In a study comparing the time it takes for someone with schizophrenia to relapse (go off of treatment), risperidone (Risperdal) long-acting injection (RLAI) was found to offer a longer time before relapse than another commonly prescribed anti-psychotic medication, quetiapine (Seroquel).
Data presented from the study showed that the mean time to relapse for patients treated with RLAI was statistically longer than those treated with quetiapine (607 days RLAI versus 533 days with quetiapine, p<0.0001).
The study did not measure the drug’s efficacy on any clinician-rated or patient-rated scales.
For patients living with schizophrenia, relapse may be associated with an increased risk of hospitalization and can have a major negative impact on their quality of life.
Non-compliance or partial compliance remain key barriers in the management of schizophrenia and are often significant contributing factors in relapse. Patients experiencing numerous relapses are at high risk of never regaining previous levels of functioning, therefore, preventing relapse is paramount in order to improve the long-term outcome for people living with the condition.
However, preventing relapse says nothing about whether a drug is effectively managing a patient’s symptoms. A longer time to relapse could simply indicate the drug is better tolerated, but not necessarily more effective at controlling the complex symptoms common in people with schizophrenia.
The study, a 24-month open-label comparative study with no placebo control group, investigated the effect of treatment with RLAI or oral quetiapine on relapse prevention and efficacy maintenance as measured by time to relapse.
710 patients were randomized to receive either RLAI (N=355 (mean dose 32.75 mg)) or oral quetiapine (N=355 (mean dose 396.75 mg)).
The data indicate that not only did RLAI significantly extend time to relapse versus quetiapine (607 days RLAI versus 533 days with quetiapine, p<0.0001), fewer patients in the RLAI treatment arm relapsed over the 24-month trial period compared with oral quetiapine (16.5% and 31.3% respectively). In addition, the treatment completion rates favored RLAI (51.7%) over oral quetiapine (38%) (p <0.0004).1
Safety results demonstrated that RLAI had a comparable safety and tolerability profile to quetiapine, with the majority of both treatment groups reporting treatment-emergent adverse events (67.5% for the RLAI group, 68.5% for the quetiapine group).
However, patients taking the RLAI treatment were over five times more likely to have a sexual dysfunction, such as impotence, ejaculatory failure, or loss of libido as compared to patients taking quetiapine.
Weight gain was observed in both treatment arms with no statistically significant differences in changes in body weight or BMI versus baseline (7% weight gain for RLAI versus 6.2% for quetiapine).
Drowsiness was reported in 1.8% of patients treated with RLAI compared to 11.3% with quetiapine.
Reasons for withdrawing from the study, other than relapse, were equivalent in both treatment groups.
The results were presented at the annual meeting of the American Psychiatric Association.
Source: Compiled from a press release from Janssen-Cilag