OBJECTIVE(S):

Prader Willi syndrome (PWS) is a multi-symptomatic genetic disorder associated with abnormalities in the growth hormone (GH)-insulin-like-growth factor (IGF)-I axis and in the body composition. GH treatment is a registered indication in children with PWS, and improves growth rate and body composition. One pilot study in adult patients with clinical PWS has shown beneficial effects on body composition without simultaneous significant side effects. The aim of the present study is to evaluate the effects of GH treatment on body composition, muscle function and quality of life in PWS adults.

TRIAL DESIGN:

The study will be an investigator initiated and investigator sponsored multinational and multi-centre trial, including centres in Norway, Sweden and Denmark. Within each centre patients will be randomised (double blind) to one year treatment with daily injections of GH or placebo (efficacy), followed by a two year observation period on GH treatment (safety).

TRIAL POPULATION:

Twenty patients from each centre are included in the study. The patients need a genetically verified diagnosis and should be between 18 and 40 years old. Patients are excluded if GH treatment has been given within the last two years, if they have a malignancy or other serious diseases, in particular severe respiratory diseases.

ASSESSMENTS:

Effect is evaluated primarily as changes in body composition, activity of daily living and quality of life.

SAFETY: Before starting in the study all patients will be examined for tonsillary hypertrophy and sleep apnoea. Oral Glucose Tolerance Tests will be performed regularly.

TRIAL PRODUCT(S):

During the initial 4 weeks of the placebo-controlled study phase patients will be treated with sc injections of GH (Norditropin Simplexx) in the evening with doses of 0.3 mg/day respectively 0.4 mg/day if BW is below or above 100 kg. Thereafter doses will be increased to 0.6 mg/day (0.8 mg/day) and maintained fixed for 11 months. During the following 24 months open phase doses will be individually titrated.