Many people using GLP-1s for weight loss stop treatment too soon, research shows, and results are not one-size-fits-all

Demand for Wegovy and other GLP-1 drugs used to treat obesity and diabetes has skyrocketed, but a new report suggests that many people may not be sticking with their weight-loss treatment long enough.

An analysis of health insurance claims released Tuesday found that most people using GLP-1 medications – about 58% – were on their treatment plan for less than 12 weeks, falling short of a key benchmark in the weight-loss treatment timeline. Professional organizations have set this as a guideline for when to reassess whether a treatment is providing clinically meaningful weight loss.

Users start with a low dose of these medications and gradually increase it over time until they reach a targeted dose. But the analysis shows that nearly a third of people – more than 30% – dropped out after the first four weeks of treatment, before reaching the targeted dose.

The findings are based on pharmacy and medical claims data for about 170,000 people with insurance coverage under Blue Cross Blue Shield plans who were prescribed GLP-1 medications that were approved to treat weight management between 2014 and 2023.

“These are long-term medications to treat a chronic disease,” said Dr. Disha Narang, an endocrinologist and director of obesity medicine at Endeavor Health in Chicago, who was not involved in the new research. “This is absolutely a marathon, not a sprint. And when we do treat this as a sprint, I think patients are likely to get off of medication much faster.”

Experts say that impatience with results is one of many reasons patients might stop treatment. Only about two-thirds of adults who have used injectable weight-loss drugs say they feel that they were effective, according to a new KFF poll. And people who stopped using the medications were significantly less optimistic about their benefits: Only about half of those who had used injectable weight-loss drugs in the past said they were effective, compared with nearly three-quarters of those who were actively using the treatments.

Side effects – such as nausea, diarrhea, vomiting and constipation that are common early on – may also drive people away. Data from the longest clinical trial of Wegovy showed that 17% of people using the drug decided to stop participating in the trial because of side effects.

But experts say that many deterrents can be managed with appropriate counseling from a provider.

“If you don’t have frequent touchpoints, frequent interactions, then it’s really it’s hard to manage side effects. It’s hard to manage expectations. It’s hard to see if there’s improvement in some of these other metabolic comorbidities,” said Dr. Jody Dushay, an endocrinologist at Beth Israel Deaconess Medical Center and assistant professor of medicine at Harvard Medical School who was not involved in the new research.

Each person will respond to treatment differently and assess the balance of costs and benefits to their heath differently.

“There’s not a line in the sand for every single person. Physicians and patients have to just look at all the data and make a decision about treatment together,” she said.

Findings from the Blue Cross Blue Shield data emphasize the important role that providers can play in helping patients stick with their treatment with GLP-1s.

People who met with their providers less frequently – and those living in underserved regions with broader health inequities – were more likely to discontinue GLP-1 treatment sooner. Each additional follow-up visit increased a patient’s chances of staying on the treatment by 60%, said Dr. Razia Hashmi, vice president of clinical affairs for the Blue Cross Blue Shield Association.

And although most prescriptions came from primary care physicians, those who were prescribed GLP-1s by endocrinologists or others with expertise in weight management were more likely to reach at least 12 weeks of continuous treatment.

“Wraparound support services really make a difference – whether a person has lifestyle support management, nutrition, diet and side effect management,” Hashmi said, and “health equity matters. Social drivers of health – transportation, access to food, socioeconomic status – all of that also makes a difference.”

Cost can often be a prohibitive factor for these medications – a month’s supply of GLP-1 medications can often cost about $1,000 – but the analysis included only people who had insurance plans that covered weight-loss medication prescriptions. Insurance plan copays may have affected cost considerations, but the individuals in this analysis were not paying out-of-pocket for their treatment.

But using GLP-1 treatments are still an investment in many ways.

“Whether it’s an employer trying to make a decision or an individual patient trying to make a decision, it’s really important to understand the success factors,” Hashmi said. “We want the investment to pay off.”

Another new report supports the claim that the benefits of GLP-1s are extended with long-term, consistent treatment.

One of the first reports offering real-world data on GLP-1 efficacy found that people using the medicines had lost an average of about 1.4% of their starting body weight after three months, which steadily increased to an average of about 3% weight loss after a full year on the treatment. The analysis from Dandelion Health, a health care analytics firm, is based on the electronic health records of nearly 17,000 people who were prescribed a GLP-1 from 2019 through 2023.

Compared with a group of people with a similar set of clinical characteristics – matched closely on demographic factors such as age and ethnicity, treatment indicators such as average body mass index and diabetes prevalence, history of treatments such as bariatric surgery and prevalence of related comorbidities – the analysis found that those on GLP-1s lost about twice as much weight.

These injected medications, called GLP-1 agonists, are in high demand because they have proved to be so effective for weight loss. In clinical trials, some of the stronger medications like Wegovy and Zepbound have been found to help people lose at least 10% of their starting weight. But the new report suggests that the real-world efficacy is not as promising as clinical trial data would suggest.

And experts warn that the GLP-1 treatment process can be different for everyone.

“There are some people who are under-responders, there are some people who are over-responders, and there’s some that respond as expected to the medication,” Narang said. “Studies are still happening to understand why.”

The data from Dandelion Health showed that the 10% of people with the best response to GLP-1s had results that mirrored what clinical trials found, but the 10% with the least success with the treatments had no weight change, or even an increase in weight, over time.

Still, GLP-1 medications may have benefits far beyond weight loss – for heart and liver health, for example – which may extend even to people who don’t lose as many pounds as they might have expected, experts say.

“It’s really important to not use the scale as the only outcome of whether you should stay on this medication. People might be making slow but steady progress, which could warrant ongoing treatment,” Dushay said. “There may be some direct benefits of the medication in the absence of significant weight loss, which is also why you should be talking to your doctor at length about why you’re using this medication.”

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