Even after accounting for belly fat loss, tesamorelin still increased lean muscle in people with HIV and belly fat, suggesting other factors are involved.

This drug didn’t just make muscles less fatty—it also made them bigger in size, adding about half a square inch of lean muscle in the core area after six months.

People with HIV and belly fat who responded to tesamorelin had 0.64 to 1.08 square centimeters more lean muscle in their trunk muscles compared to those who didn't take the drug.

HIV patients with belly fat who responded to tesamorelin had more lean muscle mass in all four trunk muscles, with increases between 0.64 and 1.08 cm² compared to placebo after 26 weeks.

When belly fat went down in these patients, their trunk muscles also got less fatty—suggesting the same process might be cleaning up both types of fat.

For HIV patients with belly fat who responded to this drug, taking tesamorelin for 6 months made their trunk muscles less fatty and more dense, like turning soft muscle into firmer muscle.