Aliskiren reduces albuminuria after kidney transplantation

Abstract

Background: The renoprotective effects of agents inhibiting the renin-angiotensin system in renal transplant recipients have been supposed but not finally proven. We performed a double-blind, placebo and losartan controlled, cross-over study to evaluate the influence of aliskiren, direct renin inhibitor on albuminuria and other surrogate markers of kidney injury in patients after renal transplantation. The safety of this therapy was also evaluated. Method: 16 of 18 patients (12M, 4F), 48.3 ± 9.0 years, 57.7 ± 9.1 months after kidney transplantation, with hypertension and stable serum creatinine 1.4±0.08 without proteinuria, completed the protocol. Each patient underwent two 8-week treatment periods (one with aliskiren 150 mg and one with losartan 50 mg) in random order, allowing an 8-week placebo washout between them. Results:  Aliskiren decreased 24h systolic  and 24h diastolic blood pressure as compared to placebo (post hoc: p=0.009 and p=0.003). Aliskiren decreased albuminuria more effectively than placebo as well (post hoc: p=0.032). There were no differences between aliskiren and losartan in these regards. The influence of aliskiren on N-acetyl-β-D-glucosaminidase,  transforming growth factor β-1 and 15-F2t-isoprostanes urine excretions was not significant. Serum potassium, creatinine, eGFR and trough blood cyclosporine or tacrolimus level were unaffected. A significant but not clinically relevant decrease in haemoglobin level after aliskiren was observed. Conclusion: Aliskiren  decreases albuminuria in renal transplant recipients with clinically minimal side effects.