TOPLINE:

Adding phentermine-topiramate extended release (ER) to a digitally enhanced lifestyle intervention results in greater weight loss at 12 months than the intervention and placebo in adults with obesity, with more than 80% of participants achieving at least 10% weight loss and reductions in lifetime risk for atherosclerotic cardiovascular disease.

METHODOLOGY:

• Clinical guidelines recommend adding antiobesity medications to lifestyle interventions to enhance weight loss; however, their effects when combined with digitally supported diet and exercise programs have not been well studied.
• Researchers conducted a 12-month randomized trial at a single tertiary academic center in the US from June 2020 to June 2022, enrolling adults aged 18-75 years with a BMI > 30 who owned a mobile device with an iPhone operating system 13 or later and had internet access.
• All participants were enrolled in a digitally enhanced lifestyle intervention incorporating in-person and telehealth modalities, a low-calorie diet, a goal of 10,000 daily steps and at least 150 minutes of weekly exercise, and regular use of digital monitoring devices.
• Participants were randomly assigned to receive either phentermine-topiramate ER at 3.75/23 mg daily for 14 days, followed by 7.5/46 mg daily, or a matching placebo, in addition to the intervention program.
• The primary outcome was weight change at 3 months; secondary outcomes included weight change at 6, 9, and 12 months; improvements in cardiometabolic risk parameters; and adverse events.

TAKEAWAY:

• In total, 80 participants (mean age, 42.2 years; 85% female; mean BMI, 42.0) were randomly assigned — 42 to the phentermine-topiramate ER group and 38 to the placebo group.
• At 3 months, participants who received phentermine-topiramate ER achieved greater mean weight loss than those receiving placebo (10.82 kg vs 4.04 kg; mean difference, -6.78 kg; P = .002). At 12 months, weight loss remained significantly greater in the phentermine-topiramate ER group (15.32 kg vs 5.85 kg; mean difference, -9.48 kg; P < .001).
• At 12 months, participants in the phentermine-topiramate ER group were more likely than those in the placebo group to achieve weight loss of at least 5% (100% vs 42%), 10% (83% vs 11%), and 15% (43% vs 5%; P ≤ .001 for all comparisons).
• Combination therapy was associated with a greater reduction in estimated lifetime risk for atherosclerotic cardiovascular disease than placebo (difference, -6.78%; P = .004), along with greater reductions in waist circumference, BMI, and diastolic blood pressure.
• Adverse events occurred more frequently in the phentermine-topiramate ER group than in the placebo group (26% vs 8%), with paresthesias, dry mouth, and dysgeusia reported most commonly.

IN PRACTICE:

“Further studies are warranted to determine whether a [digitally enhanced lifestyle intervention] provides an additive or synergistic benefit when combined with pharmacologic weight loss therapies,” the authors of the study wrote.

SOURCE:

The study was led by Alejandro Campos, Precision Medicine for Obesity Program, Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, Rochester, Minnesota. It was published online in Obesity.

LIMITATIONS:

The sample size was modest. Participants’ technology literacy affected compliance with digital device use, and the lack of integrated calorie tracking within the smartphone application limited assessment of dietary adherence. The study population was predominantly White and female, which may limit generalizability.

DISCLOSURES:

The study was supported by VIVUS LLC. One author and the Mayo Clinic reported holding equity in Phenomix Sciences, Inc., and being inventors of intellectual property licensed to Phenomix Sciences, Inc. One author reported serving as a consultant for various companies. Three authors reported being employees of Vivus LLC.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.