Dapagliflozin in Patients with Chronic Kidney Disease
Comprehensive Overview
This study, published in The New England Journal of Medicine (2020), tested whether a medication originally developed for type 2 diabetes could help protect the kidneys and hearts of people with chronic kidney disease, including those who did not have diabetes at all. The drug, dapagliflozin, belongs to a class called SGLT2 inhibitors, which lower blood sugar by helping the kidneys flush excess glucose out through urine, but had also shown early signs of protecting kidney function independent of their blood-sugar-lowering effects. Researchers conducted a randomized, double-blind, placebo-controlled trial, known as DAPA-CKD, enrolling 4,304 adults with reduced kidney function and elevated urine protein levels at over 380 sites in 21 countries, about two-thirds of whom had type 2 diabetes and one-third of whom did not. All participants continued their usual kidney-protective blood pressure medication and were randomly assigned to take either a once-daily dapagliflozin pill or a placebo, with researchers tracking a combination of major kidney function decline, kidney failure, or death from kidney- or heart-related causes. After a median of 2.4 years, the trial was stopped early because an independent monitoring committee determined that dapagliflozin was providing such a clear benefit that continuing the trial would be unethical.
Outcomes and Implications
The most striking finding was that patients taking dapagliflozin were about 39 percent less likely to experience major kidney decline, kidney failure, or death from kidney or cardiovascular causes than those taking a placebo, a benefit large enough that only 19 patients needed treatment to prevent one such serious event. Looking at the outcomes separately, dapagliflozin cut the risk of kidney failure or a severe drop in kidney function by roughly 44 percent, and lowered the risk of death from any cause by about 31 percent. These benefits held up consistently whether or not a patient had type 2 diabetes, meaning the drug worked just as well for kidney protection in people whose kidney disease had nothing to do with diabetes. This matters because, apart from a widely used older class of blood pressure medications, doctors have had very few proven drug options to slow kidney disease progression in patients without diabetes. Dapagliflozin's established safety profile held up in this more vulnerable population with significantly impaired kidney function, and no new safety concerns emerged, including no cases of a rare but serious blood-sugar complication sometimes linked to this drug class. The trial's early stoppage for benefit is itself notable, reflecting how compelling the protective effect appeared partway through the study. The authors conclude that adding dapagliflozin to standard kidney-protective treatment should be considered for a much broader population of chronic kidney disease patients than previously thought, regardless of whether diabetes is present.