Alexamorelin

Alexamorelin acts as a potent and selective agonist of the growth hormone secretagogue receptor (GHS-R1a), mimicking the action of endogenous ghrelin.

• GH Stimulation: By binding to GHS-R1a in the pituitary gland, it induces the release of growth hormone (GH) and consequently increases insulin-like growth factor 1 (IGF-1) levels.
• Orexigenic effect: It activates neurons in the hypothalamus (especially the arcuate nucleus) that express neuropeptide Y (NPY) and agouti-related protein (AgRP), stimulating appetite and food intake.
• Anabolic action: It promotes muscle protein synthesis and reduces protein degradation, contributing to increased lean body mass and improved muscle function.
• Metabolic effects: It modulates glucose and lipid metabolism, with potential to improve insulin sensitivity in certain contexts.

• Cancer cachexia: Primary investigational indication to treat weight loss and muscle wasting in oncology patients.
• Cardiac and pulmonary cachexia: Evaluated in chronic heart failure and COPD to improve nutritional status and physical function.
• Growth disorders: Potential use in children and adults with growth hormone deficiency.
• Post-surgical recovery: Studied to accelerate muscle and metabolic recovery after major surgeries.

The main effects of Alexamorelin include a significant increase in appetite and caloric intake, leading to body weight gain, primarily lean mass. Improvement in muscle strength and functional capacity is also observed in cachectic patients. Hormonally, it elevates GH and IGF-1 levels, with potential anabolic and osteogenic effects. It may cause a mild increase in fasting blood glucose and changes in insulin sensitivity. In some studies, a reduction in fatigue and improvement in quality of life have been reported.

Alexamorelin is contraindicated in patients with known hypersensitivity to the peptide or any of its components. It is not recommended in patients with active hormone-sensitive tumors (except in controlled clinical trials) due to the potential mitogenic effect of GH/IGF-1. The most common adverse effects include nausea, vomiting, dizziness, headache, mild hyperglycemia, and injection site reactions. Blood glucose should be monitored in diabetic patients or those with glucose intolerance. There is insufficient data on its safety during pregnancy and lactation. Its use should be supervised by a specialist physician in the context of clinical trials or expanded access programs.

Alexamorelin has not received approval from any regulatory agency (FDA, EMA, etc.) for marketing. It is in advanced clinical research (phase II and III trials) primarily for the treatment of cancer cachexia. To date, no New Drug Application (NDA) has been submitted to the FDA.

In clinical trials, typical doses of Alexamorelin range from 0.5 to 3 mg administered subcutaneously once or twice daily. The dose is adjusted based on patient response and tolerability. No standard approved dose exists.

Alexamorelin should be stored refrigerated between 2°C and 8°C, protected from light. Do not freeze. Once reconstituted, it should be used within 24 hours if kept at room temperature, or up to 7 days if refrigerated. Discard any unused solution after that period.