Novo’s Wegovy Has Highest Adherence Rates in New Study of Weight-Loss Drugs

Novo Nordisk_iStock, hapabapa

Pictured: Novo Nordisk office/iStock, hapabapa

A study published Wednesday suggests that more people are getting on and staying on one of pharma’s hottest drugs. One year after filling their first prescription, 40% of patients on Novo Nordisk’s Wegovy (semaglutide) were still taking it. That’s more than three times the adherence rate of older obesity medicines. 

The cohort study, published in the journal Obesity, utilized electronic health records and insurance claims data for adults with a BMI ≥30 kg/m2 from Ohio and Florida who had a prescription filled for an anti-obesity medication (AOM) between 2015 and 2022. Across all categories of AOMs, only 19% of the 1,911 patients included in the study were still taking the drugs at 12 months. 

In contrast to the 40% who stayed on Wegovy, only 13% of patients on Orexigen Therapeutics’ Contrave—a combination of antidepressant buproprion and addiction treatment drug nafltrexone—were still filling their prescriptions after a year. Even less patients continued taking Qsymia, Vivus’ combination drug for weight loss. No patients were continuing to take Orlistat by the 12-month mark.  

The study found that greater weight loss results at six months appeared to be directly associated with persistence at one year. Patients are more likely to stay on Wegovy because it tends to work better for most people. Adherence rates also varied depending on insurance carrier among those on private insurance. 

Obesity is a chronic condition, so to maintain benefit patients usually need to stay on the treatments indefinitely. An op-ed also published Wednesday in Obesity concludes that behavioral approaches do not produce lasting weight loss for most patients, as they do not address the physiology or external environment.

The authors of the piece contend that AOMs coming to the market are “game changers” for treating obesity and that behavioral approaches “are complementary and must coexist if we are to make a significant, population-level impact on the obesity epidemic.” 

Novo Nordisk’s GLP-1 agonist has skyrocketed in popularity. Third-quarter 2023 sales logged over 700% growth, with a total around $3.1 billion in revenue for the first nine months of 2023.  

Wegovy isn’t the only game changer on the market. Last month, the FDA approved Eli Lilly’s tirzepatide for weight loss management. Marketed as Zepbound, a real-world analysis showed that Lilly’s tirzepatide beat Novo’s Wegovy for weight loss. Patients receiving Mounjaro, Lilly’s injectable type 2 diabetes drug with the same tirzepatide active ingredient as Zepbound, were three times as likely to drop 15% of their bodyweight than those on Ozempic. Weight loss was also faster on Mounjaro. 

Last week, Pfizer announced it was discontinuing development of its twice-daily weigh loss pill candidate after patients in a mid-stage study had trouble tolerating the side effects. Discontinuation rates were over 50% across all dosage forms.  

Nonetheless, the pharma giant is still moving forward with its pharmacokinetic study of a once-daily version of the drug, danuglipron, in the first half of 2024. The outcome of that study “will inform a path forward,” according to Pfizer’s announcement. 

Kate Goodwin is a freelance life science writer based in Des Moines, Iowa. She can be reached at and on LinkedIn.

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