What is Tesamorelin?

Tesamorelin is a synthetic peptide that mimics your body’s natural growth hormone–releasing hormone (GHRH). It’s a 44–amino-acid analogue designed to be more stable than native GHRH, so it lasts longer in the bloodstream and more reliably stimulates the pituitary gland.

When Tesamorelin binds to GHRH receptors in the anterior pituitary, it triggers pulsatile secretion of growth hormone (GH), which then raises insulin-like growth factor 1 (IGF-1) and activates pathways that:

• Increase lipolysis (fat breakdown), especially in visceral adipose tissue (VAT)
• Support protein synthesis and muscle maintenance
• Influence glucose and lipid metabolism

In the U.S., tesamorelin is marketed as EGRIFTA® / EGRIFTA SV® / EGRIFTA WR®, and is FDA-approved only for reducing excess abdominal (visceral) fat in adults with HIV-associated lipodystrophy.

Targeted Visceral Fat Reduction

Visceral fat (the fat packed around your abdomon) is strongly linked to insulin resistance, dyslipidemia, fatty liver, and cardiovascular risk. Tesamorelin’s clearest and strongest clinicals are in the reduction of VAT in people with HIV-associated central adiposity.

Phase 3 trials in HIV lipodystrophy

In large randomized, placebo-controlled trials of >400 antiretroviral-treated adults with HIV and excess abdominal fat:

• Visceral adipose tissue decreased by ~15–20% over 6–12 months with Tesamorelin versus placebo.
• The greatest absolute VAT reductions were seen in patients with the highest baseline visceral fat.
• Importantly, subcutaneous fat was largely preserved. Tesamorelin reduced “dangerous” visceral fat without stripping beneficial subcutaneous stores.

Tesamorelin’s strongest evidence is in selectively reducing visceral belly fat in HIV-associated lipodystrophy, without acting as a generic, whole-body “weight loss drug.”

Metabolic Benefits Beyond Fat Volume

Because visceral fat is tightly tied to cardiometabolic risk, shrinking VAT often improves lab markers. Across multiple studies and pooled analyses:

• Tesamorelin therapy improved lipid profiles, with reductions in:
  • Triglycerides
  • Non-HDL cholesterol
• Responders (those with clinically meaningful VAT reduction) showed:
  • Greater drops in triglycerides
  • Increases in adiponectin, a hormone that improves insulin sensitivity and lipid handling

Glucose metabolism is more nuanced:

• Some trials in people with HIV showed no major deterioration in glucose control over the short term.
• However, the FDA label notes an increased incidence of elevated HbA1c (≥6.5%) and new diabetes vs placebo (about 5% vs 1% at 26 weeks; hazard ratio ~3.3). Ongoing glucose monitoring is recommended.

Emerging Data for Liver Disease

Because visceral fat and liver fat are tightly linked, researchers have looked at Tesamorelin in non-alcoholic fatty liver disease (NAFLD / MASLD) in people with HIV.

In a published randomized trial of HIV-positive adults with abdominal fat accumulation:

• 6 months of tesamorelin led to:
  • Significant reductions in VAT
  • Modest but statistically significant reductions in liver fat (hepatic lipid content) compared with placebo
• The drop in liver fat tracked closely with the decrease in visceral fat, suggesting a mechanistic link (GH-mediated lipolysis, reduced de novo lipogenesis, etc.)

Follow-up analyses show:

• Clinically meaningful VAT reductions on Tesamorelin were associated with improved liver enzymes and potentially lower risk of steatohepatitis progression, though long-term outcome data are still limited.

Muscle Quality and Body Composition

Another interesting line of research looks at muscle quality

Secondary analyses of CT-based body composition data in HIV-positive adults on Tesamorelin showed:

• Increased skeletal muscle density with less fat infiltration in muscle
• Increased trunk muscle area, especially in abdominal and rectus muscle groups
• These changes were most pronounced in patients who achieved significant VAT reduction

Improved muscle density is associated with:

• Better strength and physical function
• Lower frailty risk with aging

Building on this, an ongoing clinical trial (NCT06554717) is evaluating tesamorelin as an adjunct to exercise to see whether it can:

• Enhance muscle mass and quality
• Improve physical function and quality of life in adults with HIV.

Common Side Effects

According to the FDA label and post-marketing data, the most frequently reported adverse reactions include:

• Injection site reactions (redness, itching, pain, swelling)
• Joint pain, extremity pain, peripheral edema, carpal tunnel–like symptoms
• Myalgias (muscle aches)
• Lab changes: elevated IGF-1, occasional hyperglycemia or glucose intolerance

Glucose & Diabetes Risk

• In clinical trials, new or worsening glucose intolerance occurred more often with Tesamorelin than placebo (HbA1c ≥ 6.5% in ~5% vs 1% at 26 weeks).

Cancer and Pituitary Issues

Because tesamorelin stimulates GH production, it is contraindicated in certain situations:

• Active malignancy (new or recurrent cancer). This includes any active solid tumor (for example, breast, prostate, colorectal, lung, melanoma, ovarian, endometrial, pancreatic cancers) and hematologic cancers such as lymphoma and leukemia. Any prior cancer should be fully treated, inactive, and in remission before considering Tesamorelin, and therapy should be stopped if there is evidence of recurrence.
• Disruption of the hypothalamic–pituitary axis (pituitary tumors, prior pituitary surgery, significant head irradiation or trauma). For example: pituitary tumors, prior pituitary surgery (hypophysectomy), established hypopituitarism, or significant head irradiation or head trauma affecting the hypothalamic–pituitary region.
• Known hypersensitivity to Tesamorelin or its excipients
• Pregnancy and pediatric use (<18 years)

For people with past, treated malignancies, labels and clinical policies recommend careful, individualized risk–benefit discussion due to the theoretical risk of stimulating tumor growth via GH/IGF-1.

How does Tesamorelin compare with other GH-axis treatments?

How Tesamorelin Stimulates the Pituitary

Tesamorelin is a GHRH analog, meaning it mimics your body’s natural Growth Hormone–Releasing Hormone.

This causes the pituitary to:

• Release more Growth Hormone (GH)
• Release GH in stronger pulse
• Release GH in normal circadian rhythm (mostly at night)

Increased GH → Liver Makes IGF-1

GH travels through the bloodstream to the liver.

The liver then produces:

• Insulin-Like Growth Factor-1 (IGF-1)

IGF-1 is what drives most of the:

• Muscle-building effects
• Fat metabolism
• Tissue repair and growth, including connective tissue and organ remodeling
• Collagen synthesis and extracellular matrix effects in muscle and other tissues
• Bone and organ benefits as part of the GH–IGF axis’ role in somatic growth and maintenance

Do you need a prescription for Tesamorelin?

Yes. Tesamorelin and all compounded medications require a prescription to be used safely and legally.

Bowery Clinic is a concierge longevity and peptide virtual clinic designed for people who want a higher standard of care than traditional telemedicine. We focus on advanced peptide therapy, recovery, muscle optimization, metabolic support, and long-term vitality.

At Bowery Clinic, all treatments are dispensed through licensed 503A, FDA-registered compounding pharmacies, ensuring high-quality peptides with verified sterility, potency, and COAs. No unregulated sources. No “research peptides.” No risks from black-market products.

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