Excessive weight gain is a cardinal feature of Prader-Willi syndrome (PWS) for which there is
presently no effective treatment. It is caused by increased appetite, decreased perception of
satiety and obsessive and compulsive behaviour towards food. Ghrelin is a powerful
appetite-stimulating hormone. Patients with PWS have markedly elevated ghrelin levels,
suggesting that it may be responsible for the increased food intake. The goal of the study is
to determine whether treatment with somatostatin (Sandostatin), a hormone that inhibits
ghrelin, is an effective treatment for the prevention and treatment of weight excess in
patients with PWS.