A new experimental weight-loss drug from Eli Lilly is drawing serious attention after late-stage trial results showed patients losing an average of around 70 pounds. The drug, called Retatrutide, helped participants lose nearly 28% of their body weight over 80 weeks, according to results announced by the company on May 21.
The numbers are big enough that some doctors are already comparing its effects to bariatric surgery. Retatrutide is not yet approved by the US Food and Drug Administration, but experts speaking to TODAY believe approval could happen later this year once the company submits the drug for review.
How much weight did people lose with Retatrutide?
According to Eli Lilly, almost two-thirds of people taking the highest dose of Retatrutide managed to reduce their BMI below 30, moving them out of the obesity category.
Some participants with severe obesity who stayed on the medication during an extended part of the study lost even more weight over time. The company said this group lost up to an average of 85 pounds, or around 30% of their body weight, after two years.
“(This) basically starts to approximate what we see in bariatric surgery,” NBC medical contributor Dr. Natalie Azar said on TODAY.
Apart from weight loss, the drug also appeared to improve several heart-related risk factors. According to Azar, participants saw improvements in waist circumference, blood pressure and non-HDL cholesterol levels.
Is Retatrutide better than Ozempic?
There are currently no direct head-to-head studies comparing Retatrutide with popular weight-loss medications already available on the market. Still, the early numbers are giving doctors plenty to talk about.
Wegovy, which contains semaglutide, the same active ingredient found in Ozempic, works by copying one gut hormone known as GLP-1. On average, that leads to around 15% body weight loss.
Zepbound, or tirzepatide, targets two hormones, GLP-1 and GIP, helping users lose roughly 21% of body weight on average.
Retatrutide goes a step further. It mimics three hormones, including glucagon, which is why some experts are calling it a “triple-agonist” or “triple G”.
These hormones are linked to hunger control, calorie burning and fat metabolism. According to Azar, targeting more hormones appears to increase overall weight loss.
“It does seem like more is actually better. It does translate into more weight loss, the more hormones you’re targeting,” she said on TODAY.
“This is the largest weight loss I’ve ever seen in any medication trial,” Dr. Susan Spratt, an endocrinologist and senior medical director for the Population Health Management Office at Duke Health in North Carolina, told NBC News. She was not involved in the trial.
“This is huge.”
What are the side effects of Retatrutide?
The most common side effects reported during the trial were similar to those already seen with other weight-loss medications currently on the market.
Most involved gastrointestinal problems, including:
- Nausea
- Diarrhoea
- Constipation
- Vomiting
The trial results also listed upper respiratory tract infections, urinary tract infections and uncomfortable skin sensations as additional side effects.
Around 11% of participants stopped taking the drug because of adverse events. In comparison, roughly 5% of people in the placebo group discontinued treatment.
Who could benefit from Retatrutide?
Doctors speaking previously to TODAY.com said not everybody needs to lose such a large amount of weight, meaning the drug could feel “overpowering” for some overweight patients.
However, treatments capable of producing this level of weight loss may be particularly useful for people with severe obesity, especially those with a BMI of 35 or higher.
According to Azar, the drug may also help the group of patients who do not respond properly to existing GLP-1 medications and require something stronger.
She added that Retatrutide could potentially benefit people who initially lost weight with a GLP-1 drug but later hit a plateau.
ALSO READ: Think you’re healthy because you’re thin? Nutrition expert says look deeper
