Stanford Medicine researchers have identified a naturally occurring molecule that may suppress appetite and reduce body weight much like Ozempic, but without several of its common side effects.
The molecule, named BRP (BRINP2-related peptide), is a tiny peptide of just 12 amino acids that the human body already produces naturally. In animal studies, it reduced food intake by up to 50% in both mice and minipigs, with nearly all weight loss coming from body fat rather than muscle.
Unlike semaglutide (the active ingredient in Ozempic and Wegovy), which activates receptors throughout the brain, gut, pancreas, and other tissues—causing nausea, constipation, and sometimes muscle loss—BRP appears to act specifically in the hypothalamus, the brain's appetite and metabolism control center.
"The receptors targeted by semaglutide are found in the brain but also in the gut, pancreas and other tissues. That's why Ozempic has widespread effects," said senior author Katrin Svensson, PhD, assistant professor of pathology at Stanford. "In contrast, BRP appears to act specifically in the hypothalamus."
The discovery was driven by an AI algorithm called Peptide Predictor, which searched all 20,000 human protein-coding genes for sites where prohormone convertases cut proteins into active hormone fragments. The team focused on prohormone convertase 1/3, an enzyme linked to obesity, narrowing to 373 prohormones and 2,683 possible peptides.
From these, they selected 100 for laboratory testing. One tiny peptide—only 12 amino acids long—produced a tenfold increase in neuronal activity compared to untreated controls, far outpacing even GLP-1.
In obese mice treated daily for 14 days, BRP produced an average 3-gram weight loss while control mice gained weight. The treated animals also showed improved glucose tolerance and insulin sensitivity. No signs of nausea, constipation, or muscle loss were observed.
Svensson has co-founded Merrifield Therapeutics to bring BRP toward human clinical trials. The research was published March 5 in Nature, led by senior research scientist Laetitia Coassolo, PhD.
"The lack of effective drugs to treat obesity in humans has been a problem for decades," Svensson said. "Nothing we've tested before has compared to semaglutide's ability to decrease appetite and body weight. We are very eager to learn if it is safe and effective in humans."
