Effective weight loss achieved even with inconsistent GLP-1 access

Popular anti-obesity medications continue to be effective for weight loss even when availability and access is interrupted, according to a study being presented by a private weight-loss company Monday at ENDO 2025, the Endocrine Society's annual meeting in San Francisco, Calif.

"Patients taking GLP-1 treatments like semaglutide and tirzepatide often face challenges consistently accessing their medications due to supply shortages or insurance coverage obstacles," said Kaelen L. Medeiros, M.S., director of data and research at privately held weight-loss company Calibrate in New York, N.Y.

While unpredictable GLP-1 medication access is frustrating, the good news is that our research shows effective weight loss can still be achieved if paired with appropriate lifestyle changes and coaching support."

Kaelen L. Medeiros, Director, Data and Research, Calibrate

Researchers looked at how interruptions to GLP-1 medication access impacted weight-loss outcomes in real-world patients taking part in a commercial metabolic health program that also included intensive lifestyle intervention. Participants followed an intensive lifestyle change curriculum that emphasized the four pillars of metabolic health: food, exercise, sleep and emotional health, while receiving one-on-one health coaching.

The study reviewed records for 6,392 participants who had at least one month of GLP-1 access and completed at least one year in an obesity and overweight care program. Of these participants, 72.5% experienced at least one disruption in their GLP-1 treatment and 11.1% had multiple disruptions. Participants received an average of 8.13 GLP-1 fills during the first year of research and 15.25 fills during the second year.

After 12 months, participants who faced access issues achieved 13.7% weight loss in 12 months and 14.9% in 24 months. Those without treatment interruptions had 17% weight loss in 12 months and 20.1% in 24 months. Those who received only 1 to 4 treatments over 12 months also achieved clinically significant weight loss, with more than 10% change in body weight on average.

"Given the often-unpredictable availability and shifting insurance coverage associated with anti-obesity medications, it's important that patients understand the significant impact that lifestyle changes and coaching paired with treatment can have on their health outcomes," Medeiros said.

While findings indicate that significant weight loss is still possible for those with inconsistent access to GLP-1 medications, Medeiros said the results found that a consistent medication course combined with lifestyle changes and support remains the most effective weight-loss program option.