Kidney biopsies show semaglutide may help damaged tissue repair itself

A Nature Medicine analysis of 106 patients finds semaglutide linked to less scarring and inflammation in kidney tissue. Reversal itself remains untested.

A study published in Nature Medicine on October 1 looked inside the kidneys of people taking semaglutide, the active ingredient in Ozempic. The lead author is Katherine Tuttle, a nephrologist at the University of Washington's Providence Medical Research Center in Spokane. The work covered 106 participants, all with type 2 diabetes and chronic kidney disease.

The participants came from an earlier trial, reported in the New England Journal of Medicine in 2024. That trial found semaglutide lowered the likelihood of kidney failure, heart attack or stroke death compared with placebo. It was stopped early because the benefit was so large that continuing placebo was judged unethical. The new analysis compared kidney tissue samples taken before and after semaglutide with samples from placebo recipients.

Semaglutide treatment was linked to more blood flow, less scarring and lower blood vessel stiffness in kidney tissue. Urine albumin dropped in treated patients and changed little on placebo, which points to less leaky kidney filters. In glomerular cells, genes tied to metabolic stress and inflammation were turned off and repair genes were turned on. Signals between blood vessel cells and immune cells suggested the immune cells quieted down.

This matters because chronic kidney disease affects an estimated 674 million people worldwide, and diabetes and high blood pressure are among the most common causes. If an already widely used drug can do more than slow decline and actually support repair, treatment for a very large group of patients could rest on something that exists today.

The caveats are real. The sample is small and limited to people with type 2 diabetes and chronic kidney disease. The study shows signs of repair at tissue and gene level. It did not test whether kidney disease is reversed or whether dialysis is avoided. Susan Quaggin of Northwestern, who was not involved, said the findings suggest rather than prove a direct protective effect on kidney blood vessels.

Source: Science News