The study will comprise two dosing periods in two different cohorts of healthy volunteers.
The investigators will begin with a single dosage period I (1 injection of 25 mg of
Risperidone for each subject); single dosage period II, different from the previous one (1
injection of 37.5 mg of Risperidone for each subject), in a second group of healthy
volunteers different from the first group will not start until after a preliminary analysis
has been made of the safety data and plasma concentration data are known for the formulation
of prolonged release Risperidone using the ISM® technology.