Retatrutide trial shows average weight loss of up to 25% at 80 weeks, 30% at 104 weeks
Late-stage trial data show retatrutide produced average weight loss of up to 25% at 80 weeks and 30% at 104 weeks in people with obesity, with improvements in knee pain, sleep apnea and cardiometabolic measures.
The trial began in 2023 and included 2,339 participants at 131 clinical trial sites in 11 countries. Participants were divided into four nearly equal groups that received either 4 milligrams of retatrutide, 9 mg, 12 mg, or a placebo. Across all groups, the average starting weight was about 113 kilograms (250 pounds), and the average body mass index was 40.
Patients on the highest retatrutide dose lost an average of 25 percent of body weight after 80 weeks and 30 percent after an extension period to 104 weeks. More than a third of participants taking retatrutide lost 30 percent or more of their weight.
The trial also assessed subsets of participants. Among 574 participants with obesity-linked knee osteoarthritis, retatrutide reduced knee pain by up to 62 percent. Among 243 participants with obesity-linked obstructive sleep apnea, it reduced the number of sleep apnea events per hour by up to 57 percent.
The drug improved cardiometabolic measurements across the board, including blood pressure, triglycerides, and low-density lipoprotein cholesterol, or bad cholesterol. At the start, more than a third of trial participants had prediabetes; by the end, the condition had resolved in more than 90 percent of those participants.