(HealthDay News) – A new combination treatment of controlled-release phentermine/topiramate (PHEN/TPM CR) leads to significantly greater weight loss than a placebo even in individuals with significant obesity-related comorbidities, according to a study presented at the European Congress on Obesity, held from May 9–11 in Lyon, France.
Stephan Rössner, MD, PhD, from the Karolinska Institutet in Stockholm, and colleagues randomly assigned 2,487 subjects to placebo or one of two doses of PHEN/TPM CR: 7.5mg/46mg (7.5/46) or 15mg/92mg (15/92) for 56 weeks. Subjects were categorized according to the Edmonton Obesity Staging System (EOSS), which measures obesity-related morbidity, with most subjects having weight-related chronic disease (2,170 individuals) or established end-organ damage (180 individuals).
The researchers found that PHEN/TPM treatment was associated with significantly greater weight loss compared with placebo across all EOSS categories. Weight loss increased in a dose-response manner and ranged from 1.5%–2.3% for placebo, 6.8%–8.6% for 7.5/46 PHEN/TPM, and 9.5%–10.5% for 15/92 PHEN/TPM. Dry mouth, constipation, and paraesthesia were the most common adverse events.
“In this study, subjects with established comorbidities treated with PHEN/TPM CR showed significantly greater weight loss than placebo regardless of baseline EOSS,” Rossner and colleagues conclude.
Several authors disclosed financial ties to pharmaceutical companies, including Vivus, which manufactures phentermine/topiramate and funded the study.