Semaglutide Slows Kidney Disease Progression in Type 2 Diabetes Patients

Semaglutide — a medication commonly sold as Ozempic or Wegovy — is typically associated with weight loss.

But it can also slow the progression of kidney disease in people with type 2 diabetes and chronic kidney disease.

A new analysis published today found people with type 2 diabetes and chronic kidney disease who took semaglutide once a week had improved kidney function and survival rates, even if they had a history of heart attacks, strokes or heart failure.

It builds on previously published research which found the drug had "consistent benefits" on preventing heart attacks, strokes, and death due to cardiovascular causes in those with type 2 diabetes and chronic kidney disease.

Katherine Tuttle, the lead researcher for the new analysis and professor of medicine at the University of Washington, described semaglutide as a "highly kidney protective therapy".

"While reducing risks of major adverse cardiovascular events is paramount for people with heart disease or high heart disease risk, staying alive without the need for dialysis to sustain life is equally important," she said.

So, how does a drug developed to help people with type 2 diabetes and popularised as a weight-loss therapy help slow the progression of kidney disease?

GLP-1s and kidney disease

Ozempic is part of a class of drugs called GLP-1 receptor agonists, which were originally designed to help people with type 2 diabetes manage blood sugar levels.

These drugs mimic the activity of a natural hormone called glucagon-like peptide 1 (GLP-1).

In recent years, GLP-1 mimicking medicines have gained popularity as weight-loss drugs as they slow digestion and helping people feel full for longer.

James Tang, kidney specialist and transplant physician at St Vincent's Hospital who did not contribute to the study, said there were a few knowns and some unknowns about how semaglutide helped slow kidney disease progression.

Firstly, Dr Tang explained that type 2 diabetes, chronic kidney disease, heart disease and obesity were all interconnected.

Thus, by easing the impact obesity and type 2 diabetes have on the body, there would be a positive "flow on effect" to the kidneys.

"A lot of kidney disease [treatment] is by treating the original cause," he said.

But in terms of the "exact mechanism" of how, or if, semaglutide alone improved kidney health, Dr Tang said more research was needed.

Dr Tang said patients with type 2 diabetes and chronic kidney disease were at high risk for kidney failure, heart issues and premature death.

About 2.7 million Australian adults had biomedical signs of chronic kidney disease, according to the latest estimates, although the condition was typically diagnosed in its advanced stages when symptoms start to show.

Last year, the Therapeutic Goods Administration approved the use of Ozempic to help reducing kidney disease progression for those with type 2 diabetes and chronic kidney disease.

Study limitations and funding source

Professor Tuttle's study used data from the FLOW (Evaluate Renal Function with Semaglutide Once Weekly) trial, which is funded by pharmaceutical company Novo Nordisk.

Novo Nordisk makes Ozempic and Wegovy.

Heart Foundation senior manager for healthcare programs and clinical strategy Natalie Raffoul, who is a registered pharmacist and did not contribute to the study, said this sponsorship wasn't a surprise.

"Almost all of the major clinical trials involving this class of [GLP-1] medicines have been financially sponsored by the pharmaceutical industry," she said.

"This is standard for most medicines."

Ms Raffoul said the conflict had been publicly declared and typically managed "through multiple layers of independent clinical and academic governance steering groups".

Most of the FLOW trial's participants were older, male and white, which Professor Tuttle conceded was a limitation.

"Yes, we would liked to have had more racial and ethnic diversity as well as more women in the study," she said.

"We also wish the study had continued longer in order to have more statistical power for some of the secondary outcomes and subgroup analyses."

Despite these limitations, Ms Raffoul and Dr Tang agreed the analysis was a sound study which contributed further evidence about potential benefit of semaglutide to high-risk populations.

GLP-1s and other health benefits

The Heart Foundation last month released new guidelines to reduce obesity in people with established or high-risk of heart disease.

It recommended semaglutide be considered for weight loss in people with established cardiovascular disease, like history of heart attack, to reduce future risk.

Ms Raffoul described it as a timely move.

"There is more and more emerging evidence that these medicines not only can help manage overweight and obesity, but also help to prevent people from having heart attacks and heart events," she said.

But Ms Raffoul said there were some "million dollar questions" which remained.

One of them, she explained was whether these drugs helped people lose weight and this weight loss was the key driver behind the heart health improvements, or whether the drugs independently improved heart health.

"Weight loss in itself can then have flow on effects, particularly on your cardiovascular risk factors like your blood pressure, like your cholesterol and other things," she said.

Ms Raffoul said there were studies currently underway investigating whether semaglutide had independent "anti-inflammatory effects", which could help improve heart health outcomes.

She noted that Ozempic-like drugs required a prescription and were not without risk or side effects.