HIV-Associated Lipodystrophy
Abnormal fat redistribution in HIV patients characterised by excess visceral fat and peripheral fat loss, increasing cardiometabolic risk. Tesamorelin is the only drug specifically approved for this condition, stimulating endogenous GH production to promote visceral fat lipolysis.
Technical Context
Prevalence: approximately 40-50% of HIV patients on cART (combination antiretroviral therapy), though rates are declining with newer regimens. Risk factors: older NRTIs (stavudine, zidovudine — strongest association with lipoatrophy), protease inhibitors (associated with dyslipidaemia and insulin resistance), duration of therapy, age, and baseline BMI. Pathophysiology: multifactorial — mitochondrial toxicity (NRTIs inhibit mitochondrial DNA polymerase-γ → impaired adipocyte mitochondrial function), altered adipokine production, increased inflammation, and direct viral effects. Cardiovascular risk: excess visceral fat increases coronary artery disease risk (already elevated in HIV). Tesamorelin (Egrifta): the only approved drug specifically for HIV lipodystrophy. Dosing: 2mg daily SC injection. Phase III results: approximately 15-18% reduction in trunk fat at 26 weeks vs placebo, maintained at 52 weeks with continued treatment. Lipodystrophy severity returns to baseline within 3-6 months of discontinuation. Tesamorelin does not significantly affect limb fat (lipoatrophy), which has different underlying pathophysiology.