The drug makes the body produce more IGF-1 — a hormone linked to growth and metabolism — which is exactly what you’d expect from a drug that stimulates growth hormone.

The injection makes the body produce more of a natural growth-related hormone called IGF-1, which helps explain how it reduces belly fat.

Tesamorelin boosts a key growth hormone-related protein in HIV patients without affecting their blood sugar levels.

The drug shrinks the fat around the torso and makes the waist smaller, but doesn’t change the fat on the arms, legs, or just under the skin — meaning it targets only the dangerous internal fat.

Denser under-the-skin fat in HIV patients on tesamorelin was linked to higher IGF-1 levels, a hormone involved in growth and metabolism, suggesting broader metabolic benefits.

A hormone treatment called tesamorelin raises IGF-1 hormone levels more than a placebo in people with HIV at 2 weeks, 3 months, and 6 months of treatment.