The aim of the trial is to test safety, tolerability and efficacy of Propionyl-L-carnitine modified release tablets 1g/die in reducing the symptoms of the disease with respect to the proportion of patients with disease remission at the end of the 8 weeks of treatment. It will also aim to investigate capability of the treatment in the maintenance of remission after four weeks of treatment interruption; histological changes will be also evaluated and finally, improvement in the overall quality of life as measured by the Short Inflammatory Bowel Disease Questionnaire (SIBDQ) will be investigated.