my personal edition > schizophrenia > news


  E-Mail this DGNews to a colleague

DGNews

Study Shows Equivalent Efficacy and Superior Tolerability of Quetiapine Compared to Risperidone in the Treatment of Schizophrenia

MUNICH, GERMANY -- January 4, 2006 -- A study published today in the European Archives of Psychiatry and Clinical Neuroscience demonstrates that quetiapine (Seroquel) and risperidone (Risperdal) have equivalent efficacy in the treatment of patients with schizophrenia exhibiting predominately negative symptoms, however quetiapine showed superior tolerability especially with respect to extrapyramidal symptoms (EPS).1

Schizophrenia is one of the most debilitating chronic illnesses, affecting approximately 1% of the world population.2 Negative symptoms such as reduced drive and motivation, loss of ability to feel and express emotion (affective blunting), and reduced interest in taking part in activities (asociality and apathy), inability to experience pleasure (anhedonia), lack of initiative and energy (avolition) and impairment of speech (alogia) can significantly impact patient function and quality of life.

Although existing treatments for schizophrenia have been shown to address these negative symptoms, one of the key issues that impacts positive treatment outcome is patient adherence to medication, which is often influenced by side effects. This double-blind, randomized comparative study investigates efficacy and importantly the tolerability of two schizophrenia medications.

The study investigator, Michael Riedel, MD, Ludwig-Maximilian-University Munich, Germany, commented: "One of the key issues in treating patients with schizophrenia is achieving a good quality of life by balancing efficacy and tolerability of medication. Negative symptoms associated with schizophrenia are less responsive to treatment. This small, but tightly controlled pilot study shows that quetiapine and risperidone have the same efficacy in patients with schizophrenia exhibiting mainly negative symptoms, but only quetiapine shows a statistically significant effect on treating alogia and affective blunting compared to baseline. Importantly there are significant differences in the tolerability between both medications; quetiapine was superior in many tolerability parameters including EPS. To patients, a reduction in EPS really matters in terms of quality of life. Medication with less EPS therefore may help address patient compliance issues by achieving the best balance of treatment efficacy and superior tolerability."

Patients with schizophrenia presenting with predominantly negative symptoms were treated with quetiapine (mean dose 589.7 mg/day) or risperidone (mean dose 4.9 mg/day) over a 12 week period. Results were as follows:

· Patients in both treatment groups showed significant improvements in the PANSS (Positive and Negative Syndrome Scale) total, positive, negative and general psychopathology scores (P<0.01 compared to baseline).

· Patients in both treatment groups experienced significant reduction in negative symptoms as early as week one (PŁ0.01) and this improvement continued up to week 12 (PŁ0.01 for all time points).

· At week 12, both medications also achieved significant improvements on some parameters of the Assessment of Negative Symptoms (SANS) scale (quetiapine P<0.001 and risperidone P<0.01 compared to baseline), however only quetiapine demonstrated significant improvements in alogia and affective blunting compared to baseline (both P<0.001).

· Patients treated with quetiapine had a significantly lower incidence of EPS, including akathisia (restlessness and inability to remain motionless) and parkinsonism (muscle rigidity and tremor), compared to patients treated with risperidone (P=0.006).

· In addition, more patients using risperidone required anticholinergic medication to control EPS symptoms.

· Quetiapine also resulted in decrease of serum prolactin levels, whilst risperidone increased prolactin levels, which has frequently been associated with reduction in sexual drive and fertility.

Schizophrenia is the most common form of severe mental illness; approximately one in 100 people develop schizophrenia during their lifetime. There are four groups of symptoms associated with schizophrenia: 'positive', 'negative', 'cognitive', and 'affective'. Negative symptoms are associated with loss or decrease of everyday functions including drive and motivation, leading to social withdrawal.

This study was a double-blind, randomized comparative study enrolling 44 patients with schizophrenia which had mainly negative symptoms; 22 were treated with quetiapine and 22 with risperidone.

Efficacy was measured by the Positive and Negative Syndrome Scale (PANSS) score (primary endpoint), Scale for the Assessment of Negative Symptoms (SANS) and Clinical Global Impression (CGI) rating scale.

Tolerability was measured using the Simpson-Angus Scale (SAS) and various laboratory measurements.

REFERENCES:

1. Riedel M et al. Quetiapine has equivalent efficacy and superior tolerability to risperidone in the treatment of schizophrenia with predominantly negative symptoms. Eur Arch Psychiatry Clin Neurosci 2005;255(6):432-437.

2. Buchanan RW & Carpenter WT. Schizophrenia: introduction and overview. In: Sadock BJ, Sadock VA, eds. Kaplan and Sadocks Comprehensive Textbook of Psychiatry. 7th ed. Philadelphia: Lippincott Williams and Wilkins, 2000:1096–1110.


SOURCE: Ludwig-Maximilians-University of Munich

E-Mail this DGNews to a colleague

To print, use this version