In order to test these hypotheses, the following primary outcome variables will be derived from the primary outcome measures: difference between semantic verbal fluency test scores at baseline and and 1 and 30 days after completion of the treatment period (dSF1, dSF30), difference between picture naming test scores at baseline and 1 and 30 days after completion of the treatment period (dPN1, dPN30), difference between Token test scores at baseline and 1 and 30 days after completion of the treatment period (dTT1, dTT30) and a cumulative number of AE and SAE during 10 days of therapy (AE1) and during the 30 days follow-up period (AE30).