Switching and combining antipsychotics

The dilemma of polypharmacy in psychosis: is it worth combining partial and full dopamine modulation?

Antipsychotic polypharmacy in psychotic disorders is widespread despite international guidelines favoring monotherapy. Previous evidence indicates the utility of low-dose partial dopamine agonist (PDAs) add-ons to mitigate antipsychotic-induced metabolic adverse effects or hyperprolactinemia. However, clinicians are often concerned about using PDAs combined with high-potency, full dopaminergic antagonists (FDAs) due to the risk of psychosis relapse. We, therefore, conducted a literature review to find studies investigating the effects of combined treatment with PDAs (i.e. aripiprazole, cariprazine and brexpiprazole) and FDAs having a strong D 2 receptor binding affinity. Twenty studies examining the combination aripiprazole - high-potency FDAs were included, while no study was available on combinations with cariprazine or brexpiprazole. Studies reporting clinical improvement suggested that this may require a relatively long time (~11 weeks), while studies that found symptom worsening observed this happening in a shorter timeframe (~3 weeks). Patients with longer illness duration who received add-on aripiprazole on ongoing FDA monotherapy may be at greater risk for symptomatologic worsening. Especially in these cases, close clinical monitoring is therefore recommended during the first few weeks of combined treatment. These indications may be beneficial to psychiatrists who consider using this treatment strategy. Well-powered randomized clinical trials are needed to derive more solid clinical recommendations.

Antipsychotic utilization trajectories three years after initiating or reinitiating treatment of schizophrenia: A state sequence analysis approach

OBJECTIVE

This study aims to describe the utilization patterns of antipsychotic (AP) medication in patients with schizophrenia (SCZ), three years after initiating or reinitiating a given AP.

METHODS

Based on medico-administrative information on patients living in Quebec (Canada), this retrospective cohort study included 6444 patients with a previous diagnosis of SCZ initiating or reinitiating AP medication between January 1, 2012, and December 31, 2014, with continuous coverage by public drug insurance. For each day of follow-up (1092 days), patient was either exposed to one of the chosen categories of APs, or to none. This patient's sequence of AP exposure overtime has been referred to as the "antipsychotic utilization trajectory". These trajectories were analyzed using a State Sequence Analysis, an innovative approach which provides useful visual information on the continuation and discontinuation patterns of use over time.

RESULTS

Clozapine and long-acting injectable second-generation APs had the best continuation and discontinuation patterns over 3 years among all other groups, including less switching of APs, while oral first-generation APs had the poorest patterns. These findings were comparable among incident and non-incident cohorts. Oral second-generation antipsychotics, excluding clozapine, had a poorer continuation and discontinuation pattern than long-acting injectable antipsychotics.

CONCLUSION

State Sequence Analysis provides a clear representation of treatment adherence in comparison with dichotomous indicators of adherence or discontinuation. Consequently, this innovative method has shed light on the impact of the AP chosen to initiate or reinitiate treatment in SCZ, which has been identified as a key factor for long-term treatment continuation and discontinuation.

Successful switching of patients with acute schizophrenia from another antipsychotic to brexpiprazole: comparison of clinicians' choice of cross-titration schedules in a post hoc analysis of a randomized, double-blind, maintenance treatment study

OBJECTIVE

To compare the tolerability and efficacy of different antipsychotic cross-titration schedules, using data from a brexpiprazole study (Equator; NCT01668797).

METHODS

Patients with schizophrenia were cross-titrated from other antipsychotics to brexpiprazole monotherapy in a 1-4 week open-label conversion phase, then entered a single-blind brexpiprazole treatment phase. Patients were stratified into four "conversion groups," according to the amount of time spent in the conversion phase. Discontinuation rates, treatment-emergent adverse events (TEAEs), and efficacy (Positive and Negative Syndrome Scale [PANSS]) were compared between conversion groups.

RESULTS

Of the 404 patients treated with brexpiprazole, the majority (72.0%) spent 22-33 days in the conversion phase. Discontinuation rates due to lack of efficacy or adverse events were low in all conversion groups. Of the 292 patients who successfully switched and completed 8 weeks of brexpiprazole treatment, most were converted to brexpiprazole over 22-33 days (80.1%), and fewer were converted over 1-7 days (2.4%), 8-14 days (6.5%), or 15-21 days (11.0%). The incidence of TEAEs over 8 weeks was lower among those converted over 22-33 days (44.4%) than in other conversion groups (62.5-84.2%), although low patient numbers with shorter conversion times limit the generalizability of this finding. Each conversion group showed comparable improvement in PANSS total score from baseline.

CONCLUSION

The majority of patients were cross-titrated to brexpiprazole over a period of 22-33 days, by investigators' choice. Additional data on shorter conversions may help clinicians to choose a switching paradigm that best meets their patients' needs.

Switching to antipsychotic monotherapy vs. staying on antipsychotic polypharmacy in schizophrenia: A systematic review and meta-analysis

BACKGROUND

While recent meta-analyses have reported the superiority of antipsychotic polypharmacy (APP) over antipsychotic monotherapy (APM) in schizophrenia, switching to APM can be beneficial in terms of side effects. To determine whether patients receiving APP should switch to APM or stay on APP, we conducted a systematic review and meta-analysis.

METHODS

Randomized controlled trials (RCTs) examining a switch from APP to APM vs. staying on APP were systematically selected from a previous meta-analysis comparing APP with APM in patients with schizophrenia. In addition, we conducted an updated systematic literature search using MEDLINE, Embase, and Cochrane Central Register of Controlled Trials. Data on study discontinuation, relapse, psychopathology, neurocognition, extrapyramidal symptoms, and body weight/body mass index (BMI) were extracted and synthesized.

RESULTS

A total of 6 RCTs involving 341 patients were included. All studies examined a switch from 2 antipsychotic agents to a single agent. Clozapine-treated patients were included in 3 studies. There was a significant difference in study discontinuation due to all causes in favor of staying on APP (N = 6, n = 341, RR = 2.28, 95% CI = 1.50-3.46, P < 0.001). There were no significant differences in relapse, any psychopathology, neurocognition, extrapyramidal symptoms, or body weight/BMI between the 2 groups. The quality of evidence was low to very low.

CONCLUSIONS

The findings suggest that clinicians should closely monitor patient condition when switching to APM after receiving 2 antipsychotics. Given the low to very low overall quality of the evidence, the findings should be considered preliminary and inconclusive.

Immediate vs Gradual Discontinuation in Antipsychotic Switching: A Systematic Review and Meta-analysis

Background

Antipsychotic switching is routine in clinical practice, although it remains unclear which is the preferable switching method: immediate discontinuation of the current antipsychotic or a gradual tapering approach. The first strategy has been implicated in rebound/withdrawal symptoms and emergence/exacerbation of symptoms, whereas the gradual approach is thought to pose a risk of additive or synergistic side effects if employed in the context of a crossover approach.

Methods

MEDLINE, Embase, and Cochrane Central Register of Controlled Trials were systematically searched. Randomized controlled trials examining immediate vs gradual antipsychotic discontinuation in antipsychotic switching in patients with schizophrenia and/or schizoaffective disorder were selected. Data on clinical outcomes, including study discontinuation, psychopathology, extrapyramidal symptoms, and treatment-emergent adverse events, were extracted.

Results

A total of 9 studies involving 1416 patients that met eligibility criteria were included in the meta-analysis. No significant differences in any clinical outcomes were found between the 2 approaches (all Ps > .05). Sensitivity analyses revealed that the findings remained unchanged in the studies where switching to aripiprazole was performed or where immediate initiation of the next antipsychotic was adopted, while some significant differences were observed in switching to olanzapine or ziprasidone.

Conclusions

These findings indicate that either immediate or gradual discontinuation of the current antipsychotic medication represents a viable treatment option. Clinicians are advised to choose an antipsychotic switching strategy according to individual patient needs. This said, immediate discontinuation may be advantageous both for simplicity and because a stalled cross-titration process in antipsychotic switching could end up in antipsychotic polypharmacy.

Antipsychotic switching in schizoaffective disorder: A systematic review

OBJECTIVES

To systematically review the evidence about the switching of antipsychotics in SZA in acute and maintenance treatment.

METHODS

A systematic review following the PRISMA statement identifying studies specifically conducted on, or including, SZA patients.

RESULTS

One analysis considered uniquely a SZA population, 13 more studies including an adequate SZA subsample were considered. Most of the studies were aimed at switching antipsychotic treatments to improve tolerability issues. Despite the absolute lack of trials specifically conducted on SZA populations, we found limited evidence on the use of aripiprazole, lurasidone, and, to a lesser extent, risperidone and ziprasidone as possible agents to substitute previous treatments whereas efficacy or, more frequently, tolerability issues arise. Evidence supports also the switch to risperidone long-acting injectable when the adherence to oral treatment may be a concern.

CONCLUSIONS

Antipsychotic switching in SZA is a neglected topic that would need better profiling. Clinicians should keep in mind the receptor binding characteristics of drugs in order to optimize transitions. Evidence supports the switch to aripiprazole and lurasidone, less strongly to risperidone and ziprasidone. The switch to risperidone long-acting injectable is supported, especially in patients with limited treatment adherence to oral therapy.