Incidence of Antipsychotic-Associated Side Effects: Impact of Clinician Versus Patient Ratings and Change Versus Absolute Scores

A Novel Method for Deriving Adverse Event Prevalence in Randomized Controlled Trials: Potential for Improved Understanding of Benefit-Risk Ratio and Application to Drug Labels

INTRODUCTION

Adverse event (AE) data in randomized controlled trials (RCTs) allow quantification of a drug's safety risk relative to placebo and comparison across medications. The standard US label for Food and Drug Administration-approved drugs typically lists AEs by MedDRA Preferred Term that occur at ≥ 2% in drug and with greater incidence than in placebo. We suggest that the drug label can be more informative for both patients and physicians if it includes, in addition to AE incidence (percent of subjects who reported the AE out of the total subjects in treatment), the absolute prevalence (percent of subject-days spent with an AE out of the total subject-days spent in treatment) and expected duration (days required for AE incidence to be reduced by half). We also propose a new method to analyze AEs in RCTs using drug-placebo difference in AE prevalence to improve safety signal detection.

METHODS

AE data from six RCTs in schizophrenia were analyzed (five RCTs of the dopamine D2 receptor-based antipsychotic lurasidone and one RCT of the novel trace amine-associated receptor 1 [TAAR1] agonist ulotaront). We determined incidence, absolute prevalence, and expected duration of AEs for lurasidone and ulotaront vs respective placebo. We also calculated areas under the curve of drug-placebo difference in AE prevalence and mean percent contribution of each AE to this difference.

RESULTS

A number of AEs with the same incidence had different absolute prevalence and expected duration. When accounting for these two parameters, AEs that did not appear in the 2% incidence tables of the drug label turned out to contribute substantially to drug tolerability. The percent contribution of a drug-related AE to the overall side effect burden increased the drug-placebo difference in AE prevalence, whereas the percent contribution of a placebo-related AE decreased such difference, revealing a continuum of risk between drug and placebo. AE prevalence curves for drug were generally greater than those for placebo. Ulotaront exhibited a small drug-placebo difference in AE prevalence curves due to a relatively low incidence and short duration of AEs in the ulotaront treatment arm as well as the emergence of disease-related AEs in the placebo arm.

CONCLUSION

Reporting AE absolute prevalence and expected duration for each RCT and incorporating them in the drug label is possible, is clinically relevant, and allows standardized comparison of medications. Our new metric, the drug-placebo difference in AE prevalence, facilitates signal detection in RCTs. We piloted this metric in RCTs of several neuropsychiatric indications and drugs, offering a new way to compare AE burden and tolerability among treatments using existing clinical trial information.

Validation of the Glasgow Antipsychotic Side-Effect Scale (GASS) in an Italian Sample of Patients with Stable Schizophrenia and Bipolar Spectrum Disorders

Antipsychotics are a class of psychotropic drugs that improve psychotic symptoms and reduce relapse risk. However, they may cause side effects (SE) that impact patients’ quality of life and psychosocial functioning. Therefore, there is a need for practical tools to identify them and possibly intervene. The objective of the present study was to translate into Italian the Glasgow Antipsychotic Side Effect Scale (GASS), which is suggested as the questionnaire of choice to collect SE reported by patients treated with antipsychotics. We administered the GASS and the Udvalg for Kliniske Undersøgelser (UKU) SE scale—which is considered the gold standard—to 100 stable patients with schizophrenia and bipolar spectrum disorders. We measured the structural validity, internal consistency, concurrent criterion validity, construct validity, and clinical feasibility. GASS was characterized by modest structural validity and good internal consistency. The binary correlations concerning the presence of specific symptoms investigated with the GASS and the UKU were strong or relatively strong for only half of them. The GASS total scale score was inversely related to patients’ quality of life and psychosocial functioning. The GASS is useful to briefly assess the burden of antipsychotic SE (~5 min) but is not optimal in identifying them.

Effectiveness of Traditional Chinese Medicineas as an Adjunct Therapy for Refractory Schizophrenia: A Systematic Review and Meta Analysis

Although recent studies focused on traditional Chinese medicine (TCM) for the treatment of refractory schizophrenia have reported that it may be beneficial, there is still lack of convincing evidence and critical meta-analytic work regarding its effectiveness as an adjunctive therapy. Therefore, we performed a meta-analysis to investigate the effectiveness of TCM in combination with antipsychotics for refractory schizophrenia. Fourteen articles involving 1725 patients published as of December 2016 were included which compared antipsychotic therapies to either TCM alone, or TCM as an adjunctive therapy. TCM was observed to have beneficial effects on aspects of the Positive and Negative Syndrome Scale (PANSS) including total score changes and negative score changes, as well as clinical effects estimated with PANSS or the Brief Psychiatric Rating Scale (BPRS). The changes in extrapyramidal side effects (RSESE) scores from baseline to the end of the treatment period were similar in two groups of related trials. TCM was also reported to mitigate some anti-psychotic related side-effects and overall, TCM adjuvant therapy was generally safe and well tolerated. While, the results indicated the potential utility of TCM as an alternative adjunctive therapeutic for refractory schizophrenia treatment, there remains a need for further high-quality studies.

Side effect burden of antipsychotic drugs in real life - Impact of gender and polypharmacy

BACKGROUND

Antipsychotic-associated side effects are well known and represent a significant treatment challenge. Still, few large studies have investigated the overall side effect burden of antipsychotics in real-life settings.

OBJECTIVE

To describe the occurrence of side effects and perceived burden of antipsychotics in a large naturalistic sample, taking polypharmacy and patient characteristics into account.

METHOD

Patients (n=1087) with psychotic disorders were assessed for side effects using the Udvalg for Kliniske Undersøgelser (UKU) side effect rating scale in addition to assessment of clinical and pharmacological data. Statistical analyses were performed controlling for possible confounding factors.

RESULTS

Use of antipsychotics showed significant associations to neurologic and sexual symptoms, sedation and weight gain, and >75% of antipsychotics-users reported side effects. More side effects were observed in patients using several antipsychotics (p=0.002), with increasing total dose (p=0.021) and with antipsychotics in combinations with other psychotropic drugs. Patients and investigators evaluated the side effect burden differently, particularly related to severity, gender and antipsychotics dose. Twice as many females described side effect burden as severe (p=0.004).

CONCLUSION

Patients with psychotic disorders have a high occurrence of symptoms associated with use of antipsychotics, and polypharmacy and female gender are seemingly risk factors for reporting a severe side effect burden. Due to the cross-sectional design evaluation of causality is tentative, and these findings should be further investigated in prospective studies.