Peptides for Appetite Suppression

3 research peptides are currently studied for appetite suppression. This guide ranks them by evidence strength and covers their mechanisms, safety profiles, and current clinical status.

Cholecystokinin (CCK) is a well-studied endogenous peptide that plays a crucial role in the gut-brain axis. Released in response to dietary fat and protein, CCK is known to facilitate meal termination by inducing feelings of satiety. It operates through CCK-A receptors in peripheral tissues and CCK-B receptors in the central nervous system, influencing both digestive processes and appetite regulation. Despite its established physiological role, the potential for CCK as a therapeutic agent for weight loss is limited due to rapid tachyphylaxis, where the body quickly becomes less responsive to its effects. Research indicates that while CCK can effectively stimulate gallbladder contraction and enhance pancreatic enzyme secretion, the short-lived nature of its appetite-suppressing effects poses challenges for sustained therapeutic use. Thus, while CCK remains a significant subject of study, its application in appetite suppression therapies is currently constrained.

Peptide YY (PYY) is a 36-amino-acid hormone released by L-cells in the ileum and colon following food intake. The primary circulating form, PYY3-36, acts on Y2 receptors located in the hypothalamic arcuate nucleus, leading to a marked suppression of appetite. Human infusion studies have consistently demonstrated that PYY can reduce caloric intake by approximately 30%, making it one of the most effective hormones identified in appetite regulation. Notably, research has shown that individuals with obesity often present with lower postprandial levels of PYY, suggesting a potential therapeutic avenue for enhancing satiety in this population. However, the clinical development of PYY-based therapies has been complicated by side effects such as nausea at doses that effectively reduce appetite. This presents a challenge in balancing efficacy and tolerability in potential treatments aimed at weight management.

Tesofensine, a triple monoamine reuptake inhibitor targeting serotonin, norepinephrine, and dopamine, was initially developed for neurodegenerative diseases such as Alzheimer's and Parkinson's. Its potential as a weight loss agent has gained attention through Phase II trials, which reported an approximate 10% reduction in body weight over a 24-week period. While not a peptide, tesofensine is frequently discussed in the context of peptide-based appetite suppression therapies due to its significant effects on weight loss and appetite modulation. The compound, developed by NeuroSearch A/S and later licensed to Saniona, is currently pursuing Phase III clinical trials to further establish its efficacy and safety profile. However, as with any investigational drug, the outcomes of these trials will be critical in determining its future role in obesity treatment and appetite suppression.