Tesamorelin

Tesamorelin reduces excess abdominal visceral adipose tissue by approximately 15% after 26 weeks and 18% after 52 weeks of therapy in HIV-infected patients with lipodystrophy.¹,²,³ This reduction is associated with improvements in triglyceride levels, non-HDL cholesterol, adiponectin, and preservation of glucose homeostasis.¹,⁴ As a growth hormone-releasing factor analog, it increases skeletal muscle area and density, aiding in countering HIV-associated wasting.³,⁵ Studies indicate benefits on lipid profiles and fat quality independent of quantity changes.⁴ It is FDA-approved specifically for reducing excess abdominal fat in HIV patients with lipodystrophy.²,³

Common side effects of tesamorelin include injection site reactions such as redness, itching, pain, bruising, or swelling, as well as joint or muscle pain, pain or numbness in the hands or wrists, tingling sensations, swelling of the hands, feet, ankles, or lower legs, nausea, vomiting, heartburn, and night sweats.²,⁶,⁷ Serious side effects may involve allergic reactions manifesting as rash, hives, itching, flushing, swelling of the face or throat, shortness of breath, fast heartbeat, or dizziness, alongside potential increases in blood sugar levels that require monitoring, particularly in patients with prediabetes, insulin resistance, or diabetes.²,⁶,⁷,⁸,⁹ Safety considerations include promptly reporting severe symptoms to a healthcare provider, rotating injection sites to minimize local reactions, and regular blood glucose checks due to risks of hyperglycemia.²,⁶,⁸ Tesamorelin is generally well-tolerated long-term, with adverse events comparable to shorter-term use and no clinically significant glucose changes in studies.¹⁰ Patients should inform their doctor of any unusual problems and report serious effects via FDA MedWatch.⁶

Tesamorelin, a synthetic analog of growth hormone-releasing hormone (GHRH), binds to GHRH receptors on somatotroph cells in the anterior pituitary gland.³,¹¹,¹²,¹³ This binding activates G protein-coupled signaling pathways, including adenylyl cyclase stimulation, which promotes growth hormone (GH) gene transcription, somatotroph cell growth, and pulsatile release of endogenous GH into the bloodstream.³,¹²,¹³,¹⁴ The released GH then circulates to target tissues such as the liver, where it binds receptors to induce production of insulin-like growth factor-1 (IGF-1).¹²,¹³,¹⁴ IGF-1 mediates key physiological effects of GH, including enhanced lipolysis of visceral adipose tissue, improved glucose uptake, and regulation of body composition through anabolic and fat-reducing mechanisms.¹¹,¹²,¹³,¹⁴