Treatment of Fabry Disease: Outcome of a Comparative Trial with Agalsidase Alfa or Beta at a Dose of 0.2 mg/kg

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]

A short-term antihypertensive treatment-induced fall in glomerular filtration rate predicts long-term stability of renal function

A short-term antihypertensive treatment-induced fall in glomerular filtration rate predicts long-term stability of renal function. In long-term intervention studies on renal function outcome an initial decline in the glomerular nitration rate (GFR) may occur after starting therapy. If this initial GFR decline is the result of a treatment-induced hemodynamic change reflecting a fall in intraglomerular pressure, it should be reversible after treatment withdrawal, even after long-term treatment. In fact, it could be beneficial for renal function in the long term. We therefore studied systemic and renal hemodynamics in 40 non-diabetic patients with impaired renal function before treatment, during four years treatment with either atenolol or enalapril, and after withdrawal of that treatment. The acute change in GFR 12 weeks after start of treatment varied widely from −11 to +11ml/min (mean ± SD − 1.0 ± 4.1 ml/min, NS). After four years of treatment, withdrawal for 12 weeks resulted in a rise in GFR of +2.2 ± 5.4 ml/min, P = 0.011, again with a wide range of +14 to −6 ml/min). The initial fall in GFR was related to the rise after withdrawal (r = 0.32, P < 0.05). Interestingly, the acute treatment induced change in GFR correlated with the long-term slope, such that a patient with a greater initial decline in GFR showed a more stable course during the follow up (r = −0.36, P < 0.05). The patients were arbitrarily divided in group A (N = 20), with the largest initial treatment-induced fall in GFR, and group B (N = 20), with the smallest initial fall in GFR. Group A had a significantly less steep slope than group B (−0.41 ± 1.52 vs. −2.09 ± 2.79 ml/min/year, P = 0.023) during the four year follow-up. I B (−0.41 ± 1.52 vs. −2.09 ± 2.79 ml/n group A GFR increased again after withdrawal of treatment (+3.8 ± 5.6 ml/min, P = 0.011) whereas it did not change in group B (+0.5 ± 4.0 ml/min, NS). As a consequence, GFR post-treatment was not different compared to pre-treatment in group A (−2.5 ± 7.2 ml/min, NS), whereas it was 5.9 ± 12.1ml/min lower in group B (P = 0.023). Patients treated with enalapril had a similar response as patients treated with atenolol. In conclusion, an initial fall in GFR after starting antihypertensive treatment in patients with a mild to moderate renal function impairment (GFR 30 to 90 ml/min) is reversible even after years of treatment, suggesting that this therapy-induced fall is of hemodynamic and not of structural origin. This initial GFR fall was associated with a subsequent stable renal function. These data lead to the hypothesis that the initial fall in GFR in response to antihypertensive therapy reflects renal protection