Role of Tesamorelin in HIV-Associated Lipodystrophy
Tesamorelin is the first and only FDA-approved treatment specifically indicated for reducing excess abdominal fat in patients with HIV-associated lipodystrophy, demonstrating a 15-18% reduction in visceral adipose tissue after 26 weeks of therapy. 1
Mechanism and Efficacy
Tesamorelin is a synthetic analog of human growth hormone-releasing hormone that stimulates the synthesis and release of endogenous growth hormone. Its primary effects include:
- Significant reduction in visceral adipose tissue (VAT) by approximately 15-18% after 26 weeks 1, 2
- Maintenance of VAT reduction with continued therapy for up to 52 weeks 3, 4
- No clinically significant effect on subcutaneous adipose tissue 3, 4
- Improvements in other body composition measures including trunk fat and waist circumference 4
- Improvement in body image parameters, particularly belly image distress 3, 4
Patient Selection
Tesamorelin therapy is most beneficial for:
- HIV patients with central fat accumulation (lipohypertrophy) 1
- Patients with metabolic syndrome 5
- Individuals with elevated triglyceride levels (>1.7 mmol/L) 5
- White race patients (who showed better response in clinical trials) 5
The odds of achieving a VAT reduction to <140 cm² (a level associated with lower health risks) is 3.9 times greater with tesamorelin than with placebo 5.
Dosage and Administration
- Recommended dose: 1.4 mg (0.35 mL of reconstituted solution) 1
- Administration: Subcutaneous injection once daily 1
- Duration: Long-term therapy is required as discontinuation results in reaccumulation of VAT 3, 4
Metabolic Effects and Benefits
Beyond VAT reduction, tesamorelin offers additional metabolic benefits:
- Decreased triglyceride levels (reduction of approximately 50 mg/dL) 2
- Improved total cholesterol to HDL cholesterol ratio 2
- Increased IGF-I levels by approximately 81% 2
Safety Considerations and Adverse Effects
Common adverse reactions include:
Important safety considerations:
- Risk of hyperglycemia and potential for developing diabetes 1
- Treatment-emergent serious adverse events occur in <4% of patients during 26 weeks of therapy 3
- Long-term cardiovascular safety has not been established 1
Contraindications
Tesamorelin should not be used in patients with:
- Active malignancy 1
- Disruption of the hypothalamic-pituitary axis 1
- Hypersensitivity to tesamorelin 1
- Pregnancy 1
Clinical Perspective
Prior to tesamorelin, there was no clearly effective therapy for fat accumulation in HIV-associated lipodystrophy 6, 1. HIV lipodystrophy is a complex condition characterized by fat maldistribution (both lipoatrophy and fat accumulation) often accompanied by metabolic abnormalities including insulin resistance and hyperlipidemia 6.
While tesamorelin effectively addresses visceral fat accumulation, it's important to note that it doesn't address the fat wasting (lipoatrophy) component of HIV lipodystrophy that commonly affects the face and extremities 6.