Tesamorelin is an effective medication for reducing treatment-related visceral adipose fat (VAT) in patients with HIV, a common problem with antiretroviral therapy. Substudies of 2 positive phase 3 trials of this drug were presented here at the 50th Interscience Conference on Antimicrobial Agents and Chemotherapy (ICAAC).
Both studies showed that tesamorelin was effective in reducing VAT across different subgroups of HIV-infected patients, and that reductions could be easily measured using waist circumference. Moreover, patients treated with this drug reported improvement in body image, researchers announced.
“A pooled analysis of 2 phase 3 clinical trials showed the efficacy of tesamorelin in reducing VAT, regardless of age, gender, race, hepatitis status, or antiretroviral regimen. Also, waist circumference measurements correlated with reductions in VAT seen on computed tomography [CT] scans,” said Sophie Elise Michaud, PhD, an employee of Theratechnologies Inc. in Montreal, Quebec, who was coauthor of one of the studies.
Tesamorelin is an investigative analog of growth-hormone-releasing factor and growth-hormone-releasing hormone. The drug is pending approval by the US Food and Drug Administration (FDA), but some investigators are not enthusiastic about using it, except perhaps for specific indications.
Both substudies presented at ICAAC were based on pooled data from two 26-week studies that consisted of 816 HIV-positive patients randomized to tesamorelin or placebo. Mean age was 48 years, and about 85% were male. Mean body mass index at baseline was 29 kg/m2, mean waist circumference was 105 cm, and mean waist-to-hip ratio was 1.
At 26 weeks, tesamorelin significantly reduced VAT, compared with placebo, regardless of age (patients were divided into 2 groups — 47 years or younger and older than 47 years), sex, race (whites, blacks, or other races), hepatitis status, viral load (detectable or undetectable), or antiretroviral regimen (P < .01 for all analyses compared with placebo).
Long-term safety of tesamorelin was similar to that of the main study population in all subgroups. The lead author of this subgroup analysis was Julian Falutz, MD, from McGill University Health Centre in Montreal.
A second substudy of the same group of patients found that waist circumference was a useful and simple measurement to assess the magnitude of VAT reduction without having to resort to a CT scan, which was used in the original phase 3 studies. This analysis found that body image was improved and that this improvement correlated with reductions in VAT. Monica Zoltowska, PhD, an employee of Theratechnologies, was lead author of this substudy.
At week 26, waist circumference was reduced by 2.4 cm in patients treated with tesamorelin, compared with no reduction in the placebo group (P = .002). Belly appearance distress was also significantly improved from baseline in treated patients (P ≥ .15)
“Now we know that doctors can find out if the drug works by measuring waist circumference and asking patients about their level of body image distress,” Dr. Michaud said.
In Dr. Lundgren’s opinion, even if tesamorelin is approved, it will not be used that often. “As soon as the drug is stopped, the fat comes back, so treatment would have to be lifelong,” he explained. Patients with VAT could try diet and exercise for their bellies, he added.