The study included 4,401 patients, aged 30 and older, with type 2 diabetes and chronic kidney disease. These patients were randomly assigned to 690 sites in 34 countries to take canagliflozin or a placebo, from March 2014 to May 2017.
They were followed at 3, 13 and 26 weeks, during which the effects of the drug were monitored.
The researchers found that in the canagliflozin group the relative risk of death from renal causes was 34% lower and the relative risk of end-stage renal disease was 32% lower. The group also had a lower risk of cardiovascular death, heart attack, stroke and hospitalization for heart failure.
Based on the study's data, the researchers estimated that treatment with canagliflozin would have prevented 22 hospitalizations for heart failure and 25 composite events of cardiovascular death, heart attack or stroke among 1,000 patients.
The study had some limitations, including the fact that it did not include patients with very advanced kidney disease. Nor did it include patients whose kidney disease was thought to be due to conditions other than type 2 diabetes. Further research is needed to determine whether the results of the study could be generalized to other types of kidney disease.
"With this whole class of drugs, we really need to think about how we use it because of the heart benefits and kidney benefits," Molitch said about SGLT2 inhibitors.
"This class of drugs really has its primary action on the kidney, from the point of view of diabetes, so normally we have a lot of glucose – the main sugar that circulates in the blood – and then the kidney filters glucose. Time has no glucose in the urine because the kidney reabsorbs all the glucose that is filtered by the blood, "he said. "What these drugs do is that they block the reabsorption of glucose into the blood from the urine and then excrete a lot of glucose in the urine."
"We are not yet sure what the mechanisms that cause these benefits to the heart and kidneys are, but they are clearly not just due to the lowering of blood sugar level," he said.
"Cardiac and renal benefits occur in patients with more advanced kidney disease, where the hypoglycemic effects of canagliflozin would be minimal," he said. "So, based on this study, we could use canagliflozin only for kidney benefits and possibly heart benefits while using other drugs to control glucose levels in patients with diabetes and kidney disease."
"This study was designed to include individuals with diabetic kidney disease and, as such, is the first example of reducing the risk of renal failure [as] and improving cardiovascular outcomes," said Leroith, who was not involved in the study . "I believe the document is extremely significant and will have a very educated public with important implications."