Safety and efficacy of administering the maximal dose of candesartan in renal transplant recipients

Background The regular dose of an angiotensin II type-1 receptor blocker (ARB) in renal transplant patients for hypertension is shown to be safe and effective; however, information on the appropriate dosing of ARBs in renal transplant patients is limited. We evaluate the efficacy and safety of the maximal dose of candesartan administered to renal transplant patients. Methods Sixty-nine recipients were enrolled in this study. Patients were divided into three groups based on the basal dose of candesartan: patients not taking candesartan (Group A); patients taking a low to medium dose of candesartan (2–4 mg/day; Group B); and patients taking a high dose of candesartan (8 mg/day; Group C). During the course of the study, the dose of candesartan was gradually increased to a final dose of 12 mg/day. Physiological and biochemical parameters were measured before and after the 12-month study period. Results Ninety-one percent of patients succeeded in continuing their administration of candesartan for 1 year and 75% tolerated the administration of the maximal dose of candesartan. Significant differences in proteinuria, albuminuria, serum creatinine, and estimated glomerular filtration rate (eGFR) level among the groups were detected. In Group A, candesartan reduced systolic blood pressure, decreased the levels of proteinuria, albuminuria, eGFR, and hemoglobin and increased plasma potassium, creatinine level, and plasma renin activity. Conclusion The gradual increase of an ARB to its maximal dose in renal transplant patients is safe when carefully monitored. We were able to demonstrate the impact of maximal renin-angiotensin system (RAS) blockade on both proteinuria and albuminuria, which indicates the need for future, long-term randomized prospective trials to further establish the impact of maximal RAS blockade on renal and cardiovascular protection in transplant patients.