Topiramate and Severe Obesity

Childhood obesity remains through adulthood in main cases, and is associated with an early increase of cardiovascular risk and an excess mortality in young adults due to stroke and cancer.

Bariatric surgery is very rare in France for children and can cause severe complications. Long term effects are still unknown.

Topiramate is already use in thousands of children in neurology, its effects are already well known, and no lethal complication is reported.

The hypothesis is that Topiramate associated with standard treatment of obesity is more effective than standard treatment alone.

This will be a 4.5-years, randomized, double-blind, placebo-controlled, clinical trial of topiramate (9 months) vs placebo (9months) for Body Mass Index reduction in 160 adolescents (ages 9-17 years old) with severe obesity.

The main objective is to evaluate the efficacy of Topiramate on the decrease of Body Mass Index compared to placebo at 9 months.

The secondary objectives are to evaluate:

• the decrease of Body Mass Index Z-score
• the tolerance of Topiramate
• the effectiveness of Topiramate on weight decrease and decrease of Body Mass Index and Body Mass Index Z-score at 1, 3 ,4 and 6 months
• the effectiveness of Topiramate on eating behaviour, physical activity, calculated with validated questionnaires and scales at 6 and 9 months
• the pharmacokinetic of Topiramate in obese children and adolescents

Inclusion criteria

• 9-17 years old
• Body Mass Index Z-score ≥ 4 SD of French reference
• Weight at enrolment ≥ 50 kg
• Therapeutic failure > 6 months
• For girls of childbearing age, willing to have an acceptable method of contraception (no estrogens plus progestin)
• Negative pregnancy test for girls of childbearing age
• Agreeing to participate upon written informed consent
• Appropriate understanding of the study

Exclusion criteria

• Syndromic or secondary obesity
• Major neurological or psychiatric disorder
• Current or history of suicidal thought/attempts
• Current or history of breakdown
• Previous bariatric surgery
• Severe hypercapnia
• Renal dysfunction
• Deformity in the urinary tract or solitary kidney
• History of renal lithiasis or glaucoma
• Poorly controlled diabetic children or adolescents (HbA1c >10%) and diabetic patients treated with Metformine and/or glibenclamide
• Hepatic dysfunction
• Bicarbonate ≤16 mmol/L
• Known hypersensitivity to the active substance or to one of the excipients
• Intolerance to saccharose
• Enrolment in another therapeutic study
• High probability to fail to comply with treatment
• Females: Pregnant, planning to become pregnant
• No signature on consent form
• Uncovered by the French National health Insurance system (Sécurité sociale)