Ozempic and chronic kidney disease (FLOW)

What the indication says

Section 1 of the Ozempic® label lists three uses in adults with type 2 diabetes: improving blood sugar control alongside diet and exercise, lowering the risk of major cardiovascular events in those with established heart disease, and, in those with chronic kidney disease, lowering the chance of a lasting fall in eGFR, end-stage kidney disease or cardiovascular death ^[1].

The Medication Guide describes the kidney use in plain words as reducing the risk of kidney disease getting worse, kidney failure and death from heart disease. It applies to people with both type 2 diabetes and chronic kidney disease, not to kidney disease on its own, and the guide says it is not known whether Ozempic® is safe and effective in children ^[1].

How the US, EU and Canadian documents word it

Regulators read the same FLOW data but placed it differently in their documents. The table summarises what each one said when we checked on 20 October 2026.

Two kidney tests: eGFR and UACR

• eGFR, the estimated glomerular filtration rate, shows how well the kidneys filter blood. MedlinePlus explains that it is usually calculated from creatinine, a muscle waste product that builds up in the blood when the kidneys are not working well. A lower eGFR means less filtering ^[9].
• MedlinePlus gives rough bands: an eGFR between 60 and 90 may mean early kidney disease, between 15 and 60 may mean kidney disease, and below 15 may mean kidney failure. It lists diabetes, high blood pressure, a family history and age over 60 among the reasons the test is ordered ^[9].
• UACR, the urine albumin-to-creatinine ratio, compares albumin in the urine with creatinine. MedlinePlus notes that healthy kidneys let very little albumin through, so higher amounts can be an early sign of kidney damage ^[10].
• FLOW required both kinds of evidence. People with an eGFR of 50 to 75 needed a UACR above 300 mg/g, and people with an eGFR of 25 to under 50 needed a UACR above 100 mg/g; in both cases the UACR had to be below 5,000 ^[2][3].

Who was in FLOW

FLOW was a randomised, double-blind, placebo-controlled trial in 3,533 adults with type 2 diabetes and chronic kidney disease. Everyone needed an HbA1c of 10% or less at screening and had to be on the highest tolerated labelled dose of an ACE inhibitor or ARB, two common types of blood pressure medicine that act on the renin-angiotensin system, unless they could not take them. Inherited, autoimmune and some congenital kidney diseases were excluded ^[1].

In the label’s description, the average age was 67 and 70% were men. Average eGFR at the start was 47, and 11% had an eGFR below 30. The median UACR was 568 mg/g, and 69% were above 300. At baseline, 95% took an ACE inhibitor or ARB, 16% an SGLT2 inhibitor, 76% a statin and 50% an antiplatelet medicine ^[1]. The EU product information adds that participants had lived with diabetes for 17.4 years on average and had a mean BMI of 32 ^[3].

What the trial measured

Participants received semaglutide 1 mg once weekly or placebo on top of their usual care. The main outcome combined several serious events: a lasting fall in eGFR of at least 50%, a lasting eGFR below 15, starting long-term dialysis or a transplant, or death from kidney or cardiovascular causes. “Lasting” meant two measurements at least 28 days apart ^[1].

The trial was stopped early for efficacy after a planned interim analysis, on the advice of its independent data monitoring committee ^[3]. The published summary reports a median follow-up of 3.4 years, the label gives 41 months and the EU text 40.9 months; these are the same follow-up described in different units ^[1][2][3].

The results, line by line

The label’s Table 10 lists the main outcome and each of its parts. Placebo comes first, then Ozempic® 1 mg, then the hazard ratio, which compares how often first events happened in each group over time; values below 1 favour semaglutide ^[1].

Reading the table

Three of the kidney rows have confidence intervals that cross 1, so the trial on its own cannot show a difference in those single parts; the label instead says the overall effect reflected fewer large eGFR falls, progression to kidney failure and cardiovascular deaths ^[1]. The summary adds that the kidney-only parts of the main outcome, taken together, gave a hazard ratio of 0.79 (0.66 to 0.94) ^[2].

Kidney function also declined more slowly: the yearly eGFR slope was less steep by 1.16 mL/min/1.73 m² with semaglutide. Serious adverse events of any kind were reported in 49.6% on semaglutide and 53.8% on placebo ^[2]. By week 104, body weight had fallen by 5.6 kg on semaglutide and 1.4 kg on placebo ^[3].

Details the label adds

The label says the benefit was broadly consistent across age, sex, eGFR and UACR groups, but was not evident in people already taking an SGLT2 inhibitor at baseline, where there were few events. It also notes that renal deaths were few, and section 12.1 states that how semaglutide lowers kidney-related risk has not been established ^[1]. The Canadian monograph suggests the effect is probably multifactorial, partly through blood sugar, blood pressure, lipids and inflammation, while direct kidney effects remain unproven ^[4].

For this use, the dosing section describes a maintenance dose of 1 mg weekly, reached once 0.5 mg has been taken for 4 weeks or longer, after the usual starting step. The US label also says no dose adjustment is recommended for kidney impairment, because semaglutide levels did not change in a clinically relevant way, and the EU text adds that experience in end-stage kidney disease is limited ^[1][3]. Your dose is your prescriber’s decision.

Safety data collection in FLOW was limited to serious adverse events and some predefined categories, and the label reports that no new serious or severe adverse reactions were identified ^[1].

The kidney warning in the same label

The same label warns about acute kidney injury after fluid loss. Section 5.6 describes postmarketing reports, some needing dialysis, mostly in people whose nausea, vomiting or diarrhoea led to dehydration, and asks prescribers to check kidney function in people with such symptoms, especially when starting or raising the dose ^[1].

The Medication Guide asks you to drink fluids to lower the chance of dehydration and to let your healthcare provider know quickly when nausea, vomiting or diarrhoea keeps going ^[1]. A kidney benefit over years and a short-term risk during dehydration can both be true. Our separate article on Ozempic® and dehydration covers that warning in detail.

Without diabetes, and other semaglutide products

Neither the Ozempic® nor the Wegovy® US label lists a kidney indication for people without type 2 diabetes ^[1][8]. A prespecified kidney analysis of the SELECT heart trial, in adults with overweight or obesity and cardiovascular disease but no diabetes, reported a composite kidney endpoint in 1.8% on semaglutide 2.4 mg and 2.2% on placebo, a hazard ratio of 0.78 (0.63 to 0.96) ^[11]. That is a secondary analysis of a trial designed for heart outcomes, not an approved use.

Rybelsus® and Ozempic® tablets were tested in their own outcome trial, SOUL, which included people with chronic kidney disease. The EU product information reports a hazard ratio of 0.91 (0.80 to 1.05) for its composite kidney outcome, and the published summary says the confirmatory secondary outcomes did not differ significantly from placebo ^[6][7]. The kidney evidence on this page therefore applies to Ozempic® injection 1 mg, the product used in FLOW.

Ozempic®, Wegovy® and Rybelsus® are registered trademarks of Novo Nordisk A/S. PepLabo is not affiliated with or endorsed by Novo Nordisk.