Long-term effectiveness of enzyme replacement therapy in Fabry disease: results from the NCS-LSD cohort study

Objectives

To determine the effectiveness of enzyme replacement therapy (ERT) for adults and children with Fabry disease.

Design

Cohort study including prospective and retrospective clinical data. Age- and gender-adjusted treatment effects were estimated using generalised linear mixed models. Treated patients contributed data before and during treatment and untreated patients contributed natural history data.

Participants

Consenting adults (N?=?289) and children (N?=?22) with a confirmed diagnosis of Fabry disease attending a specialist Lysosomal Storage Disorder treatment centre in England. At recruitment 211 adults and seven children were on ERT (range of treatment duration, 0 to 9.7 and 0 to 4.2 years respectively).

Outcome measures

Clinical outcomes chosen to reflect disease progression included left ventricular mass index (LVMI); proteinuria; estimated glomerular filtration rate (eGFR); pain; hearing and transient ischaemic attacks (TIA)/stroke.

Results

We found evidence of a statistically significant association between time on ERT and a small linear decrease in LVMI (p?=?0.01); a reduction in the risk of proteinuria after adjusting for angiotensin-converting enzyme inhibitors and angiotensin receptor blockers (p?p?=?0.01 and p?Conclusions These data provide some further evidence on the long-term effectiveness of ERT in adults with Fabry disease, but evidence of effectiveness could not be demonstrated in children.     

Efficacy of enzyme replacement therapy in Fabry disease

Enzyme replacement therapy has recently been introduced to treat Fabry disease, a rare X-linked lysosomal storage disorder. The disease occurs due to deficient activity of alpha-galactosidase A, leading to progressive accumulation of globotriaosylceramide in multiple organs and tissues. Renal, cardiac and cerebrovascular manifestations of the disease result in premature death in both hemizygous males and heterozygous females. This paper outlines the clinical signs, symptoms and diagnosis of Fabry disease, and the development of the two available enzyme replacement therapies -- agalsidase alfa and agalsidase beta. Agalsidase alfa and agalsidase beta are produced in a human cell line and in Chinese hamster ovary cells, respectively, resulting in products with the same amino acid sequence as the native human enzyme, but with different patterns of glycosylation. Correct post-translational glycosylation is important in terms of the pharmacokinetics, biodistribution, clinical efficacy and tolerability of genetically engineered protein therapeutics. Differences in glycosylation, which may affect immunogenicity and mannose-6-phosphate receptor-mediated cellular internalisation of administered enzyme, possibly account for the differences in dosing, clinical effects and safety profiles reported for agalsidase alfa and agalsidase beta.     

Fabry disease, enzyme replacement therapy and the significance of antibody responses

Fabry disease is an X-linked disorder caused by a deficiency of α-galactosidase A. This leads to a progressive accumulation of globotriaosylceramide in tissues throughout the body. Cardiac, renal and neurological manifestations are common and life expectancy is significantly reduced relative to the general population. Management of Fabry disease involves the administration of intravenous enzyme replacement therapy (ERT). Two forms – agalsidase alfa and agalsidase beta – have been licensed in certain jurisdictions and are generally well tolerated; however, some patients develop antibodies to the infused enzyme, which may impair the efficacy and safety of treatment. Agalsidase alfa and agalsidase beta are produced in different systems; this leads to certain differences in post-translational modification that may affect immunogenicity. Immunoglobulin (Ig) G antibodies have frequently been reported in patients with Fabry disease receiving ERT; IgG responses are reported in a greater proportion of patients receiving agalsidase beta than in patients receiving agalsidase alfa. IgE antibodies are less common than IgG antibodies, and have not been observed in patients receiving agalsidase alfa. However, these data are difficult to interpret due to methodological differences in the assessment of seropositivity, and in the doses of enzyme used. The clinical impact of the development of IgG antibodies to ERT in patients with Fabry disease remains unclear, due to lack of data and to the marked heterogeneity of patients both in terms of disease manifestations and response to therapy. Further studies that examine the development of antibodies in patients with Fabry disease and the potential impact of such antibodies on the outcome of ERT are necessary.     

Raised HDL cholesterol in Fabry disease: Response to enzyme replacement therapy

Fabry disease patients have increased risk of vascular disease despite cardioprotective increased HDL-cholesterol. Enzyme therapy does not significantly alter the lipid profile in the short term.     

Antibiotic therapy in inflammatory bowel disease: a systematic review and meta-analysis

The etiology of inflammatory bowel disease (IBD) is unknown but may relate to an unidentified bacterial pathogen or an immunological reaction to gut microbiota. Antibiotics have therefore been proposed as a therapy for Crohn's disease (CD) and ulcerative colitis (UC) to induce remission in active disease to prevent relapse. Current data are conflicting and we therefore conducted a systematic review of randomized controlled trials (RCTs) evaluating antibiotics in IBD. Only parallel group RCTs were considered eligible. Studies with adult patients receiving any dose of therapy for at least 7 days and up to 16 weeks for active disease, or at least 6 months of follow-up for preventing relapse in quiescent disease were analyzed. We included any antibiotics alone or in combination using predefined definitions of remission and relapse. Two reviewers independently assessed eligibility and extracted data. The primary outcome was remission or relapse using an intention-to-treat methodology. The data were summarized using relative risk (RR) and pooled using a random effects model. For active CD, there were 10 RCTs involving 1,160 patients. There was a statistically significant effect of antibiotics being superior to placebo (RR of active CD not in remission=0.85; 95% confidence interval (CI)=0.73-0.99, P=0.03). There was moderate heterogeneity between results (I(2)=48%) and a diverse number of antibiotics were tested (anti-tuberculosis therapy, macrolides, fluroquinolones, 5-nitroimidazoles, and rifaximin) either alone or in combination. Rifamycin derivatives either alone or in combination with other antibiotics appeared to have a significant effect at inducing remission in active CD. In perianal CD fistula there were three trials evaluating 123 patients using either ciprofloxacin or metronidazole. There was a statistically significant effect in reducing fistula drainage (RR=0.8; 95% CI=0.66-0.98) with no heterogeneity (I(2)=0%) and an number needed to treat 5 (95% CI=3-20). For quiescent CD, there were 3 RCTs involving 186 patients treated with different antibiotics combinations (all including antimycobacterials) vs. placebo. There was a statistically significant effect in favor of antibiotics vs. placebo (RR of relapse=0.62; 95% CI=0.46-0.84), with no heterogeneity (I(2)=0%). In active UC, there were 9 RCTs with 662 patients and there was a statistically significant benefit for antibiotics inducing remission (RR of UC not in remission=0.64; 95% CI=0.43-0.96). There was moderate heterogeneity (I(2)=69%) and antibiotics used were all different single or combination drugs. Antibiotic therapy may induce remission in active CD and UC, although the diverse number of antibiotics tested means the data are difficult to interpret. This systematic review is a mandate for further trials of antibiotic therapy in IBD.     

Improvement of sympathetic skin responses under enzyme replacement therapy in Fabry disease

Summary Aim To report the effect of enzyme replacement therapy (ERT) in sympathetic skin responses (SSR) of patients with Fabry disease. Patients and methods Seven male patients were included in an open-label protocol using agalsidase-alfa, continued at regular intervals. Five patients completed 24 months of ERT and two of them completed 18 months. Two main measurements were performed at baseline, as well as 1 and 2 years after ERT: (1) a standard neurological examination (NE), with a detailed evaluation of the sensory perception of light touch, pinprick, cold, hot, and vibratory stimuli; (2) the SSR amplitudes. Results Although there were no significant differences between NE in this time period, all patients reported general improvement in their subjective reports of acroparaesthesia and sweating. Before starting ERT, the SSR amplitudes were either too small (3/7 patients) or absent (4/7 patients): the average (range) amplitude of 122 μV (0 through 492) was statistically smaller than that found in a control group, i.e. 1453.6 μV (619.7–2754) (p<0.0001, t-test). Mean ± SD SSR amplitude increased to 1088± 690 μV in the second year of ERT, reaching the range found in a normal control group (p=0.004). Conclusion ERT improved SSR continuously in Fabry patients in 2 years of observation. Although the mechanism of the SSR improvement is unknown, this response to ERT can be clinically significant if it reflects a normalization in sweating. Communicating editor: Verena Peters Competing interests: None declared Databases: Fabry disease, OMIM 301500; enzyme α-galactosidase NM 000169     

Enzyme replacement therapy in Fabry disease

Recent clinical trials have demonstrated that enzyme replacement therapy with α-galactosidase A (α-Gal A) constitutes a major clinical advance in the treatment of patients with Fabry disease. This new therapeutic approach has been shown to be well tolerated and effective in reducing levels of the storage product globo-triaosylceramide and in normalizing many of the debilitating manifestations of the disorder. A double-blind placebo-controlled trial in 26 hemizygous male patients showed that agalsidase alfa (human α-Gal A) significantly reduced neuropathic pain (p= 0.02), increased creatinine clearance (p = 0.02), improved glomerular histology, reduced the QRS interval on electrocardiography and increased weight gain. Positron emission tomography also revealed normalization of cerebrovascular flow. After the 6-month controlled period, all patients were given agalsidase alfa for a further12 months. At the end of this period, all patients had a decrease in neuropathic pain, and there was a significant improvement in their ability to sense heat and cold. In addition, renal function stabilized, even in patients with renal insufficiency at the onset of treatment, and patients reported a normalization of sweating and improvements in their level of energy and sense of well-being. These findings show that enzyme replacement therapy offers promise as an effective management strategy for patients with Fabry disease.     

First Polish experience with enzyme replacement therapy in patients with Fabry disease

We report here the course and outcomes of 18-month enzyme replacement therapy in two 43 and 41-year-old brothers with Fabry disease. At 18 months of recombinant alpha-galactosidase A (Fabrazyme) infusions, we observed in the older patient: weight gain, decreased proteinuria (from 4 to 1.5 g/d), stabilization of creatinine clearance, much lower frequency and intensity of angina, and in the younger brother: weight gain, stabilization of creatinine clearance and proteinuria, prolongation of PQ interval and improvement of hearing. However, neurologic manifestations deteriorated over treatment period in both patients. No serious infusion-related side effects were observed.     

Cognitive dysfunction and depression in Fabry disease: a systematic review

Background

Fabry disease, an X-linked lysosomal storage disorder, leads to multi-organ dysfunction, including cerebrovascular disease and psychological disorders. However, the prevalence and pattern of associated cognitive dysfunction is not well understood.

Objectives

To investigate whether there is reliable evidence for neuropsychological impairment in patients with Fabry disease and which cognitive domains are affected. To estimate the prevalence of and factors associated with depression in patients with Fabry disease.

Method

Qualitative systematic review of the literature of studies conducting neuropsychological assessment or measuring the prevalence of depression in adults with Fabry disease using the preferred reporting items for systematic reviews and meta-analysis (PRISMA) guidelines where appropriate.

Results

There is some evidence for neuropsychological impairment in Fabry disease in executive functioning, information processing speed and attention, with preservation of: general intellectual functioning, memory, naming, perceptual functioning and global cognitive functioning. Prevalence rates of depression in Fabry disease ranged from 15 % to 62 %, with the largest study to date reporting a prevalence rate of 46 %. The most common factor associated with depression was neuropathic pain, both directly and indirectly by affecting social and adaptive functioning.

Conclusion

Our review suggests that Fabry disease may be associated with a characteristic pattern of cognitive deficits and a high prevalence of psychological disorders such as depression but highlights the limited available data. Exploring the nature of cognitive impairment in Fabry disease using standardised neuropsychological assessment, brain imaging and measures of depression is an important task for future research.     

Relief of gastrointestinal symptoms under enzyme replacement therapy in patients with Fabry disease

Gastrointestinal symptoms, including diarrhoea and abdominal pain, are one of the earliest and most frequently reported signs of Fabry disease, a rare X-linked lipid storage disorder. As the disease progresses, renal, cardiac and cerebrovascular complications develop, resulting in more serious symptoms and early mortality. The present study evaluated the effects of enzyme replacement therapy (ERT) with agalsidase alfa on the gastrointestinal symptoms of Fabry disease. Following 6 months of treatment, both the severity ( p < 0.02) and frequency ( p < 0.02) of abdominal pain decreased. For those patients who had received agalsidase alfa for more than 6 months, the observed improvement was generally maintained. This is the first study indicating a significant beneficial effect of ERT on gastrointestinal symptoms in a group of patients treated for Fabry disease.     

Improvement in serial cardiopulmonary exercise testing following enzyme replacement therapy in Fabry disease

Summary Background. Fabry disease is an X-linked genetic disorder resulting in the accumulation of glycosphingolipids in various organs, leading to exercise intolerance and early mortality. Enzyme replacement therapy (ERT) has recently been approved for use in Fabry patients. Goals of study. To assess baseline cardiopulmonary exercise characteristics in both invasive and noninvasive tests and to study the impact of ERT on exercise. Methods. A total of 15 patients with Fabry disease underwent baseline cardiopulmonary exercise tests. Six patients were randomized 2:1 to receive either ERT or placebo. We performed serial cardiopulmonary exercise tests at baseline and every 3 months over a period of at least 18 months. The baseline test was compared to the last two exercise tests for each patient. Results. Mean age was 32 years. Mean VO₂ max was 1.680 ± 0.67 L/min and increased by 0.459 ± 0.64 L/min in the patients receiving ERT. Mean VO₂ max was 1.462 ± 0.25 L/min and decreased by 0.116 ± 0.44 L/min in patients on placebo. Mean oxygen pulse (VO₂/HR) increased by 1.71 with enzyme, but increased only 0.025 in patients taking placebo. Estimated stroke volume (SV) increased by 10 ml in patients on ERT. Conclusions. In this small cohort, exercise tolerance increased in patients receiving enzyme replacement therapy. Cardiopulmonary exercise testing is a useful test in measuring the response to therapy in Fabry disease patients. Competing interests: W. R. Wilcox is a paid consultant of Genzyme Corp. and is on the Genzyme Speakers Bureau. Neither he nor his relations own Genzyme stock. Genzyme Corp. provided a research grant for the study     

Iron replacement therapy in inflammatory bowel disease patients with iron deficiency anemia: A systematic review and meta-analysis

Background and aimsIron deficiency anemia (IDA) is a common problem in patients with Inflammatory Bowel Disease (IBD) and has a significant negative impact on quality of life. The aim was to compare the clinical efficacy of intravenous (IV) versus oral (PO) iron replacement in adult IBD with iron deficiency anemia (IDA).MethodsA systematic search for randomized controlled trials comparing the efficacy of IV versus PO iron therapy in the treatment of IDA in adult IBD patients. The primary outcome was the mean change in the hemoglobin at the end of study and secondary outcomes include mean change in ferritin, clinical disease activity index, quality of life score and the adverse reaction rate.ResultsThe search strategy identified 757 articles while only three industry-funded articles met the inclusion criteria for systematic review and meta-analysis. The total sample size was 333 patients with 203 patients receiving IV therapy. IV route was associated with a 6.8 g/L higher mean hemoglobin increment and 110 μg/L higher mean ferritin increment. The IBD activity index and Quality of Life scores were comparable between the two treatment groups. More adverse events were reported in the oral treatment group with the odds for discontinuation being 6.2 (CI 2.2, 17.1).ConclusionsIntravenous iron treatment is better tolerated and more effective than oral iron treatment in improving ferritin. The higher hemoglobin gain with the IV route was small and of uncertain clinical significance. The combined sample size of the included studies was small and further clinical trials are required.     

Accelerated-strategy renal replacement therapy for critically ill patients: A systematic review and meta-analysis

Background:The aim of this study was to investigate the clinical effect and safety of accelerated-strategy initiation of renal replacement therapy (RRT) in critically ill patients.Methods:PubMed, Embase, OVID, EBSCO, and the Cochrane Library databases were searched for relevant articles from inception to December 30, 2020. Only RCTs that compared the clinical efficacy and safety between accelerated-strategy RRT and standard-strategy RRT among critically ill adult patients with acute kidney injury (AKI) were included. The primary outcome was 28-day mortality.Results:A total of 5279 patients in 12 RCTs were included in this meta-analysis. The 28-day mortality rates of patients treated with accelerated and standard RRT were 37.3% (969/2596) and 37.9% (976/2573), respectively. No significant difference was observed between the groups (OR, 0.92; 95% CI, 0.70–1.12; I² = 60%). The recovery rates of renal function were 54.5% and 52.5% in the accelerated- and standard-RRT groups, respectively, with no significant difference (OR, 1.03; 95% CI, 0.89–1.19; I² = 56%). The rate of RRT dependency was similar in the accelerated- and standard-RRT strategies (6.7% vs 5.0%; OR, 1.11; 95% CI, 0.71–1.72; I² = 20%). The accelerated-RRT group displayed higher risks of hypotension, catheter-related infection, and hypophosphatemia than the standard-RRT group (hypotension: OR, 1.26; 95% CI, 1.10–1.45; I² = 36%; catheter-related infection: OR, 1.90; 95% CI, 1.17–3.09; I² = 0%; hypophosphatemia: OR, 2.11; 95% CI, 1.43–3.15; I² = 67%).Conclusions:Accelerated RRT does not reduce the risk of death and does not improve the recovery of kidney function among critically ill patients with AKI. In contrast, an increased risk of adverse events was observed in patients receiving accelerated RRT. However, these findings were based on low quality of evidence. Further large-scale RCTs is warranted.