Only about 15% of people who began taking GLP-1 drugs such as Wegovy stuck with them after two years, according to a new analysis by pharmacy benefit manager Prime Therapeutics.
The findings could make the case for insurers and employers to cover the drugs even tougher. Less than half of companies cover workers’ GLP-1 drugs for weight loss, by some estimates, and some employers have cited problems with adherence as a reason. The drugs have proven to help people lose significant amounts of weight and prevent heart problems, but studies have found that people regain most of it when they stop medication.
Pat GleasonResearchers at Prime, which is owned by a group of Blue Cross Blue Shield plans, didn’t dig into why patients quit the drugs. Pat Gleason, Prime’s assistant vice president of health outcomes who led the study, said in an interview with Endpoints News that there could be a number of reasons, ranging from benefit changes that raised costs to supply shortages and side effects.
Patients also might have stopped taking the drugs because they met their goal weight, he said, or they might have switched to a compounded drug, which wouldn’t show up in a pharmacy claim. He said it’s less likely that the patients studied lost insurance for their weight loss drugs, though, because Blue’s plans tended to continue covering GLP-1s for patients already on them.
Gleason said the findings spotlight the disconnect between clinical trials and the real world. For example, 77% of patients in a major clinical trial for semaglutide were still taking the target dose 2 years later. He said the real-world data underscore the need for health plans to make sure patients get the comprehensive care, like case management and behavior modification programs, that patients got in some trials.
“If people don’t stay on therapy, that’s waste,” he said.
Prime analyzed insurance claims for roughly 3,400 patients who had started taking a GLP-1 in 2021, were continuously enrolled in commercial insurance, and were diagnosed with obesity or had a body mass index of greater than 30. Patients with diabetes were excluded.
The analysis found that an increasing number of patients quit taking their drugs as time went on. Only about 47% of patients were still taking a GLP-1 at 180 days, 29% at one year, and 14.8% at two years.
Patients taking drugs that are injected weekly, such as Wegovy and Ozempic, stuck with them for longer. About a fourth of patients using Wegovy were still taking it at the two-year mark, and 22% were still taking its sister drug Ozempic. Ozempic, approved to treat type 2 diabetes, contains the same active ingredient as obesity drug Wegovy and is often prescribed off-label for weight loss.
Meanwhile, just 7% of patients taking drugs injected daily, including obesity drug Saxenda and diabetes drug Victoza, were taking them after two years. Like Ozempic, Victoza can be prescribed off label for weight loss.
Novo Nordisk, which makes all of the drugs included in the study, said in a statement that it “does not believe these data are sufficient to draw conclusions about overall patient adherence and persistence to various GLP-1 medicines, including our treatments.”
A company spokesperson said Prime’s analysis had several limitations, including that the PBM didn’t cover Wegovy until 2022. But Gleason said self-insured employers still were able to cover Wegovy, even if it wasn’t on Prime’s formulary.