New injection makes fat cells self-destruct
Scientists have developed an experimental injection that destroys fat cells and significantly reduces dangerous belly fat, potentially opening a new path to treating obesity. Early research also suggests it could help prevent the weight regain that often follows stopping popular weight loss drugs like Ozempic and Wegovy.
Key points
- An experimental injection called CBL-514 causes fat cells to self-destruct and reduced visceral fat in early human trials.
- At four weeks after the final injection, treated participants had a 12.01% average visceral fat reduction versus a 5.68% increase on placebo.
- The drug was generally well tolerated, with mostly mild to moderate injection-site reactions and no serious adverse events.
An experimental injection that makes fat cells destroy themselves showed promising results in early human trials, significantly reducing deep abdominal fat. The drug, CBL-514, was presented at the annual meeting of the European Association for the Study of Diabetes in Milan, Italy. Researchers say it could eventually offer a new way to treat obesity and help people maintain weight loss after stopping popular weight loss medications.
The treatment targets both subcutaneous fat, which sits just beneath the skin, and visceral fat, which surrounds internal organs. Dr. W. Timothy Garvey of the University of Alabama at Birmingham said the findings also raise the possibility that CBL-514 could reduce weight regain after patients stop GLP-1 receptor agonist drugs such as Ozempic, Wegovy, Mounjaro and Zepbound. However, that potential benefit has so far been shown only in animal studies and still needs confirmation in humans.
How the injection works
CBL-514 does not simply reduce the fat stored inside existing cells. It triggers apoptosis, a natural self-destruction process that causes cells to break down and die. The drug is designed to target adipocytes, the body's fat-storing cells, while leaving other cell types unaffected.
In phase 2 clinical trials, 69.6% of participants treated with CBL-514 lost at least 150 mL of subcutaneous fat by the eight-week follow-up. None of the placebo participants reached that threshold. In animal studies, the drug also reduced body weight and both subcutaneous and visceral abdominal tissue.
We expect that patients will be pleased by the cosmetic effects, such as the flatter stomach that can come with subcutaneous fat loss. But it is the reduction in body weight, loss of visceral fat and the improvements in blood pressure, cholesterol and the like that should be associated with this that will be important for health.
— Professor Garvey
Human trial results
Garvey and Yu-Fang Ling of Caliway Biopharmaceuticals, the drug's developer in New Taipei City, Taiwan, analyzed data from two phase 2 trials, CBL-0204 and CBL-0205. Participants with a BMI of 22 to 30 kg/m2 received injections into the lower abdomen every three weeks for up to 12 weeks, at doses up to 600 mg of CBL-514 (n=23) or placebo (n=17).
Before treatment, average visceral fat volume was 563.85 mL in the CBL-514 group and 659.81 mL in the placebo group. Four weeks after the final injection, the treatment group had a 12.01% average reduction in visceral fat, while the placebo group increased by 5.68%, a 17.69 percentage point difference. At the later follow-up, visceral fat in the CBL-514 group remained 10.45% below baseline, compared with an 11.76% average increase on placebo.
The drug was generally well tolerated. Most side effects were temporary reactions around the injection site, including pain, swelling and redness, and were generally mild to moderate. No serious adverse events were reported.
