A new obesity drug has posted numbers that look bigger than anything else on the market, and the company behind it says the results hold up after more than two years of testing. The drug, called retatrutide, lost an average of 25 percent of body weight after 80 weeks in patients on the highest dose, and that number rose to 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 overall.
The findings appear in the New England Journal of Medicine. They come from a large, international trial that started in 2023 and included 2,339 participants from 131 sites in 11 countries. The trial split participants into four nearly equal groups, giving them 4 mg of retatrutide, 9 mg, 12 mg, or a placebo. The average starting weight was around 113 kg (250 pounds), and the average body mass index (BMI) was 40.
What the Numbers Show
The weight loss was not the only thing that moved. The drug also reduced knee pain by up to 62 percent in a subset of participants with obesity-linked knee osteoarthritis. It cut the number of sleep apnea events per hour by up to 57 percent in a subset with obesity-linked obstructive sleep apnea. Cardiometabolic measurements improved across the board, including blood pressure, triglycerides, and low-density lipoprotein 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. The trial design meant each group was nearly equal in size, which gives the comparisons some strength.
How the Trial Worked
The trial design was straightforward. Four groups, one placebo, and a long follow-up period. The 80-week mark showed an average 25 percent loss on the highest dose, and the 104-week mark pushed that number to 30 percent.
For the knee pain and sleep apnea results, the source specifies subsets: 574 participants had knee osteoarthritis, and 243 had obstructive sleep apnea. Those numbers matter because they show the sample sizes behind the claims, not just the percentages.
Why the Numbers Matter
A 30 percent weight loss over more than two years is a big number. The trial ran for 80 weeks, then extended to 104 weeks, and the weight loss kept climbing through both periods.
The resolution of prediabetes in more than 90 percent of participants who started with it is a notable outcome. Prediabetes is a warning sign, and a drug that removes it in most people who enter with it is doing something real.
The Knee Pain and Sleep Apnea Data
The knee pain reduction of up to 62 percent and the sleep apnea reduction of up to 57 percent both came from subsets of participants. That means the full population did not see those exact numbers, but the subsets did.
The 30 percent-or-more figure came from the total population, not just the highest-dose group. The trial design split participants into four nearly equal groups, which gives the comparisons some strength.
What is clear is that the drug worked on multiple fronts at once. Weight loss, knee pain, sleep apnea, blood pressure, triglycerides, and bad cholesterol — the pattern holds across all of them. That is a hard combination to produce, and the journal publication suggests the authors believe the evidence is strong enough to stand public scrutiny.
The Trump Administration Angle
The story does not end with the science. In June, news broke that top health officials in the Trump administration were involved in granting special access to the experimental medicine to a mystery 79-year-old in April. That person was widely speculated to be Trump, who was 79 at the time.
That angle is not part of the published data. It is a separate political story. The administration angle is outside the science.
What Comes Next
Retatrutide has been so sought after that the administration angle emerged at all. The drug is expected to be the most powerful formula yet, and the trial data supports that claim. The 25 percent and 30 percent weight loss numbers, the 90 percent resolution of prediabetes, and the 62 percent and 57 percent subset reductions all point in the same direction.
The trial ran for 80 weeks, then extended to 104 weeks. The data is in the journal now, and the question of whether retatrutide becomes available to the millions of Americans with obesity will depend on regulatory action, not just scientific publication.
Key Facts Box
- Trial started: 2023
- Participants: 2,339 from 131 sites in 11 countries
- Doses tested: 4 mg, 9 mg, 12 mg, placebo
- Average starting weight: 113 kg (250 pounds)
- Average BMI: 40
- Knee osteoarthritis subset: 574 participants
- Sleep apnea subset: 243 participants
- Weight loss at 80 weeks: 25 percent on highest dose
- Weight loss at 104 weeks: 30 percent on highest dose
- Prediabetes resolution: More than 90 percent of those who entered with it
The trial data is likely to ratchet up anticipation for the drug among the millions of Americans with obesity. The numbers are large, the consistency across multiple measures is striking, and the 104-week mark shows the effect holding rather than fading. The published paper appears in the New England Journal of Medicine.
The administration angle adds a layer of political spectacle, but the science stands on its own. The weight loss, the knee pain reduction, the sleep apnea reduction, the blood pressure, triglycerides, and bad cholesterol improvements — all of it points in the same direction. The published paper reports the data, and the data is strong.
The mystery 79-year-old remains a mystery. The drug’s future is clearer: it has shown what it can do in a large, well-designed trial, and the numbers justify the excitement.
Source material: “Most powerful obesity drug yet: People lost up to 25% of weight in trial,” Ars Technica.
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