Effects of Octreotide-Long-Acting Release Added-on Tolvaptan in Patients with Autosomal Dominant Polycystic Kidney Disease: Pilot, Randomized, Placebo-Controlled, Cross-Over Trial.

BACKGROUND: Tolvaptan and octreotide-long-acting release (LAR) have renoprotective effects in autosomal dominant polycystic kidney disease (ADPKD) that are partially mediated by amelioration of compensatory glomerular hyperfiltration. We compared the effects of tolvaptan and octreotide-LAR combination therapy versus those of tolvaptan monotherapy in patients with ADPKD. METHODS: This pilot, randomized, placebo-controlled, cross-over trial primarily compared the effects of 1- and 4-week treatments with octreotide-LAR (two 20-mg i.m. injections) or placebo (two i.m. 0.9% saline solution injections) added-on tolvaptan (up to 90 and 30 mg/d) on GFR (iohexol plasma clearance) in 19 consenting patients with ADPKD referred to a clinical research center in Italy. Analyses were intention-to-treat. The local ethical committee approved the study. RESULTS: At 4 weeks, GFR significantly decreased by a median (interquartile range) of 3 (-1 to 5) ml/min per 1.73 m2 with tolvaptan and placebo (P=0.01) and by 7 (3-14) ml/min per 1.73 m2 with tolvaptan and octreotide-LAR (P=0.03). GFR changes during the two treatment periods differed by 2 (-5 to 14) ml/min per 1.73 m2 (P=0.28). At 1 week, GFR significantly decreased by 3 (0-7) ml/min per 1.73 m2 with tolvaptan and placebo (P=0.006) and by 10 (-6 to 16) ml/min per 1.73 m2 with tolvaptan and octreotide-LAR add-on therapy (P<0.001). GFR changes during the two treatment periods significantly differed by 3 (0-12) ml/min per 1.73 m2 (P=0.012). Total kidney volume nonsignificantly changed by 4 (-48 to 23) ml with tolvaptan and placebo (P=0.74), whereas it decreased significantly by 41 (25-77) ml with tolvaptan and octreotide-LAR (P=0.001). Changes during the two treatment periods differed by 36 (0-65) ml (P=0.01). Octreotide-LAR also attenuated (P=0.02) the aquaretic effect of tolvaptan. Treatments were well tolerated. CONCLUSIONS: In patients with ADPKD, octreotide-LAR added-on tolvaptan reduced GFR more effectively than octreotide-LAR and placebo. Octreotide-LAR also reduced total and cystic kidney volumes and attenuated the acquaretic effect of tolvaptan. CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER: Tolvaptan-Octreotide LAR Combination in ADPKD (TOOL), NCT03541447.

Achieving remission of proteinuria in childhood CKD.

BACKGROUND: A multidrug treatment strategy that targets urinary proteins with an angiotensin-converting enzyme (ACE) inhibitor and angiotensin receptor blocker (ARB) up-titrated to the respective maximum tolerated dose combined with intensified blood pressure (BP) control has been found to prevent renal function loss in adults with proteinuric nephropathies. Herein, we investigated the effects of this treatment protocol in the pediatric patient population. METHODS: From May 2002 to September 2014 we included in this observational, longitudinal, cohort study 20 consecutive children with chronic nephropathies and 24-h proteinuria of >200 mg who had received ramipril and losartan up-titrated to the respective maximum approved and tolerated doses [mean (standard deviation) dose:2.48 (1.37) mg/m2 and 0.61 (0.46) mg/kg daily, respectively]. The primary efficacy endpoint was a >50 % reduction in 24-h proteinuria to <200 mg (remission). Secondary outcomes included changes in proteinuria, serum albumin, BP, and glomerular filtration rate (GFR). RESULTS: Mean (± standard deviation) patient age at inclusion was 13.8 ± 2.8 years, and the median [interquartile range (IQR)] serum creatinine level and proteinuria were 0.7 (0.6-1.0) mg/dl and 690 (379-1270) mg/24 h or 435 (252-711) mg/m2/24 h, respectively. Proteinuria significantly decreased by month 6 of follow-up, and serum albumin levels increased over a median follow-up period of 78 (IQR 39-105) months. In the nine children who achieved remission, proteinuria reduction persisted throughout the whole follow-up without rebounds. The GFR improved in those children who achieved remission and worsened in those who did not. The mean GFR slopes differed significantly between these two groups (p < 0.05), being positive in those children with remission and negative in those without remission (+0.023 ± 0.15 vs.-0.014 ± 0.23 ml/min/1.73 m2/month, respectively), whereas BP control was similar between the two groups. Hyperkalemia was observed in two children. CONCLUSIONS: Combination therapy with maximum approved doses of ACE inhibitors and ARBs is a safe strategy which may achieve proteinuria remission with kidney function stabilization or even improvement in a substantial proportion of children with proteinuric nephropathies.

Hyperuricemia in kidney transplantation.

Hyperuricemia is a common problem among renal transplant recipients. Its prevalence is clearly attributable to cyclosporine (CsA) use, although individual patients may have other risk factors as well. CsA lowers the urinary clearance of uric acid. The specific mechanism for this is unknown, but may involve alteration in tubular transport. Hyperuricemia may add on to several other factors in contributing to progressive deterioration of graft function and ultimately graft loss. The therapy of hyperuricemia may be particularly challenging in transplant patients.