You will be provided with the titles and abstracts of a collection of medical RCT reports studying a clinical question -- for instance, the efficacy of an intervention on some medical outcome. Please write a few sentences synthesizing the findings of these reports, which could serve as a conclusion section for a systematic review article. Your response should not include any other text. The RCT reports are below.



Title 1:
Improvement in serial cardiopulmonary exercise testing following enzyme replacement therapy in Fabry disease.
Abstract 1:
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.
                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.
                Mean age was 32 years. Mean VO2max was 1.680 +/- 0.67 L/min and increased by 0.459 +/- 0.64 L/min in the patients receiving ERT. Mean VO2max 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.
                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.


Title 2:
Enzyme replacement therapy in Fabry disease: a randomized controlled trial.
Abstract 2:
Fabry disease is a metabolic disorder without a specific treatment, caused by a deficiency of the lysosomal enzyme alpha-galactosidase A (alpha-gal A). Most patients experience debilitating neuropathic pain and premature mortality because of renal failure, cardiovascular disease, or cerebrovascular disease.
                To evaluate the safety and efficacy of intravenous alpha-gal A for Fabry disease.
                Double-blind placebo-controlled trial conducted from December 1998 to August 1999 at the Clinical Research Center of the National Institutes of Health.
                Twenty-six hemizygous male patients, aged 18 years or older, with Fabry disease that was confirmed by alpha-gal A assay.
                A dosage of 0.2 mg/kg of alpha-gal A, administered intravenously every other week (12 doses total).
                Effect of therapy on neuropathic pain while without neuropathic pain medications measured by question 3 of the Brief Pain Inventory (BPI).
                Mean (SE) BPI neuropathic pain severity score declined from 6.2 (0.46) to 4.3 (0.73) in patients treated with alpha-gal A vs no significant change in the placebo group (P =.02). Pain-related quality of life declined from 3.2 (0.55) to 2.1 (0.56) for patients receiving alpha-gal A vs 4.8 (0.59) to 4.2 (0.74) for placebo (P =.05). In the kidney, glomeruli with mesangial widening decreased by a mean of 12.5% for patients receiving alpha-gal vs a 16.5% increase for placebo (P =.01). Mean inulin clearance decreased by 6.2 mL/min for patients receiving alpha-gal A vs 19.5 mL/min for placebo (P =.19). Mean creatinine clearance increased by 2.1 mL/min (0.4 mL/s) for patients receiving alpha-gal A vs a decrease of 16.1 mL/min (0.3 mL/s) for placebo (P =.02). In patients treated with alpha-gal A, there was an approximately 50% reduction in plasma glycosphingolipid levels, a significant improvement in cardiac conduction, and a significant increase in body weight.
                Intravenous infusions of alpha-gal A are safe and have widespread therapeutic efficacy in Fabry disease.


Title 3:
Effects of enzyme replacement therapy on the cardiomyopathy of Anderson-Fabry disease: a randomised, double-blind, placebo-controlled clinical trial of agalsidase alfa.
Abstract 3:
Anderson-Fabry disease is an X-linked glycosphingolipid storage disorder caused by deficient activity of the lysosomal enzyme alpha-galactosidase A. This leads to a progressive accumulation of globotriaosylceramide (Gb(3)) in the lysosomes of cells throughout the body that ultimately results in premature death from renal, cardiac or cerebrovascular complications. Until recently, there was no effective therapy available for this disease. The present study was designed to assess the safety and efficacy of enzyme replacement therapy with agalsidase alfa on the cardiac manifestations of Anderson-Fabry disease.
                The effects of therapy with agalsidase alfa on cardiac structure and function were assessed in a randomised, double-blind, placebo-controlled study of 15 adult male patients with Anderson-Fabry disease. The following parameters were measured at baseline and 6 months: left ventricular mass, QRS duration and levels of Gb(3) in cardiac tissue, urine sediment and plasma. After 6 months of the randomised trial patients were enrolled in a 2-year open-label extension study.
                Left ventricular mass, as measured by MRI, was significantly reduced following 6 months of treatment with agalsidase alfa compared with placebo (p = 0.041). A mean 20% reduction in myocardial Gb(3) content as assessed by serial transvenous endomyocardial biopsies was demonstrated over the 6 months of enzyme replacement compared to a mean 10% increase in patients receiving placebo (p = 0.42)
                Enzyme replacement therapy with agalsidase alfa resulted in regression of the hypertrophic cardiomyopathy associated with Anderson-Fabry disease.


Title 4:
Safety and efficacy of recombinant human alpha-galactosidase A--replacement therapy in Fabry's disease.
Abstract 4:
Fabry's disease, lysosomal alpha-galactosidase A deficiency, results from the progressive accumulation of globotriaosylceramide and related glycosphingolipids. Affected patients have microvascular disease of the kidneys, heart, and brain.
                We evaluated the safety and effectiveness of recombinant alpha-galactosidase A in a multicenter, randomized, placebo-controlled, double-blind study of 58 patients who were treated every 2 weeks for 20 weeks. Thereafter, all patients received recombinant alpha-galactosidase A in an open-label extension study. The primary efficacy end point was the percentage of patients in whom renal microvascular endothelial deposits of globotriaosylceramide were cleared (reduced to normal or near-normal levels). We also evaluated the histologic clearance of microvascular endothelial deposits of globotriaosylceramide in the endomyocardium and skin, as well as changes in the level of pain and the quality of life.
                In the double-blind study, 20 of the 29 patients in the recombinant alpha-galactosidase A group (69 percent) had no microvascular endothelial deposits of globotriaosylceramide after 20 weeks, as compared with none of the 29 patients in the placebo group (P<0.001). Patients in the recombinant alpha-galactosidase A group also had decreased microvascular endothelial deposits of globotriaosylceramide in the skin (P<0.001) and heart (P<0.001). Plasma levels of globotriaosylceramide were directly correlated with clearance of the microvascular deposits. After six months of open-label therapy, all patients in the former placebo group and 98 percent of patients in the former recombinant alpha-galactosidase A group who had biopsies had clearance of microvascular endothelial deposits of globotriaosylceramide. The incidence of most treatment-related adverse events was similar in the two groups, with the exception of mild-to-moderate infusion reactions (i.e., rigors and fever), which were more common in the recombinant alpha-galactosidase A group. IgG seroconversion occurred in 88 percent of patients who received recombinant alpha-galactosidase A.
                Recombinant alpha-galactosidase A replacement therapy cleared microvascular endothelial deposits of globotriaosylceramide from the kidneys, heart, and skin in patients with Fabry's disease, reversing the pathogenesis of the chief clinical manifestations of this disease.


Title 5:
Treatment of Fabry disease: outcome of a comparative trial with agalsidase alfa or beta at a dose of 0.2 mg/kg.
Abstract 5:
Two different enzyme preparations, agalsidase alfa (Replagal(TM), Shire) and beta (Fabrazyme(TM), Genzyme), are registered for treatment of Fabry disease. We compared the efficacy of and tolerability towards the two agalsidase preparations administered at identical protein dose in a randomized controlled open label trial.
                Thirty-four Fabry disease patients were treated with either agalsidase alfa or agalsidase beta at equal dose of 0.2 mg/kg biweekly. Primary endpoint was reduction in left ventricular mass after 12 and 24 months of treatment. Other endpoints included occurrence of treatment failure (defined as progression of cardiac, renal or cerebral disease), glomerular filtration rate, pain, anti-agalsidase antibodies, and globotriaosylceramide levels in plasma and urine. After 12 and 24 months of treatment no reduction in left ventricular mass was seen, which was not different between the two treatment groups. Also, no differences in glomerular filtration rate, pain and decline in globotriaosylceramide levels were found. Antibodies developed only in males (4/8 in the agalsidase alfa group and 6/8 in the agalsidase beta group). Treatment failure within 24 months of therapy was seen in 8/34 patients: 6 male patients (3 in each treatment group) and 2 female patients (both agalsidase alfa). The occurrence of treatment failures did not differ between the two treatment groups; chi(2) = 0.38 p = 0.54.
                Our study revealed no difference in reduction of left ventricular mass or other disease parameters after 12 and 24 months of treatment with either agalsidase alfa or beta at a dose of 0.2 mg/kg biweekly. Treatment failure occurred frequently in both groups and seems related to age and severe pre-treatment disease.
                International Standard Randomized Clinical Trial ISRCTN45178534 [http://www.controlled-trials.com/ISRCTN45178534].


Title 6:
Agalsidase-beta therapy for advanced Fabry disease: a randomized trial.
Abstract 6:
Fabry disease (alpha-galactosidase A deficiency) is a rare, X-linked lysosomal storage disorder that can cause early death from renal, cardiac, and cerebrovascular involvement.
                To see whether agalsidase beta delays the onset of a composite clinical outcome of renal, cardiovascular, and cerebrovascular events and death in patients with advanced Fabry disease.
                Randomized (2:1 treatment-to-placebo randomization), double-blind, placebo-controlled trial.
                41 referral centers in 9 countries.
                82 adults with mild to moderate kidney disease; 74 of whom were protocol-adherent.
                Intravenous infusion of agalsidase beta (1 mg per kg of body weight) or placebo every 2 weeks for up to 35 months (median, 18.5 months).
                The primary end point was the time to first clinical event (renal, cardiac, or cerebrovascular event or death). Six patients withdrew before reaching an end point: 3 to receive commercial therapy and 3 due to positive or inconclusive serum IgE or skin test results. Three patients assigned to agalsidase beta elected to transition to open-label treatment before reaching an end point.
                Thirteen (42%) of the 31 patients in the placebo group and 14 (27%) of the 51 patients in the agalsidase-beta group experienced clinical events. Primary intention-to-treat analysis that adjusted for an imbalance in baseline proteinuria showed that, compared with placebo, agalsidase beta delayed the time to first clinical event (hazard ratio, 0.47 [95% CI, 0.21 to 1.03]; P = 0.06). Secondary analyses of protocol-adherent patients showed similar results (hazard ratio, 0.39 [CI, 0.16 to 0.93]; P = 0.034). Ancillary subgroup analyses found larger treatment effects in patients with baseline estimated glomerular filtration rates greater than 55 mL/min per 1.73 m2 (hazard ratio, 0.19 [CI, 0.05 to 0.82]; P = 0.025) compared with 55 mL/min per 1.73 m2 or less (hazard ratio, 0.85 [CI, 0.32 to 2.3]; P = 0.75) (formal test for interaction, P = 0.09). Most treatment-related adverse events were mild or moderate infusion-associated reactions, reported by 55% of patients in the agalsidase-beta group and 23% of patients in the placebo group.
                The study sample was small. Only one third of the patients experienced clinical events, and some patients withdrew before experiencing any event.
                Agalsidase-beta therapy slowed progression to the composite clinical outcome of renal, cardiac, and cerebrovascular complications and death compared with placebo in patients with advanced Fabry disease. Therapeutic intervention before irreversible organ damage may provide greater clinical benefit.
Six small, poor quality randomised controlled trials provide no robust evidence for use of either agalsidase alfa and beta to treat Anderson-Fabry disease.