What is Tesamorelin (TESA Peptide)?
Tesamorelin is an FDA-approved synthetic growth hormone-releasing factor (GRF) analogue specifically indicated for reducing excess visceral abdominal fat in HIV-infected patients with lipodystrophy. 1, 2
Mechanism of Action
Tesamorelin is a synthetic peptide analogue of human growth hormone-releasing factor that stimulates the pituitary gland to produce and release endogenous growth hormone. 1, 3 This mechanism differs from direct recombinant human growth hormone (rhGH) administration and may offer better tolerability with fewer adverse effects. 3
FDA-Approved Indication
- Specific indication: Reduction of excess abdominal fat (visceral adipose tissue) in HIV-infected patients with lipodystrophy 1, 2
- FDA approval date: November 2010 1, 2
- Brand name: Egrifta 2
Dosing Regimen
Standard dose: 2 mg administered subcutaneously once daily 4
The medication demonstrated significant efficacy in Phase III clinical trials, with:
- 15-20% reduction in visceral adipose tissue (VAT) over 6-12 months 5
- Significant decrease in waist circumference after 26 weeks of treatment 1
- Maintained VAT improvements through 52-week extension phases 1
Required Monitoring
Metabolic Parameters
- Glucose monitoring: Assess fasting glucose and hemoglobin A1c levels regularly, as tesamorelin can affect glucose homeostasis 5
- Lipid panel: Monitor triglyceride levels, which showed significant improvement in treatment responders (defined as ≥8% VAT reduction) 5
- Adiponectin levels: Track changes as responders demonstrated significant improvements compared to nonresponders 5
Body Composition Assessment
- Visceral adipose tissue: Ideally measured by imaging (MRI or CT) to assess treatment response 5, 4
- Waist circumference: Clinical measurement as a practical surrogate marker 1
Safety Monitoring
- Adverse events: Monitor for injection site reactions and general tolerability 1
- Glycemic control: Particularly important as responders showed preservation of glucose homeostasis while nonresponders experienced worsening 5
Clinical Efficacy Data
Treatment responders (≥8% VAT reduction) experienced superior metabolic outcomes compared to nonresponders:
- Greater triglyceride reduction at 26 weeks (-0.6 vs -0.1 mmol/L, P=0.005) and 52 weeks (-0.8 vs 0.0 mmol/L, P=0.003) 5
- Attenuated glucose increases at 26 weeks (1 vs 5 mg/dL, P=0.01) and 52 weeks (-1 vs 8 mg/dL, P<0.001) 5
- Improved hemoglobin A1c preservation at both time points 5
Contemporary Relevance
Tesamorelin remains effective and well-tolerated in patients on modern integrase inhibitor (INSTI)-based antiretroviral regimens, which are now the standard of care for HIV treatment. 4 Despite INSTI-associated weight gain and adipose dysfunction, tesamorelin produced:
- Significant visceral fat reduction (median -25 cm² vs +14 cm² with placebo, P=0.001) 4
- Hepatic fat reduction (-4.2% vs -0.5%, P=0.01) 4
- Improved trunk-to-appendicular fat ratio (-0.1 vs 0.0, P=0.03) 4
- No exacerbation of glycemic control 4