Research Highlights:
- In two, separate, year-long clinical trials, adults with moderate-to-severe sleep apnea and excess weight (BMI ≥27 kg/m²) who took the oral GLP-1 medication orforglipron, had about 18 fewer breathing interruptions per hour of sleep after 52 weeks, compared with about 5 fewer breathing interruptions per hour of sleep among people who took a placebo, respectively.
- Participants taking orforglipron also had greater reductions in cardiovascular risk factors, including body weight, high-sensitivity C-reactive protein (hs-CRP), a blood marker of inflammation, and systolic blood pressure after one year.
- The ATTAIN-OSA trial included two studies: Study 1 included adults who did not use continuous positive airway pressure (CPAP) therapy, and Study 2 included adults who did use CPAP. Results were broadly similar in both groups, researchers said.
- Note: This trial is simultaneously published today as a full manuscript in the peer-reviewed scientific journal JAMA.
This news release contains updated information provided by the researchers and not listed in the abstract.
CHICAGO, Nov. 9, 2026 — Adults with moderate-to-severe sleep apnea and excess weight had significantly fewer episodes of breathing interruptions while sleeping after taking the daily oral GLP-1 medication orforglipron for one year, compared with adults in the placebo group, according to new, independent, preliminary late-breaking science presented today at the American Heart Association's Scientific Sessions 2026. The meeting on Nov. 6-9 in Chicago is a premier global exchange of the latest scientific advancements, research and evidence-based clinical practice updates in cardiovascular science.
After one year, in addition to improvements in sleep apnea severity, participants taking orforglipron experienced significant improvements in sleep-apnea related drops in blood oxygen levels, body weight, inflammatory markers and blood pressure, and reported better sleep.
"If approved to treat obstructive sleep apnea, orforglipron could be a promising oral pharmacologic option for people with overweight or obesity and this condition. A convenient daily pill may help expand access to treatment for sleep apnea, and it could potentially be used with CPAP or other therapies to better meet individual patient's needs," said the study's presenting author Vaishnavi Kundel, M.D., M.Sc., an associate professor of medicine and program director of the Sleep Fellowship at the Icahn School of Medicine at Mount Sinai in New York City. "Fewer interruptions in breathing during the night may allow for more restful sleep, and waking up more refreshed and having more energy through the day could help improve quality of life."
Researchers say these are the first large trials of an oral medication for obstructive sleep apnea in people with overweight or obesity. They also noted that study participants' weight loss likely contributed to the improvements in sleep apnea severity and other cardiometabolic measures. Future studies are needed to explore if other potential mechanisms beyond weight loss contributed to the benefits found in people taking orforglipron or other GLP-1 medications.
What are the study's key findings?
- Breathing interruptions during sleep decreased by about 18 events per hour among participants taking orforglipron, compared with about 5 events per hour among participants taking a placebo. Results were broadly similar for both CPAP users and non-CPAP users.
- Treatment with orforglipron led to greater reductions in sleep apnea-related drops in blood oxygen levels compared with placebo in both studies (-51% vs.- 18% in Study 1 and -44% vs. -18% in Study 2, respectively).
- At one year, body weight decreased by about 10-11% among participants in the groups taking orforglipron compared with only 1-2% in the placebo groups, respectively.
- Blood tests showed a larger reduction in the inflammation marker high-sensitivity C-reactive protein (hs-CRP) among people in the orforglipron group vs. the placebo group (-42% vs. -4% for Study 1 and -38% vs. -18% for Study 2, respectively).
- Participants taking orforglipron also had larger reductions in systolic blood pressure than those receiving placebo: about -7.5 vs. -1.7 mm Hg in Study 1, and -7.0 vs. -2.2 mm Hg in Study 2.
- The most common side effects were nausea, diarrhea and constipation and were self-reported by participants as mostly mild to moderate.
"Untreated moderate to severe sleep apnea frequently goes hand in hand with high blood pressure, which can strain the heart and blood vessels over time, leading to increased risk of heart disease and stroke," Kundel said. "Even a modest decrease in blood pressure can help protect a patient's heart and overall health. Previous research has confirmed that using CPAP devices while sleeping can help lower blood pressure by about two to three points. In these studies, blood pressure fell by about seven points after one year of taking this oral GLP-1 medication. That's a meaningful blood pressure change that would have a positive impact on cardiovascular health for people with sleep apnea."
Researchers emphasized that this medication is not meant to replace CPAP therapy. Instead, it expands the range of available treatment options for obstructive sleep apnea. The study's results indicate that orforglipron can be used alongside therapies like CPAP, or possibly among patients who are unable to use or choose not to use a CPAP device.
Obstructive sleep apnea occurs when the upper airway repeatedly narrows or closes during sleep. The condition, which affects an estimated 1 billion adults worldwide, interrupts breathing, lowers oxygen levels and disrupts sleep. A continuous positive airway pressure (CPAP) machine is a device used to treat sleep apnea. It delivers a steady flow of air through a mask worn during sleep to keep the airway open and prevent pauses in breathing.
Obesity, defined as a BMI of 30 kg/m² or higher, is a significant risk factor for sleep apnea, according to a 2021 American Heart Association scientific statement on obstructive sleep apnea and cardiovascular disease. In 2022, the Association added healthy sleep to Life's Essential 8, a list of health metrics and behaviors that are essential for ideal heart and brain health.
What are the study's details, background, design and limitations?
- The two ATTAIN-OSA trials included a total of 712 adults with moderate to severe sleep apnea and a body mass index of 27 kg/m² or higher (overweight or obesity), and who did not have Type 1 or Type 2 diabetes. The average age was about 50 years, and about 30% of participants were women. Participants were racially diverse: about 69% of the participants self-identified as white, 18% as Asian, and the remainder self-identified as either Black/African American, Native American, multiple races or other. About 43% of participants identified as Hispanic or Latino ethnicity.
- The first study included 363 participants who did not use CPAP therapy. In the second study, 349 participants were current CPAP users who stopped using it for 7 days before sleep testing. Half of the participants in each study were randomly assigned to the orforglipron group, and the other half were randomly assigned to the placebo group. Neither the researchers nor participants knew which group they were assigned to.
- The 2 trials were conducted at 66 medical centers and hospitals across North America, South America, Europe and Asia between October 2024 and July 2026.
- Researchers conducted overnight sleep studies at baseline, week 24 and week 52 to measure how often participants' breathing was interrupted due to either partial or complete upper airway collapse during sleep. An overnight sleep study uses sensors to monitor breathing, oxygen levels, heart rhythm, brain waves and body movements continuously during sleep.
- Vital signs (including body weight and blood pressure), patient-reported outcomes and inflammation markers were also measured at baseline, week 24 and week 52, with vital signs also checked at other visits throughout the study. Final blood pressure measures were conducted at week 48 rather than week 52, since CPAP was paused for seven days before the last sleep study, which can affect blood pressure measures.
- The study had several limitations. It did not evaluate patient outcomes beyond one year. People with Type 1 or Type 2 diabetes or mild sleep apnea were excluded from both trials, and some racial and ethnic groups were underrepresented in the study groups. Longer studies with more diverse populations are needed to evaluate long-term cardiovascular health outcomes in patients with obstructive sleep apnea from treatment with orforglipron.
Co-authors and disclosures are listed in the abstract. Eli Lilly and Company funded the studies.
Statements and conclusions of studies that are presented at the American Heart Association's scientific meetings are solely those of the study authors and do not necessarily reflect the Association's policy or position. The Association makes no representation or guarantee as to their accuracy or reliability. Abstracts presented at the Association's scientific meetings are not peer-reviewed, rather, they are curated by independent review panels and are considered based on the potential to add to the diversity of scientific issues and views discussed at the meeting. The findings are considered preliminary until published as a full manuscript in a peer-reviewed scientific journal.
