Blockbuster weight loss drugs Wegovy and Ozempic are being tested to treat addiction and dementia

LONDON — Scientists have begun investigating whether so-called miracle obesity drugs could be used to treat conditions such as dementia and alcohol addiction after recent trials pointed to the drugs' efficacy in treating serious health issues.

Late-stage trial data released last month by Novo Nordisk indicated that its Wegovy weight loss injection led to "large reductions" in heart failure-related symptoms among at-risk patients.

It comes weeks after the Danish pharmaceutical company published the results of its much anticipated "SELECT" study, which showed the drug's role in reducing the risk of major cardiovascular events such as heart attacks or strokes.

The findings mark a major milestone as the company seeks to broaden perceptions of its product — dubbed by some a "vanity drug" — and researchers are hopeful they spell positive news for the drugs' other applications.

"The results show that this medication can have health benefits above and beyond the short-term," Christian Hendershot, director of the clinical and translational addiction research program at the University of North Carolina at Chapel Hill, told CNBC via Zoom.

Hendershot is one researcher investigating whether the appetite-regulating mechanisms at play in weight loss drugs could be used to treat other conditions such as alcohol and drug addiction.

Novo Nordisk's Wegovy and Eli Lilly's Mounjaro work by imitating a naturally occurring gut hormone that helps regulate appetite in the brain, ultimately leading to weight loss. For that, they rely on active ingredients called semaglutide and liraglutide, respectively, which belong to a group of drugs called GLP-1 receptor agonists.

Pre-clinical trial data has for several years pointed to the efficacy of GLP-1 medication in reducing drug and alcohol intake among animals. Hendershot is now testing Ozempic — Wegovy's predecessor used to treat type 2 diabetes — to see whether those trends apply to humans, too.

"There is reason for optimism, particularly given the reports. Now it's our job to do the research to validate those findings with clinical data," said Hendershot, who expects to publish early findings next year.

If broader applications of the drugs are proven to be effective, the implications could be vast, according to Kyle Simmons, professor of pharmacology and physiology at Oklahoma State University, who cited early indications of the drugs' efficacy in reducing cocaine, amphetamine and opioid cravings.

Simmons is currently leading the Semaglutide Therapy for Alcohol Reduction (STAR) trial, a 12-week double-blind, placebo-controlled study, which is running in tandem with a separate but similar study at the University of Baltimore.

"If those two studies both read out, and they're both positive, it's hard to overstate the effect this will have on the field," he said.

Some researchers are hopeful the drugs could also have use cases in the treatment of dementia and other cognitive disorders.

Already, there is evidence to suggest that GLP-1 drugs can reduce the build-up of amyloid and tau on the brain — two proteins thought to be responsible for Alzheimer's disease, the most common type of dementia.

Now, a trial underway at the University of Oxford will test patients at risk of developing dementia — i.e. those with high levels of amyloid on the brain — to see whether the drugs lead to a reduction in tau accumulation and brain inflammation.

"We want to see if these drugs are interfering with the core Alzheimer's disease pathology," said Ivan Koychev, a senior clinical researcher, who is leading the study.

Elsewhere, others think the drugs could have potential applications in the treatment of polycystic ovary syndrome (PCOS), a disorder that can cause irregular periods, hormone imbalances and fertility issues.

"If women with PCOS exhibit positive outcomes in terms of irregular periods and hirsutism [excess hair growth] despite modest weight loss, it could underscore the medication's broader therapeutic potential," said Harshal Deshmukh, a consultant endocrinologist and senior clinical lecturer at the University of Hull, who is currently conducting one such trial.

Additional possible use cases for weight loss drugs could exacerbate the hurdles already faced by patients using them, however: high costs and supply shortages.

Earlier this month, Novo Nordisk extended restrictions on starter doses of Wegovy due to production constraints, while Eli Lilly warned of continued delays in Mounjaro output for the same reason.

Hendershot said his study was not currently being impacted by shortages, but Simmons described it as a "significant concern."

Meantime, concerns have been raised about the possible adverse effects of the drugs after some patients reported thoughts of suicide or self-harm.

Novo Nordisk CEO Lars Fruergaard Jorgensen told a Reuters Newsmaker event last month that the number of suspected cases remained minimal relative to the wide reach of the drug. "When you have medicine that's used in millions of patients, and many different types of patients, then you can come across different events," he said.

However, Simmons said that more research is still needed to understand the impact of such drugs on reward signaling in the brain. His own research will test for such signals by monitoring participants' reward responses in a virtual reality simulation.

"Is this medication, because of its effects maybe on the mesolimbic dopamine system, just turning down the gain on reward signaling in such a way that could promote anhedonia?" Simmons said. Anhedonia is a term used to describe a reduced ability to experience pleasure.

"If this drug is used by more and more people, if it starts to promote a loss of interest in pleasure more generally, that might not be a great thing, for example, for people who have a history of major depressive disorder," he added.

If you are having suicidal thoughts, contact the Suicide & Crisis Lifeline in the U.S. at 988 or the Samaritans in the U.K. at 116 123.