Efficacy and safety of topiramate in the treatment of obese subjects with essential hypertension.

The effect of topiramate on weight and blood pressure (BP) was examined in a randomized, placebo-controlled trial in obese subjects who had hypertension. After a 4-week, placebo, run-in period, 531 obese subjects (body mass index 27 to 50 kg/m(2)) who had established hypertension were randomly assigned to placebo or 96 or 192 mg/day of topiramate. All subjects received a standardized diet, exercise advice, and behavioral modification from run-in through study end. Initially scheduled for 60 weeks on medication, the sponsor ended the study early to develop a new controlled-release formulation. As a consequence, efficacy was assessed within a predefined modified intent-to-treat population (subjects who enrolled early enough to potentially complete 28 weeks on medication). The placebo and 96- and 192-mg groups had respective weight losses of 1.9%, 5.9%, and 6.5% from baseline (p <0.001 for each comparison with placebo) and decreases in diastolic BP of 2.1, 5.5, and 6.3 mm Hg (p <0.015 vs placebo). Systolic BP was decreased by 8.6 and 9.7 mm Hg in the 96- and 192-mg groups and 4.9 mm Hg in the placebo group (p = NS). Compared with placebo, the topiramate groups had larger proportions of subjects whose weight decreased by > or =5% and 10%, whose diastolic BP decreased by > or =5 and 10 mm Hg, and who achieved normalization of BP (BP <130/85 mm Hg). Adverse events included paresthesia, fatigue, taste perversion, loss of appetite, and difficulty with concentration and attention. In conclusion, topiramate produced clinically relevant effects in reducing body weight and BP, with generally mild to moderate adverse effects.

Topiramate: long-term maintenance of weight loss induced by a low-calorie diet in obese subjects.

OBJECTIVE: To examine the safety and efficacy of topiramate (TPM) for maintaining weight following a low-calorie diet. RESEARCH METHODS AND PROCEDURES: Obese subjects (30 < or = BMI < 50 kg/m(2)) 18 to 75 years old received a low-calorie diet for 8 weeks. Those who lost > or =8% of their initial weight received TPM (96 or 192 mg/d) or placebo; all were on a lifestyle modification plan. Sixty weeks of medication were planned. Sponsor ended study early to develop a new controlled-release formulation with the potential to enhance tolerability and simplify dosing in this patient population. Efficacy was analyzed in subjects who completed 44 weeks of treatment before study termination. RESULTS: Of the 701 subjects enrolled, 80% lost > or =8% of their initial body weight and were randomized; 293 were analyzed for efficacy. Most withdrawals were due to premature termination of the study. Subjects receiving TPM lost 15.4% (96 mg/d) and 16.5% (192 mg/d) of their enrollment weight by week 44, compared with 8.9% in the placebo group (p < 0.001). Subjects on TPM continued to lose weight after the run-in, whereas those on placebo regained weight. Significantly more TPM subjects lost 5%, 10%, or 15% of their randomization weight than placebo. Most adverse events were related to the central nervous system. DISCUSSION: During a treatment period of 44 weeks, TPM was generally well tolerated, and subjects maintained weight loss initially achieved by a low-calorie diet-and produced additional clinically significant weight loss beyond that achieved by a low-calorie diet.

A 6-month randomized, placebo-controlled, dose-ranging trial of topiramate for weight loss in obesity.

OBJECTIVE: To evaluate the efficacy and safety of topiramate (TPM) for weight loss in healthy obese subjects. RESEARCH METHODS AND PROCEDURES: A randomized, double-blind, placebo-controlled, dose-ranging trial was conducted. Three hundred eighty-five subjects, 18 and 75 years of age, were randomized to receive either placebo or TPM at 64, 96, 192, or 384 mg daily. Dosing began at 16 mg once daily. In week 2, the dose was increased to 16 mg twice daily. Thereafter, the dose was raised every week by 32 mg/d (16 mg twice daily) until subjects reached their target dose. Twenty-four weeks after beginning treatment, all subjects were tapered off treatment by a dose reduction of 50% per week. All participants received the same lifestyle program. RESULTS: Mean percent weight loss from baseline to week 24 was -2.6% in placebo-treated patients vs. -5.0%, -4.8%, -6.3%, and -6.3% in the 64, 96, 192, and 384 mg/d TPM groups, respectively. Greater percentages of TPM-treated patients lost at least 5% or 10% of body weight compared with placebo. The most frequent adverse events were related to the central or peripheral nervous system, including paresthesia, somnolence, and difficulty with memory, concentration, and attention. Most events were dose-related, occurred early in treatment, and usually resolved spontaneously; only 21% receiving TPM withdrew due to adverse events compared with 11% on placebo. DISCUSSION: TPM produced significantly greater weight loss than placebo at all doses.