Lilly’s experimental drug now shows benefits across obesity, diabetes, other conditions
Experimental therapy helped patients lose weight while improving blood sugar control, knee osteoarthritis pain and obstructive sleep apnea.
- Jun 8, 2026,
- Updated Jun 8, 2026 10:53 AM IST
Retatrutide, Eli Lilly’s experimental obesity drug, helped patients lose weight while also helping control type 2 diabetes, knee osteoarthritis pain and obstructive sleep apnea in Phase 3 studies, as drugmakers look to show that obesity medicines can address a range of related health conditions.
The results, presented at the American Diabetes Association’s Scientific Sessions, came from Lilly’s TRIUMPH-1 obesity trial and TRANSCEND-T2D-1 diabetes study. The study was also published in The Lancet.
The findings come as drugmakers race to expand the use of obesity medicines beyond weight management and diabetes into related conditions such as cardiovascular disease, sleep apnea and osteoarthritis. This could help support broader adoption of such therapies.
In the 80-week TRIUMPH-1 study, participants receiving the highest 12 mg dose of retatrutide lost an average of 70.3 pounds, or 28.3% of their body weight. Lilly said 65.3% of participants on the dose achieved a body mass index (BMI) below 30, while 33.3% reached a BMI below 25.
MUST READ | Lilly's obesity drug retatrutide helps patients lose up to 30% weight in Phase 3 trial
The company said retatrutide also reduced knee osteoarthritis pain and improved moderate-to-severe obstructive sleep apnea among participants enrolled in dedicated sub-studies. Knee osteoarthritis pain scores fell by up to 73.1%, while sleep apnea severity, measured by the apnea-hypopnea index, improved by up to 60.6%.
In the TRANSCEND-T2D-1 study involving adults with type 2 diabetes, participants achieved HbA1c reductions of up to 2 percentage points from a baseline of 7.9% after 40 weeks of treatment. Up to 90% achieved HbA1c levels below 7%, while up to 46% reached levels below 5.7%, a threshold for normal blood sugar levels. Participants receiving the 12 mg dose lost an average of 36.6 pounds, or 16.8% of their body weight.
The studies also showed improvements in several cardiovascular risk markers. In the obesity study, retatrutide reduced triglycerides by up to 41%, non-HDL cholesterol by up to 24.2% and systolic blood pressure by up to 12.3 mmHg. Similar improvements were reported in the diabetes study.
“Obesity drives more than 200 downstream diseases, yet we have historically treated those conditions one at a time and in silos,” said Ania Jastreboff, professor of medicine and pediatrics at Yale School of Medicine and lead investigator of the studies. “In TRIUMPH-1 and TRANSCEND-T2D-1, treatment with retatrutide resulted in substantial weight reduction together with clinically meaningful improvements in glycemia, knee osteoarthritis pain, and obstructive sleep apnea.”
“Across TRIUMPH-1 and TRANSCEND-T2D-1, retatrutide delivered substantial weight loss, meaningful A1C reduction, and improvements in knee osteoarthritis pain and moderate-to-severe obstructive sleep apnea,” said Kenneth Custer, executive vice president and president of Lilly Cardiometabolic Health.
Retatrutide is a once-weekly triple hormone receptor agonist that targets GIP, GLP-1 and glucagon receptors. Lilly is studying the drug across a range of conditions, including obesity, type 2 diabetes, sleep apnea, cardiovascular and renal outcomes, chronic low back pain and metabolic dysfunction-associated steatotic liver disease. The drug has not yet been approved and remains under clinical development.
The most commonly reported side effects included nausea, diarrhoea, vomiting and constipation. Lilly said these events were generally mild to moderate, and most participants continued treatment.
Retatrutide, Eli Lilly’s experimental obesity drug, helped patients lose weight while also helping control type 2 diabetes, knee osteoarthritis pain and obstructive sleep apnea in Phase 3 studies, as drugmakers look to show that obesity medicines can address a range of related health conditions.
The results, presented at the American Diabetes Association’s Scientific Sessions, came from Lilly’s TRIUMPH-1 obesity trial and TRANSCEND-T2D-1 diabetes study. The study was also published in The Lancet.
The findings come as drugmakers race to expand the use of obesity medicines beyond weight management and diabetes into related conditions such as cardiovascular disease, sleep apnea and osteoarthritis. This could help support broader adoption of such therapies.
In the 80-week TRIUMPH-1 study, participants receiving the highest 12 mg dose of retatrutide lost an average of 70.3 pounds, or 28.3% of their body weight. Lilly said 65.3% of participants on the dose achieved a body mass index (BMI) below 30, while 33.3% reached a BMI below 25.
MUST READ | Lilly's obesity drug retatrutide helps patients lose up to 30% weight in Phase 3 trial
The company said retatrutide also reduced knee osteoarthritis pain and improved moderate-to-severe obstructive sleep apnea among participants enrolled in dedicated sub-studies. Knee osteoarthritis pain scores fell by up to 73.1%, while sleep apnea severity, measured by the apnea-hypopnea index, improved by up to 60.6%.
In the TRANSCEND-T2D-1 study involving adults with type 2 diabetes, participants achieved HbA1c reductions of up to 2 percentage points from a baseline of 7.9% after 40 weeks of treatment. Up to 90% achieved HbA1c levels below 7%, while up to 46% reached levels below 5.7%, a threshold for normal blood sugar levels. Participants receiving the 12 mg dose lost an average of 36.6 pounds, or 16.8% of their body weight.
The studies also showed improvements in several cardiovascular risk markers. In the obesity study, retatrutide reduced triglycerides by up to 41%, non-HDL cholesterol by up to 24.2% and systolic blood pressure by up to 12.3 mmHg. Similar improvements were reported in the diabetes study.
“Obesity drives more than 200 downstream diseases, yet we have historically treated those conditions one at a time and in silos,” said Ania Jastreboff, professor of medicine and pediatrics at Yale School of Medicine and lead investigator of the studies. “In TRIUMPH-1 and TRANSCEND-T2D-1, treatment with retatrutide resulted in substantial weight reduction together with clinically meaningful improvements in glycemia, knee osteoarthritis pain, and obstructive sleep apnea.”
“Across TRIUMPH-1 and TRANSCEND-T2D-1, retatrutide delivered substantial weight loss, meaningful A1C reduction, and improvements in knee osteoarthritis pain and moderate-to-severe obstructive sleep apnea,” said Kenneth Custer, executive vice president and president of Lilly Cardiometabolic Health.
Retatrutide is a once-weekly triple hormone receptor agonist that targets GIP, GLP-1 and glucagon receptors. Lilly is studying the drug across a range of conditions, including obesity, type 2 diabetes, sleep apnea, cardiovascular and renal outcomes, chronic low back pain and metabolic dysfunction-associated steatotic liver disease. The drug has not yet been approved and remains under clinical development.
The most commonly reported side effects included nausea, diarrhoea, vomiting and constipation. Lilly said these events were generally mild to moderate, and most participants continued treatment.