Prospective studies, risperidone

In a double-blind, multicenter, prospective study, Csernansky et al. (2002) showed that among patients with clinically stable chronic schizophrenia or schizoaffective disorder the risk of relapse was significantly lower with risperidone than with haloperidol (34% vs. 60%, P < 0.001). The means of daily doses of risperidone ( 4.9mg) and haloperidol (11.7mg) were similar to those used in clinical practice (Csernansky et al.y 2002). The reduced risk of relapse found with risperidone could be due to its superior efficacy, better tolerability or both (Csernansky et al.y 2002). 

A number of patients have been exposed to clozapine for several years and TD has not developed. Studies have also investigated patients with TD who were switched to clozapine for periods of 3 weeks to 6 months (461, 462, 463 and 464). Some appeared to improve, but these findings are difficult to interpret because control groups would be needed to demonstrate conclusively that clozapine does not cause TD. Theoretically, if clozapine does not cause acute EPS, then it should not cause TD. Other novel agents such as risperidone, olanzapine, quetiapine, and ziprasidone await longer term exposure to assess their propensity to induce TD. Thus, we agree with Casey, who wrote it is possible that compounds associated with a low rate of EPS may also produce less TD, but prospective studies are needed to confirm this premise (465). 

The effect of citalopram on plasma concentrations of risperidone has been prospectively studied in 15 patients with schizophrenia (32). The addition of citalopram did not alter plasma risperidone concentrations. 

The aims of a prospective study in 113 consecutively hospitalized young patients (mean age 22 years) were to determine whether the severity of obsessive-compulsive symptoms differs during treatment with olanzapine or risperidone and to establish whether the duration of neuroleptic treatment is related to the severity of obsessive-compulsive symptoms (152). At baseline and week 6 assessments, obsessive-compulsive symptoms were found in 32 of 106 evaluable cases and 16 met DSM-IV criteria for obsessive-compulsive disorder, but there were no differences in patients taking olanzapine or risperidone. However, the severity of obsessive-compulsive symptoms was associated with the duration of treatment with olanzapine. 

In an 8-week open prospective study of risperidone in 20 patients, mean age 34 (range 19-53) years, adverse effects included giddiness (n = 3), headache (n = 2), and agitation (n = 2) one woman reported galactorrhea and another developed obsessive-compulsive symptoms 16 of 20 patients were taking antiparkinsonian drugs before the study, compared with 12 patients at the end (10). 

Olanzapine (n — 172) has been compared with risperidone (n — 167) in an international, multicenter, double-blind, parallel-group, 28-week prospective study in 339 patients who met DSM-IV criteria for schizophrenia, schizophreniform disorder, or schizoaffective disorder (81). Both olanzapine (starting dosage 15 mg/ day) and risperidone (starting dosage 1 mg bd) were effective in the management of psychotic symptoms. 

Thomas SH, Drici MD, Hall GC, Crocq MA, Everitt B, Lader MH, Le Jeunne C, Naber D, Priori S, Sturkenboom M, Thibaut F, Peuskens J, Mittoux A, Tanghpj P, Toumi M, Moore ND, Mann RD. Safety of sertin-dole versus risperidone in schizophrenia principal results of the sertindole cohort prospective study (SCoP). Acta Psychiatr Scand 2010 122 345-55. 

McDougle, C.J., Holmes, J.P., Bronson, M.R., Anderson, G.M., Volkmar, F.R., Price, L.H., and Cohen, D.J. (1997) Risperidone treatment of children and adolescents with pervasive developmental disorders a prospective, open-label study. / Am Acad Child Adolesc Psychiatry 36 685-693. 

A prospective 6-month open study, promoted by Lilly, the market authorization holder of olanzapine, has been conducted, in which olanzapine (n = 2128), risperidone (n = 417), and haloperidol (n = 112) were compared... 

Sacristan JA, Gomez JC, Montejo AL, Vieta E, Gregor KJ. Doses of olanzapine, risperidone, and haloperidol used in clinical practice results of a prospective phar-macoepidemiologic study. EFESO Study Group. Estudio Farmacoepidemiologico en la Esquizofrenia con Olanzapina. Clin Ther 2000 22(5) 583-99. 

Comparative studies The SCoP study was a prospective, randomized, partially blinded, active-controlled, multinational trial, designed to assess the safety of sertindole in the treatment of schizophrenia under normal conditions of use risperidone was the comparator. Results are now emerging. For instance, sertindole did not increase allcause mortality, but cardiac mortality was higher and suicide attempts possibly lower with sertindole [147. The study comprised 9858 selected patients with schizophrenia, and after 14147 person-years the major findings were (i) no statistically significant difference between sertindole ( = 4905) and risperidone (n = 4904) in the two co-primary outcomes, i.e. all-cause mortality (sertindole 64 deaths, risperidone 61 deaths HR=1.12 90% Cl = 0.83, 1.5) and cardiac events... 

Choure BK, Gosavi D, Nanotkar S (2014) Comparative cardiovascular safety of risperidone and olanzapine, based on electrocardiographic parameters and blood pressure a prospective open label observational study. Indian J Pharmacol 46 493 97... 

Ishitobi M, Kosaka H, Takahashi T, Yatuga C, Asano M, Tanaka Y, et al. Effectiveness and tolerability of switching to aripiprazole from risperidone in subjects with autism spectrum disorders a prospective open-label study. Clin Neiuopharmacol 2013 36(5) 151-6. 

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