BACKGROUND: Fabry disease is a rare, X-linked, lifelong progressive lysosomal storage disorder. Severely deficient α-galactosidase A activity in males is associated with the classic phenotype with early-onset, multisystem manifestations evolving to vital organ complications during adulthood. We assessed the ability of 2 low-dose agalsidase beta regimens to lower skin, plasma, and urine globotriaosylceramide (GL-3) levels, and influence clinical manifestations in male pediatric Fabry patients. METHODS: In this multicenter, open-label, parallel-group, phase 3b study, male patients aged 5-18 years were randomized to receive agalsidase beta at 0.5 mg/kg 2-weekly (n = 16) or 1.0 mg/kg 4-weekly (n = 15) for 5 years. All had plasma/urine GL-3 accumulation but no clinically evident organ involvement. The primary outcome was GL-3 accumulation in superficial skin capillary endothelium (SSCE). RESULTS: The mean age was 11.6 (range: 5-18) years and all but one of the 31 patients had classic GLA mutations. In the overall cohort, shifts from non-0 to 0-scores for SSCE GL-3 were significant at years 1, 3, and 5, but results were variable. Plasma GL-3 normalized and urine GL-3 reduced substantially. Higher anti-agalsidase beta antibody titers were associated with less robust SSCE GL-3 clearance and higher urine GL-3 levels. Renal function remained stable and normal. Most Fabry signs and symptoms tended to stabilize; abdominal pain was significantly reduced (-26.3%; P = .0215). No new clinical major organ complications were observed. GL-3 accumulation and cellular and vascular injury were present in baseline kidney biopsies (n = 7). Treatment effects on podocyte GL-3 content and foot process width were highly variable. Fabry arteriopathy overall increased in severity. Two patients withdrew and 2 had their agalsidase beta dose increased. CONCLUSIONS: Our findings increase the limited amount of available data on long-term effects of enzyme replacement therapy in pediatric, classic Fabry patients. The low-dose regimens studied here over a period of 5 years did not demonstrate a consistent benefit among the patients in terms of controlling symptomatology, urine GL-3 levels, and pathological histology. The current available evidence supports treatment of pediatric, classic male Fabry patients at the approved agalsidase beta dose of 1.0 mg/kg 2-weekly if these patients are considered for enzyme replacement therapy with agalsidase beta.

• MeSH
• alfa-galaktosidasa terapeutické užití   MeSH
• dítě MeSH
• enzymová substituční terapie statistika a číselné údaje   MeSH
• Fabryho nemoc farmakoterapie   MeSH
• izoenzymy terapeutické užití   MeSH
• kůže chemie   patologie   MeSH
• lidé MeSH
• mladiství MeSH
• předškolní dítě MeSH
• trihexosylceramidy analýza   MeSH
• výsledek terapie MeSH
• vztah mezi dávkou a účinkem léčiva MeSH
• Check Tag
• dítě MeSH
• lidé MeSH
• mladiství MeSH
• mužské pohlaví MeSH
• předškolní dítě MeSH
• Publikační typ
• časopisecké články MeSH
• klinické zkoušky, fáze III MeSH
• multicentrická studie MeSH
• práce podpořená grantem MeSH
• randomizované kontrolované studie MeSH
• Research Support, N.I.H., Extramural MeSH

TRIAL DESIGN: This analysis characterizes the degree of early organ involvement in a cohort of oligo-symptomatic untreated young patients with Fabry disease enrolled in an ongoing randomized, open-label, parallel-group, phase 3B clinical trial. METHODS: Males aged 5-18 years with complete α-galactosidase A deficiency, without symptoms of major organ damage, were enrolled in a phase 3B trial evaluating two doses of agalsidase beta. Baseline disease characteristics of 31 eligible patients (median age 12 years) were studied, including cellular globotriaosylceramide (GL-3) accumulation in skin (n = 31) and kidney biopsy (n = 6; median age 15 years; range 13-17 years), renal function, and glycolipid levels (plasma, urine). RESULTS: Plasma and urinary GL-3 levels were abnormal in 25 of 30 and 31 of 31 patients, respectively. Plasma lyso-GL-3 was elevated in all patients. GL-3 accumulation was documented in superficial skin capillary endothelial cells (23/31 patients) and deep vessel endothelial cells (23/29 patients). The mean glomerular filtration rate (GFR), measured by plasma disappearance of iohexol, was 118.1 mL/min/1.73 m(2) (range 90.4-161.0 mL/min/1.73 m(2)) and the median urinary albumin/creatinine ratio was 10 mg/g (range 4.0-27.0 mg/g). On electron microscopy, renal biopsy revealed GL-3 accumulation in all glomerular cell types (podocytes and parietal, endothelial, and mesangial cells), as well as in peritubular capillary and non-capillary endothelial, interstitial, vascular smooth muscle, and distal tubules/collecting duct cells. Lesions indicative of early Fabry arteriopathy and segmental effacement of podocyte foot processes were found in all 6 patients. CONCLUSIONS: These data reveal that in this small cohort of children with Fabry disease, histological evidence of GL-3 accumulation, and cellular and vascular injury are present in renal tissues at very early stages of the disease, and are noted before onset of microalbuminuria and development of clinically significant renal events (e.g. reduced GFR). These data give additional support to the consideration of early initiation of enzyme replacement therapy, potentially improving long-term outcome. TRIAL REGISTRATION: ClinicalTrials.gov NCT00701415.

• MeSH
• biopsie MeSH
• cévní endotel patologie   MeSH
• demografie MeSH
• dítě MeSH
• Fabryho nemoc krev   farmakoterapie   patofyziologie   moč   MeSH
• genotyp MeSH
• glykolipidy krev   MeSH
• hodnoty glomerulární filtrace MeSH
• johexol MeSH
• kůže krevní zásobení   MeSH
• kvalita života MeSH
• ledviny patologie   patofyziologie   ultrastruktura   MeSH
• lidé MeSH
• mladiství MeSH
• mozek patologie   MeSH
• mutace genetika   MeSH
• předškolní dítě MeSH
• sfingolipidy krev   MeSH
• trihexosylceramidy krev   genetika   moč   MeSH
• Check Tag
• dítě MeSH
• lidé MeSH
• mladiství MeSH
• mužské pohlaví MeSH
• předškolní dítě MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• randomizované kontrolované studie MeSH

PURPOSE: Fabry disease, a genetic deficiency of alpha-galactosidase A, is characterized by pathogenic cellular accumulation of globotriaosylceramide. During clinical trials, recombinant human alpha-galactosidase A (agalsidase beta; Fabrazyme, Genzyme Corporation, Cambridge, MA), infused intravenously at 1.0 mg/kg every 2 weeks for 6 months, cleared or reduced globotriaosylceramide in renal, cardiac, and dermal microvascular endothelia and other cells, with results sustained for up to 5 years in most patients evaluated. This study explored whether a lower dose could maintain globotriaosylceramide clearance achieved with 1.0 mg/kg. METHODS: Cellular globotriaosylceramide levels were assessed histologically in kidney and skin biopsies from 21 adult Fabry males treated for 6 months at 1.0 mg/kg/2 weeks followed by 18 months at 0.3 mg/kg/2 weeks. RESULTS: In kidney interstitial capillary endothelium, the primary endpoint, globotriaosylceramide clearance was achieved in 100% of patients with 1.0 mg/kg and maintained in 90% with 0.3 mg/kg. In seven other renal cell types and superficial dermal capillary endothelium, globotriaosylceramide reduction or clearance was maintained with 0.3 mg/kg in approximately 70% of patients. CONCLUSIONS: A lower dose of agalsidase beta may be sufficient in some, but not all, patients with Fabry disease to maintain the cellular globotriaosylceramide clearance achieved with 1.0 mg/kg/2 weeks. Long-term clinical effects of transitioning to the lower dose have not been evaluated.

• MeSH
• alfa-galaktosidasa aplikace a dávkování   škodlivé účinky   terapeutické užití   MeSH
• biopsie MeSH
• dospělí MeSH
• endoteliální buňky metabolismus   MeSH
• Fabryho nemoc farmakoterapie   patologie   MeSH
• horečka chemicky indukované   MeSH
• intravenózní infuze MeSH
• izoenzymy aplikace a dávkování   škodlivé účinky   terapeutické užití   MeSH
• kůže metabolismus   patologie   MeSH
• ledviny metabolismus   patofyziologie   patologie   MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladý dospělý MeSH
• mrazení chemicky indukované   MeSH
• následné studie MeSH
• průjem chemicky indukované   MeSH
• trihexosylceramidy krev   metabolismus   moč   MeSH
• vyšetření funkce ledvin MeSH
• výsledek terapie MeSH
• vztah mezi dávkou a účinkem léčiva MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• Publikační typ
• klinické zkoušky MeSH
• multicentrická studie MeSH
• práce podpořená grantem MeSH