.

Complement regulator loss on apoptotic neuronal cells causes increased complement activation and promotes both phagocytosis and cell lysis.

In neuroinflammatory disease complement (C) activation and neuronal apoptosis occur in areas of active pathology. C has a role in clearing apoptotic debris, but is also known to cause necrotic cell death by insertion of the membrane attack complex (MAC). It is therefore unclear whether C is protective or injurious in this context. Here we examine C regulator expression and susceptibility to C activation, lysis and phagocytosis in human neuronal cells undergoing apoptosis in order to model the in vivo situation. We demonstrate that apoptotic neuronal lines lose the C regulators CD46 and CD59. Regulator loss occurred only on cells positive for apoptotic markers, and was caspase dependent. Both CD46 and CD59 were shed from cells, CD46 as a soluble form following MMP cleavage, and CD59 on apoptotic blebs and as a soluble form. Apoptotic cells activated C and were opsonised more readily than control cells; as a consequence they were more readily phagocytosed by macrophages than non-apoptotic cells. Susceptibility to C-mediated lysis was complicated in that early cells were more sensitive while late apoptotic cells were more resistant to killing. MMP inhibition protected against the increased lysis seen in early apoptotic cells, but had no effect on susceptibility of non-apoptotic cells to C-mediated lysis. Our studies suggest that C activation on apoptotic neuronal cells is delicately balanced between enhancing their safe disposal through phagocytosis, and triggering necrosis by C-mediated lysis. The data suggest that therapeutic MMP inhibition, by restricting loss of CD46, may limit neuronal damage in neurological disease.

Clinical utility of peri-operative C-reactive protein testing in general surgery.

INTRODUCTION: C-reactive protein (CRP) is an acute-phase protein used clinically to diagnose infectious and inflammatory disease and monitor response to treatment. CRP measurement in the peri-operative period was audited and patterns of change analysed for elective general surgical patients. PATIENTS AND METHODS: General surgical patients (201) admitted for elective general surgery over a 3-month period were considered for the study. CRP results pre- and postoperatively were recorded, and data on co-morbid conditions and surgical procedure were noted. RESULTS: CRP was requested pre-operatively on 84% of patients. A high CRP was more likely to be found in patients with co-morbidity. Postoperatively, CRP was requested during the first 3 days on 69% of patients. CRP peaked at postoperative days two or three, and then fell. In patients who had a high pre-operative CRP, the peak CRP was higher and occurred later, than those who had a normal pre-operative CRP. CONCLUSIONS: CRP requesting pre-operatively is common, but is not recommended in NICE guidelines. Postoperatively, CRP levels rise; as a result, its use as a tool to screen for infection is limited. CRP has a role in diagnosis of infection after the first three postoperative days and in monitoring response to treatment. Therefore, routine use of CRP measurements pre-operatively and in the first 2 or 3 days post-operatively is not recommended. A peri-operative CRP should only be requested if there is a clear clinical indication.

Novel C5a regulators in inflammatory disease.

Complement is part of the innate immune system, acting to protect the host from microorganisms such as bacteria, and other foreign and abnormal cells. Although primarily protective, complement activation can also cause damage to the host. In a number of inflammatory diseases, including rheumatoid arthritis and dermatitis, there is excessive and inappropriate complement activation. Many of the toxic effects seen in these conditions are attributable to the excessive production of the anaphylatoxin C5a, which may contribute to both the initiation and progression of the disease. Therefore, the regulation of C5a production and modulation of its function are good pharmacological targets in these disorders. As yet, there are no effective agents for the therapeutic regulation of C5a in routine clinical practice. This review describes the role of C5a in inflammatory disease, animal models used to study C5a-related effects, and current strategies aimed at regulating C5a. There is also a discussion of the strengths and weaknesses of these approaches, and an outline of the likely progress of this class of drugs in the future.

Beyond lysis: how complement influences cell fate.

Complement is a central component of the innate immune system involved in protection against pathogens. For many years, complement has been known to cause death of targets, either indirectly by attracting and activating phagocytes or directly by formation of a membrane pore, the membrane attack complex. More recently, it has been recognized that complement may cause other 'non-classical' effects that may not directly be aimed at killing of pathogens. Products of complement activation collaborate with the adaptive immune system to enhance responses to antigens. The membrane attack complex of complement, apart from lysing cells, can also trigger diverse events in target cells that include cell activation, proliferation, resistance to subsequent complement attack and either resistance to, or induction of, apoptosis. Various complement products play important roles in signalling for clearance by phagocytes of apoptotic self cells. Here we review some of these non-classical activities of complement and stress the roles that they may play in maintaining the integrity of the organism.