Albuminuria-lowering effect of dapagliflozin alone and in combination with saxagliptin and effect of dapagliflozin and saxagliptin on glycaemic control in patients with type 2 diabetes and chronic kidney disease (DELIGHT): a randomised, double-blind, placebo-controlled trial

Abstract

Background: In patients with type 2 diabetes, intensive glucose control can be renoprotective and albuminuria-lowering treatments can slow the deterioration of kidney function. We assessed the albuminuria-lowering effect of the sodium-glucose co-transporter-2 inhibitor dapagliflozin with and without the dipeptidyl peptidase-4 inhibitor saxagliptin, and the effect of dapagliflozin-saxagliptin on glycaemic control in patients with type 2 diabetes and moderate-to-severe chronic kidney disease.

Methods: In this double-blind, placebo-controlled trial (DELIGHT), we enrolled patients at 116 research centres in Australia, Canada, Japan, South Korea, Mexico, South Africa, Spain, Taiwan, and the USA. We included patients with a known history of type 2 diabetes, increased albuminuria (urine albumin-to-creatinine ratio [UACR] 30-3500 mg/g), an estimated glomerular filtration rate of 25-75 mL/min per 1·73 m², and an HbA_1c of 7·0-11·0% (53-97 mmol/mol), who had been receiving stable doses of angiotensin-converting enzyme inhibitor or angiotensin II receptor blocker therapy and glucose-lowering treatment for at least 12 weeks. After a 4-week, single-blind placebo run-in period, participants were randomly assigned (1:1:1; via an interactive voice-web response system) to receive dapagliflozin (10 mg) only, dapagliflozin (10 mg) and saxagliptin (2·5 mg), or placebo once-daily for 24 weeks. Primary endpoints were change from baseline in UACR (dapagliflozin and dapagliflozin-saxagliptin groups) and HbA_1c (dapagliflozin-saxagliptin group) at week 24 in all randomly allocated patients with available data (full analysis set). This study is registered with ClinicalTrials.gov, number NCT02547935 and is completed.

Findings: The study took place between July 14, 2015, and May 18, 2018. 1187 patients were screened, of whom 461 were randomly assigned: 145 to the dapagliflozin group, 155 to the dapagliflozin-saxagliptin group, and 148 to the placebo group (13 patients were excluded because of data integrity issues). Dapagliflozin and dapagliflozin-saxagliptin reduced UACR versus placebo throughout the study period. At week 24, the difference (vs placebo; n=134 patients with available data) in mean UACR change from baseline was -21·0% (95% CI -34·1 to -5·2; p=0·011) for dapagliflozin (n=132) and -38·0% (-48·2 to -25·8; p<0·0001) for dapagliflozin-saxagliptin (n=139). HbA_1c was reduced in the dapagliflozin-saxagliptin group (n=137) compared with the placebo group (n=118) at week 24 (-0·58% [-0·80 to -0·37; p<0·0001]). The numbers of patients with adverse events (79 [54%] in the dapagliflozin group, 104 [68%] in the dapagliflozin-saxagliptin group, and 81 [55%] in the placebo group) or serious adverse events (12 [8%], 12 [8%], and 16 [11%], respectively) were similar across groups. There were no new drug-related safety signals.

Interpretation: Dapagliflozin with or without saxagliptin, given in addition to angiotensin-converting enzyme inhibitor or angiotensin II receptor blocker treatment, is a potentially attractive option to slow the progression of kidney disease in patients with type 2 diabetes and moderate-to-severe chronic kidney disease.

Funding: AstraZeneca.