SEMAFORCRANIO : Multicenter, Double-blind, Parallel, Randomized Controlled Trial of the Efficacy of Semaglutide in Hypothalamic Obesity Secondary to Craniopharyngioma in Children Aged 12 to 17 Years

Inclusion Criteria:

* Age 12 to 17 years

Treated craniopharyngioma whose last intervention was \>6 months ago and whose tumor is considered stable with :

* surgical treatmentsurgery for the solid area (non-cystic portion) of the tumor was \>6 months ago and whose tumor is considered stable
* irradiation treatment

  * Appropriate pituitary replacements (including recombinant growth hormone replacement in case of growth hormone deficiency), as assessed by the attending child's physician, according to international recommendations.
  * BMI \> + 2 SD of the French references (overweight and obesity) or BMI gain ≥ + 1 SD over the past 6 to 12 months (in the absence of overweight or obesity)
  * Failure to control weight despite strict adherence to dietary guidelines for at least six months (healthy nutrition and physical activity counseling provided by a dietician or other qualified healthcare professional)
  * For women patients with spontaneous menarche (without the use of hormone treatment with oestrogens), highly effective contraceptive methods during all study participation (and until 7 weeks after last study drug intake)
  * Subjects covered by or having the rights to medical care assurance
  * Written consent signed by the parents or legally acceptable representatives of the subject, and child participation agreement

Exclusion Criteria:

* Other weight loss treatments within 90 days before screening
* Previous surgical treatment for obesity
* Other chronic diseases
* History of pancreatitis (acute or chronic, regardless of the number of years)
* Severe psychiatric disorder (e.g., schizophrenia, bipolar disorder)
* Mental retardation
* A lifetime history of suicidal attempt
* History of NEM2 or medullary thyroid carcinoma, malignant neoplasms/carcinomas in situ, or uncontrolled thyroid disease
* Inability to understand the study
* Major problem of compliance with existing treatments (suggesting that compliance with the protocol will be insufficient)
* Any disorder, unwillingness, or inability, not covered by any of the other exclusion criteria which, in the investigator's opinion, might jeopardize the participant's safety or compliance with the protocol
* Known or suspected abuse of alcohol or recreational drugs
* History of type 1 or type 2 diabetes
* Patient with severe renal insufficiency (eGFR \< 30 mL/min/1,73m2)
* Patient with hepatic impairment (mild to severe)
* Participation in another interventional research modifying management or likely to influence the study's assessment criteria
* Pregnancy or desire of pregnancy, breast-feeding patients and parturients