Effect of longacting somatostatin analogue on kidney and cyst growth in autosomal dominant polycystic kidney disease (ALADIN): A randomised, placebo-controlled, multicentre trial

Summary Background Autosomal dominant polycystic kidney disease slowly progresses to end-stage renal disease and has no eff ective therapy. A pilot study suggested that the somatostatin analogue octreotide longacting release (LAR) could be nephroprotective in this context. We aimed to assess the eff ect of 3 years of octreotide-LAR treatment on kidney and cyst growth and renal function decline in participants with this disorder. Methods We did an academic, multicentre, randomised, single-blind, placebo-controlled, parallel-group trial in fi ve hospitals in Italy. Adult (>18 years) patients with estimated glomerular fi ltration rate (GFR) of 40 mL/min per 1·73 m² or higher were randomly assigned (central allocation by phone with a computerised list, 1:1 ratio, stratifi ed by centre, block size four and eight) to 3 year treatment with two 20 mg intramuscular injections of octreotide-LAR (n=40) or 0·9% sodium chloride solution (n=39) every 28 days. Study physicians and nurses were aware of the allocated group; participants and outcome assessors were masked to allocation. The primary endpoint was change in total kidney volume (TKV), measured by MRI, at 1 year and 3 year follow-up. Analyses were by modifi ed intention to treat. This study is registered with ClinicalTrials.gov, NCT00309283. Findings Recruitment was between April 27, 2006, and May 12, 2008. 38 patients in the octreotide-LAR group and 37 patients in the placebo group had evaluable MRI scans at 1 year follow-up, at this timepoint, mean TKV increased signifi cantly less in the octreotide-LAR group (46·2 mL, SE 18·2) compared with the placebo group (143·7 mL, 26·0; p=0·032). 35 patients in each group had evaluable MRI scans at 3 year follow-up, at this timepoint, mean TKV increase in the octreotide-LAR group (220·1 mL, 49·1) was numerically smaller than in the placebo group (454·3 mL, 80·8), but the diff erence was not signifi cant (p=0·25). 37 (92·5%) participants in the octreotide-LAR group and 32 (82·1%) in the placebo group had at least one adverse event (p=0·16). Participants with serious adverse events were similarly distributed in the two treatment groups. However, four cases of cholelithiasis or acute cholecystitis occurred in the octreotide-LAR group and were probably treatment-related. Interpretation These fi ndings provide the background for large randomised controlled trials to test the protective eff ect of somatostatin analogues against renal function loss and progression to end-stage kidney disease. Funding Polycystic Kidney Disease Foundation.