Novo Nordisk has announced that an older version of its weight-loss drug, semaglutide, failed to meet its main goal in late-stage trials investigating its ability to slow cognitive decline in Alzheimer’s patients.
The result is a setback for hopes that Alzheimer’s could open a major new market for GLP-1 medicines such as semaglutide, particularly as Novo faces rising competition to its blockbuster drugs in core obesity and diabetes treatments.
The drug in question was Rybelsus, a pill approved only for type 2 diabetes, which, like Novo’s Ozempic and Wegovy, contains semaglutide.
Here are some of the other conditions the drugs are being used and tested for:
Alcohol addiction
A study conducted by the University of Copenhagen’s Psychiatric Centre Rigshospitalet is investigating whether semaglutide – the main ingredient in Wegovy and Ozempic – can help reduce alcohol intake in 108 patients diagnosed with alcohol use disorder and obesity.
Alzheimer’s disease
Novo Nordisk said an older version of semaglutide, branded Rybelsus, failed to slow cognitive decline in early-stage Alzheimer’s patients in two trials, covering a combined 3,808 patients.
Cardiovascular disease
Eli Lilly was testing tirzepatide – the main ingredient in Mounjaro and Zepbound – for patients with heart failure and obesity. Lilly had said it would enroll about 700 people in the study, but the company said in May that it has withdrawn its U.S. application for heart failure approval.
Novo won the U.S. Food and Drug Administration’s approval in 2024 to use Wegovy to reduce the risk of cardiovascular death, heart attack and stroke in overweight or obese adults without diabetes.
The European Medicines Agency backed the use of Novo’s semaglutide to help ease heart failure symptoms in people with obesity in September 2024.
Chronic kidney disease
Novo’s Ozempic is approved in the United States for reducing the risk of kidney failure and disease progression as well as the risk of death due to heart problems in diabetes patients with chronic kidney disease.
Lilly’s tirzepatide is being evaluated in a mid-stage study of patients with chronic kidney disease and obesity. Lilly plans to enroll up to 140 participants with the study expected to be completed next year.
Liver disease
Novo’s Wegovy in August became the first GLP-1 therapy approved in the U.S. to treat adults with metabolic dysfunction-associated steatohepatitis, or MASH, based on results from the first part of its late-stage trial. Results from the second part, with about 1,200 patients, is expected in 2029.
Lilly’s tirzepatidein February helped up to 74 per cent of patients achieve absence of MASH with no worsening of liver scarring at 52 weeks, compared with 13 per cent of patients on placebo, in a mid-stage trial.
Neurological disorders
Researchers at the Danish Headache Center are testing semaglutide along with a very low calorie diet as a treatment for new-onset idiopathic intracranial hypertension, a condition associated with obesity in which blood pressure inside the head rises. The study has enrolled about 50 patients and is expected to complete in October 2025.
Sleep apnea
Zepbound was approved by the U.S. Food and Drug Administration for obstructive sleep apnea in December 2024, making it the first drug to directly treat patients with the common disorder that causes breathing disruption while sleeping.
