A New Test Predicts Who Will Benefit Most From Weight Loss Drugs

AAs popular as the new group of weight loss medications like Wegovy and Zepbound are, not everyone responds to them the same way.

In a new presentation at Digestive Disease Week conference in Washington, Mayo Clinic associate professor of medicine Dr. Andres Acosta reported that a genetic test he developed can identify which people are most likely to respond to semaglutide (Wegovy) and which are not.

The test, called MyPhenome, from a company Acosta co-founded called Phenomix, relies on a combination of genetic and other factors to categorize people into different types of weight gain. Acosta identified about two dozen genes linked to obesity and more than 6,000 variants of those genes, to classify people who struggle with weight gain into four categories:

In his latest presentation (the results of which have not yet been published in a journal), Acosta reports that the MyPhenome Hungry Gut test predicts with 75% accuracy who will respond to semaglutide.

“This has huge implications – first for the patient, because there is no more trial and error, and second, as a doctor, I want to know which of my patients will respond, because I’m asking them to spend $1,000 a month or pay a high copay if your insurance covers the medications,” he says. Having a better idea about whether a person will respond to drugs like Wegovy could also alleviate access issues by targeting only the best candidates for it. “This could change the way we manage obesity,” he says.

see more information: Is Ozempic the new anti-inflammatory miracle drug?

The study involved a small number of patients – 84 people who were overweight or obese, only a few of whom had diabetes – who provided a saliva sample for the MyPhenome test for genetic analysis and also answered a questionnaire about their eating habits. Each took semaglutide for a year and most reached the maximum dose. Because the Hungry Gut profile involves appetite and semaglutide works by suppressing the desire to eat, Acosta found that people who fall into this category were more likely to lose more weight with semaglutide. In the study, 51 of the 84, or about 60%, were classified as Hungry Gut.

“Patients with Hungry Gut lost 19.5% of their body mass after one year, compared to 10% of those who had negative Hungry Gut,” says Acosta. “That’s almost double the weight loss. For the first time, we can identify the best responders.”

Acosta and his team say larger studies that replicate these initial findings need to be completed before the test can be used more widely. For now, doctors can order the MyPhenome test for patients on the Phenomix website and use it as additional information to help them and their patients decide whether the medicine is suitable.

“My dream is to treat chronic diseases like obesity in the same way we treat cancer – with great precision,” says Acosta about the next steps of the test. It’s also possible that as more next-generation weight-loss drugs are approved, pharmaceutical companies will simultaneously develop screening tests to identify the people most likely to benefit from their drugs. Insurers can also begin to rely on these tests when making reimbursement decisions to ensure patients are receiving the treatments that are right for them.

Acosta says the test’s potential is not limited to semaglutide. For some people, some of the older weight loss medications may be just as effective, but until now, doctors have relied on a trial-and-error method to prescribe them. With more precise ways to match patients to the medications that work for them, all existing weight loss medications could be better optimized for the right patients.