From Ars Technica · · 2m
Obesity drug cuts weight by 25 percent in trial
Retatrutide, a triple-acting hormone treatment from Eli Lilly, showed the strongest weight loss results yet in late-stage testing.
In brief
Retatrutide, a triple-acting hormone treatment from Eli Lilly, showed the strongest weight loss results yet in late-stage testing. Retatrutide reduced body weight by an average of 25 percent in obese patients over 80 weeks, with results published in the New England Journal of Medicine. Originally reported by Ars…
Triple hormone drug shows strongest results
Retatrutide, developed by Eli Lilly, produced the most powerful weight loss results yet. Patients on the highest dose lost an average of 25 percent of body weight after 80 weeks.
Extended trial showed 30 percent loss
After an extension period to 104 weeks, patients lost an average of 30 percent of their body weight. More than a third of participants lost 30 percent or more.
Drug reduced obesity-related conditions
Retatrutide reduced knee pain by up to 62 percent in participants with obesity-linked knee osteoarthritis. It reduced sleep apnea events by up to 57 percent in those with obstructive sleep apnea.
Cardiometabolic improvements across the board
The drug improved blood pressure, triglycerides, and low density lipoprotein cholesterol. More than 90 percent of participants with prediabetes saw the condition resolve by trial end.
Trial included 2,339 people across 11 countries
The trial began in 2023 with participants from 131 clinical trial sites in 11 countries. Participants received either 4 mg, 9 mg, 12 mg of retatrutide, or placebo. Average starting weight was around 113 kg.
How retatrutide works differently
Retatrutide combines three hormones: GLP-1, GIP, and glucagon. It builds on Eli Lilly's tirzepatide and Novo Nordisk's semaglutide by adding glucagon to the mix of the other two hormones.
Single peptide mimics three hormones
Retatrutide's active ingredient is a single synthetic peptide that interacts with receptors for all three hormones. Compared to GIP, the drug is nearly nine times more potent. It stays active for six days, allowing weekly injections.
Trial lacked direct comparison to existing drugs
The trial did not compare retatrutide to existing treatments like tirzepatide. How it compares in weight loss and health benefits will need to be explored in future trials.
Safety profile similar to existing drugs
The most common side effects were mild to moderate gastrointestinal symptoms like nausea, diarrhea, and constipation. Ten participants had cardiovascular events and ten reported pancreatitis, but the study was too small to assess these rare risks.
What it means
Retatrutide reduced body weight by an average of 25 percent in obese patients over 80 weeks, with results published in the New England Journal of Medicine.
