Depot Risperidone for Schizophrenia

A Cochrane review [Abstract] 1 included 12 studies with a total of 5723 subjects with schizophrenia. The following comparison treatments were used.

• Risperidone depot vs. placebo: Outcomes of relapse and improvement in mental state were neither measured or reported. In terms of other primary outcomes, more people receiving placebo left the study early by 12 weeks (RR 0.74 95% CI 0.63 to 0.88; 1 RCT, n=400), experienced severe adverse events in short term (RR 0.59 95% CI 0.38 to 0.93; 1 RCT, n=400). There was however, no difference in levels of weight gain between groups (RR 2.11 95% CI 0.48 to 9.18; 1 RCT, n=400).
• Risperidone depot vs. general oral antipsychotics: The outcome of improvement in mental state was reported. Most primary outcomes of interest showed no difference between treatment groups. However, more people receiving depot risperidone experienced nervous system disorders (RR 1.34 95% CI 1.13 to 1.58; 1 RCT, n=369).
• Risperidone depot vs. oral risperidone:Data for relapse and severe adverse events were not reported. Main results showed no differences between treatment groups with equivocal data for change in mental state, numbers leaving the study early, any extrapyramidal symptoms, weight increase and prolactin-related adverse events (2 studies, n=690).
• Risperidone depot vs. oral quetiapine:Relapse rates and improvement in mental state were not reported. Fewer people receiving risperidone depot left the study early (RR 0.84 95% CI 0.74 to 0.95; 1 RCT, n=666). Experience of serious adverse events was similar between groups, but more people receiving depot risperidone experienced extrapyramidal symptoms (EPS) (RR 1.83 95% CI 1.07 to 3.15; 1 RCT, n=666), had greater weight gain (RR 1.25 95% CI 0.25 to 2.25;1 RCT, n=666) and more prolactin-related adverse events (RR 3.07 95% CI 1.13 to 8.36; 1 RCT, n=666).
• Risperidone depot vs. oral aripiprazole:Relapse rates, mental state using PANSS, leaving the study early, serious adverse events and weight increase were similar between groups. However more people receiving depot risperidone experienced prolactin-related adverse events compared to those receiving oral aripiprazole (RR 9.91 95% CI 2.78 to 35.29; 2 RCTs, n=729).
• Risperidone depot vs. oral olanzapine:Relapse rates were not reported in any of the studies. Improvement in mental state using PANSS and instances of severe adverse events were similar between groups. More people receiving depot risperidone left the study early than those receiving oral olanzapine (RR 1.32 95% CI 1.10 to 1.58; 1 RCT, n=618) with those receiving risperidone depot also experiencing more EPS (RR 1.67 95% CI 1.19 to 2.36; 1 RCT, n=547). However, more people receiving oral olanzapine experienced weight increase (RR 0.56 95% CI 0.42 to 0.75; 1 RCT, n=547).
• Risperidone depot vs. atypical depot antipsychotics: Especifically paliperidone palmitate was studied.Relapse rates were not reported and rates of response using PANSS, weight increase, prolactin-related adverse events and glucose-related adverse events were similar between groups. Fewer people left the study early due to lack of efficacy from the risperidone depot group (RR 0.60 95% CI 0.45 to 0.81; 1 RCT, n=749), but more people receiving depot risperidone required use of EPS medication (RR 1.46 95% CI 1.18 to 1.8; 2 RCTs, n=1666).
• Risperidone depot vs. typical depot antipsychotics:Outcomes of relapse, severe adverse events or movement disorders were not reported. Outcomes relating to improvement in mental state demonstrated no difference between groups. However, more people receiving depot risperidone compared to other typical depots left the study early (RR 3.05 95% CI 1.12 to 8.31; 1 RCT, n=62).

Comment: The quality of evidence is downgraded by study quality (high drop-out rate, imcomplete blinding, reporting bias) and by indirectness (important outcomes missing).

References

• Sampson S, Hosalli P, Furtado VA et al. Risperidone (depot) for schizophrenia. Cochrane Database Syst Rev 2016;4():CD004161. [PubMed]