Wegovy and kidney health: the semaglutide FLOW study explained

Wegovy (semaglutide) is an injectable weight loss medication that was approved in the UK in 2021.¹ It's clinically proven to be safe and effective, with patients losing an average of 15% of their starting weight after 68 weeks.²

However, weight loss isn't the only benefit. The UK's drug authority has already approved Wegovy as a treatment for serious heart problems.³ And research is being conducted to learn more about the drug's potential for heart, liver and kidney health.

One such study was the FLOW trial. Published in May 2024, this study explored whether Wegovy could help protect the kidneys and heart in people living with type 2 diabetes and chronic kidney disease.

Let's look at the study in more detail.

The Wegovy FLOW study explained

The trial design⁴

A total of 3,533 people took part in the trial, receiving either semaglutide or a placebo (a harmless dummy drug) for up to five years. In both groups, participants administered injections once weekly.

To make sure the study was truly representative, researchers established certain inclusion criteria – essentially, a checklist a person must meet to be considered eligible.

The main conditions were:

• They had to have a diagnosis of chronic kidney disease (CKD). This is defined by medical measurements like eGFR (how well the kidneys filter blood) and UACR (how much protein is in the urine)
• They had to have a medical diagnosis of type 2 diabetes.
  
  

What the trial looked at

The FLOW trial sought to learn whether semaglutide reduced the risk of serious kidney failure or death related to kidney or heart disease.⁴

There's a reason the researchers looked at heart health, as well as the drug's benefits for CKD. People can potentially become very ill because of heart problems before progression to end-stage kidney disease.

So, if semaglutide can potentially reduce the risk of heart problems, that would be very good news for people living with CKD.

Results from the FLOW study 

The main things the study looked at (its primary outcomes) were:

• Serious kidney failure
• Death related to kidney or heart disease
  
  

The study found that people in the semaglutide group saw a dramatically lower risk of these issues.

Breaking the results down, researchers saw:

• A 24% lower risk of serious kidney failure or death caused by kidney or heart disease
• A 21% lower risk of kidney-specific conditions (such as failure or the need for a transplant)
• A 19% lower risk of heart-specific conditions
• An 18% lower risk of major cardiovascular events (such as a heart attack)
• 20% lower risk of death by any cause
  
  

What the results show us

In short, the treatment group taking semaglutide were less likely to die or develop serious kidney or heart problems compared to those taking a placebo.

This provides compelling evidence to support semaglutide's use as a treatment for those living with chronic kidney disease and obesity. Whether the drug gains approval for this use remains to be seen.

What the trial didn't show, however, was exactly how semaglutide protects the kidneys. Or, in medical terms, it demonstrated a clinical benefit – not a mechanism. More research is needed to understand exactly what's happening in the body to bring about this benefit.

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Sources

1. Novo Nordisk (2021) Wegovy™ recommended for approval for the treatment of obesity by the European regulatory authorities [press release]. Retrieved from https://ml-eu.globenewswire.com/Resource/Download/360b666a-28f8-45b6-855e-052fe0206cef 

2. Wilding, J.P.H. et al. (2021) "Once-Weekly Semaglutide in Adults with Overweight or Obesity" The New England Journal of Medicine, 384(11) https://doi.org/10.1056/NEJMoa2032183

3. Medicines and Healthcare products Regulatory Agency (2024)  MHRA approves GLP –1 receptor agonist semaglutide to reduce risk of serious heart problems in obese or overweight adults [press release]. Retrieved from

https://www.gov.uk/government/news/mhra-approves-glp-1-receptor-agonist-semaglutide-to-reduce-risk-of-serious-heart-problems-in-obese-or-overweight-adults

4. Perkovic, V. et al. (2024) "Effects of Semaglutide on Chronic Kidney Disease in Patients with Type 2 Diabetes" The New England Journal of Medicine, 391(2) https://doi.org/10.1056/NEJMoa2403347

This article was reviewed and approved by Lujain Alhassan, Bariatric Dietitian, and Sarah Abdula, Specialist Dietitian, on 5 January 2026.