Body fat changes (lipodystrophy) are relatively common among HIV patients, especially in those who have been on longer treatment, who are older, and have had fluctuations in weight. Also, there are particular antiviral medications that are associated with these body changes. At CROI, 52 week, long-term safety and efficacy of tesamorelin was reported. Tesamorelin or placebo was given (randomized) to patients with increased abdominal fat -- lipodystrophy, daily by subcutaneous injection for 26 weeks. This phase was followed by another 26 weeks by which placebo patients received tesamorelin and the previous tesamorelin-treated individuals were re-randomized to continue for an additional 26 weeks or change to a placebo. At 52 weeks, from the study population of 275 men and 40 women there was a highly significant improvement in patients continuing on the drug, showing loss of 17 and 23% of abdominal fat respectively. Also, observed at 52 weeks was a sustained increase in body mass. Importantly, the drug did not alter glucose (blood sugar) metabolism or contribute to other adverse events, unlike growth hormone (Serostim). An added benefit was a loss of triglycerides (blood fats, associated with increased cardiovascular risk).

Tesamorelin is a growth hormone releasing factor analogue. When tesamorelin is administered, the bio-feedback system of growth hormone release by the pituitary gland is still intact, avoiding excessive growth hormone levels and potential side effects. This distinguishes tesamorelin from Serostim. The reduction in both belly fat and triglycerides, without significantly effecting sugar levels, seen with tesamorelin use has the overall potential of reducing cardiovascular risk to patients with HIV disease (but individuals should also consider smoking cessation), as well as improving and enhancing their quality of life.

Dr. Dan Berger (Medical Director, Northstar Healthcare, Chicago) is an author of the article published in The New England Journal of Medicine on tesamorelin and an author of the abstract presented at CROI.