Challenging the need for sustained blockade of dopamine D₂ receptor estimated from antipsychotic plasma levels in the maintenance treatment of schizophrenia: A single-blind, randomized, controlled study

Guided antipsychotic reduction to reach minimum effective dose (GARMED) in patients with remitted psychosis: a 2-year randomized controlled trial with a naturalistic cohort

BACKGROUND

Patients with remitted psychosis face a dilemma between the wish to discontinue antipsychotics and the risk of relapse. We test if an operationalized guided-dose-reduction algorithm can help reach a lower effective dose without increased risks of relapse.

METHODS

A 2-year open-label randomized prospective comparative cohort trial from Aug 2017 to Sep 2022. Patients with a history of schizophrenia-related psychotic disorders under stable medications and symptoms were eligible, randomized 2:1 into guided dose reduction group (GDR) v. maintenance treatment group (MT1), together with a group of naturalistic maintenance controls (MT2). We observed if the relapse rates would be different between 3 groups, to what extent the dose could be reduced, and if GDR patients could have improved functioning and quality of life.

RESULTS

A total of 96 patients, comprised 51, 24, and 21 patients in GDR, MT1, and MT2 groups, respectively. During follow-up, 14 patients (14.6%) relapsed, including 6, 4, and 4 from GDR, MT1, and MT2, statistically no difference between groups. In total, 74.5% of GDR patients could stay well under a lower dose, including 18 patients (35.3%) conducting 4 consecutive dose-tapering and staying well after reducing 58.5% of their baseline dose. The GDR group exhibited improved clinical outcomes and endorsed better quality of life.

CONCLUSIONS

GDR is a feasible approach as the majority of patients had a chance to taper antipsychotics to certain extents. Still, 25.5% of GDR patients could not successfully decrease any dose, including 11.8% experienced relapse, a risk comparable to their maintenance counterparts.

Dose-tapering trajectories in patients with remitted psychosis undergoing guided antipsychotic reduction to reach minimum effective dose

BACKGROUND

Patients with remitted psychosis wish to reduce antipsychotic doses yet facing increased risks of relapse. Examining dose-tapering processes may provide insights to re-evaluate the risk-to-benefit balance. We aimed to depict and subgroup tapering trajectories, and explore factors associated with different dose-reduction patterns.

METHODS

A 2-year open-label randomized prospective comparative trial from August 2017 to September 2022 in Taiwan. Patients with a history of schizophrenia-related psychotic disorders under stable medications and symptoms were eligible, randomizing a proportion to conduct guided dose reduction. We depicted the trajectories of individual patients and named subgroups based on dose-tapering patterns. Predictors of baseline characteristics for designated subgroups were examined by logistic regression analysis; changes in outcomes were compared by paired t-test.

RESULTS

Fifty-one patients undergoing guided dose reduction, 18 (35.3%) reduced 4 steps consecutively (sequential reducers, SR), 14 (27.5%) reduced 1 to 3 steps (modest reducers, MR), 3 (5.9%) re-escalated to previous level (alert reducers, AR), 7 (13.7%) returned to baseline level (baseline returners, BR), 6 (11.7%) relapsed (failed reducers, FR) and 3 (5.9%) withdrew without relapse (early exits, EE). Patients with a history of relapse assumed a conservative dose-tapering pace; only the SR subgroup exhibited significant improvements in functioning and quality of life while failing to identify variables for predicting who would become SR or FR.

CONCLUSIONS

Guided dose reduction comprises dynamic processes with differences between individual trajectories. The proposed naming of dose-tapering patterns/subgroups provides a framework depicting patients undergoing dose-tapering. Longer-term observation and more flexible tapering approaches are anticipated to reveal favorable outcomes.

Protocol of guided antipsychotic reduction to reach minimum effective dose (GARMED) in patients with remitted psychosis based on pragmatic design

AIMS

Patients with psychosis intend to discontinue antipsychotic treatment for various reasons. As antipsychotic discontinuation involves a high risk of relapse, maintenance treatment is recommended by mainstream opinion even when remission is attained. To optimize the risk-to-benefit ratio of long-term antipsychotic treatment, we proposed an operationalized guided dose-reduction algorithm to serve as an intermediate approach as to achieve the lowest effective antipsychotic dose and better functioning for patients with remitted psychosis.

METHODS

Outpatients with a history of schizophrenia-related psychotic disorders currently under stable medications and symptoms are eligible to register in this protocol. Patients intending for dose reduction are randomized into 2:1, guided dose reduction group (GDR) versus maintenance treatment group (MTG1). Eligible patients who do not intend to reduce antipsychotics serve as naturalistic maintenance controls (MTG2). The GDR patients reduce no more than 25% of their baseline antipsychotic dose, with at least a 6-month stabilization period before reducing another 25% of their last dose. The timing of the next dose reduction will be determined by shared decision-making with the patient. Following a dose reduction, the patients will receive three consecutive monthly monitoring; otherwise, they receive treatment as usual.

DISCUSSION

By employing this pragmatic-based protocol, patients are empowered to evaluate their readiness for next dose reduction attempt. We would like to test in real-world situations if stable patients can reduce antipsychotics not at the expense of an increased risk of relapse, so as to optimize the balance between risk-to-benefit ratios of long-term antipsychotic treatment.

Reversibility of Antipsychotic-Induced Weight Gain: A Systematic Review and Meta-Analysis

BACKGROUND AND AIMS

Weight gain is a major adverse effect of antipsychotic medication, negatively affecting physical and mental well-being. The objective of this study was to explore if dose reduction, discontinuation, switch to a partial agonist, or switch from polypharmacy to monotherapy will lead to weight loss.

METHODS

Controlled and uncontrolled studies reporting the effects of discontinuation, dose reduction, switch to a partial agonist, or switch from polypharmacy to monotherapy on weight were included. Primary outcome was difference in weight compared to maintenance groups based on controlled studies. Secondary outcome was change in weight from initiation of one of the included interventions until follow-up in a pre-post analysis.

RESULTS

We identified 40 randomized controlled trials and 15 uncontrolled studies including 12,279 individuals. The effect of the interventions, i.e. dose reduction, drug discontinuation, or switch to a partial agonis, reduced the weight with 1.5 kg (95% CI -2.03 to -0.98; P < 0.001) compared to maintenance treatment. The weight change from pre to post was a reduction of 1.13 kg (95% CI -1.36 to -0.90; P < 0.001).

CONCLUSION

We found a significant but small reduction in weight, suggesting that antipsychotic-induced weight gain can be reversed to some degree. Only a few studies were designed to address the question as primary outcome, which limits the generalizability of our findings.

Challenging the Minimum Effective Antipsychotic Dose During Maintenance: Implications From 10-Year Follow-Up of First Episode Psychosis

Background: Contradictory messages regarding the necessity of long-term antipsychotic treatment after first episode psychosis arouse deliberations in clinical practice. We explored if there is an alternative beyond the dichotomy of maintenance treatment and discontinuation of medications. Methods: We conducted a retrospective observational study by reviewing medical records at the study hospital of a cohort of patients since their participation in an early psychosis study starting from 2006, with special interests in patients able to maintain good functioning under treatment with a low antipsychotic dose. Results: Of the 81 patients with first-episode psychosis, 55 patients (67.9%) had follow-up information for longer than 5 years. The majority (n = 46, 83.6%) had non-affective psychosis, 20 patients (36.4%) had full-time employment/education by the time of their latest visit; among them, 15 patients received dosage of antipsychotics no more than the minimum effective dose [chlorpromazine equivalent (CPZE) dose, 200 mg/day]. Besides, 10 of 55 patients (18.2%) only received very low dose antipsychotics (CPZE < 50 mg/day) during maintenance, which was significantly correlated to good functioning. Being male, having a history of hospitalization, and being on clozapine therapy were correlated to poorer functioning. Antipsychotic-free status was achieved only in two non-psychotic patients. Conclusions: A substantial proportion of patients could achieve good functioning under low-dose antipsychotic maintenance after first-episode psychosis, even if they could not completely withdraw antipsychotics in the long term. Optimizing the balance between preventing relapse and preserving functioning by fine-tuning antipsychotic dosage during maintenance is a challenge warranting more clinical attention.

Continuous versus extended antipsychotic dosing in schizophrenia: Less is more

Antipsychotic drugs temper psychotic symptoms by interacting with dopamine D2 receptors to reduce dopamine neurotransmission. Currently, the standard of care involves antipsychotic treatment protocols that achieve steady-state levels of medication. Maintaining patients on continuous treatment is thought to be necessary to keep them stabilised. However, continuous antipsychotic exposure increases the risk of adverse effects over time. These effects include metabolic and cardiovascular disorders, extrapyramidal complications, and dopamine receptor supersensitivity, the latter of which could potentially promote both treatment tolerance and psychosis relapse. In the present review, we describe evidence showing that continuous exposure to antipsychotic drugs can not only worsen long-term outcome, but-past acute phase treatment-it is also unnecessary to effectively manage schizophrenia symptoms. We also describe evidence that regular but extended dosing, allowing predictable periods of lower antipsychotic levels/D2 occupancy, is both safe and effective in patients, and it greatly reduces drug exposure overall. Studies in laboratory animals show that compared to continuous antipsychotic exposure, regular but extended dosing actually has superior antipsychotic-like efficacy, and it also substantially reduces the likelihood of both motor side effects and dopamine receptor supersensitivity. We propose that regular, but extended dosing should be considered in the long-term treatment of people with schizophrenia, because the available evidence suggests it can be just as effective as continuous treatment, while decreasing overall drug exposure and potentially reducing harmful side effects.

Model-Guided Antipsychotic Dose Reduction in Schizophrenia: A Pilot, Single-Blind Randomized Controlled Trial

PURPOSE/BACKGROUND

Patients with schizophrenia as well as their psychiatrists are hesitant to reduce the antipsychotic dose in fear of relapse. To overcome such dilemmas, we developed models to individually calculate an oral dose that corresponds to a given target dopamine D2 receptor occupancy.

METHODS/PROCEDURES

In this pilot, 52-week single-blind randomized controlled trial, 35 clinically stable patients with schizophrenia receiving either risperidone or olanzapine monotherapy were randomly assigned to dose reduction (n = 17) or dose maintenance group (n = 18). In the former group, baseline doses were reduced to the doses corresponding to 65% D2 occupancy (the lower end of therapeutic window) at trough that were calculated from randomly collected plasma concentrations using our models.

FINDINGS/RESULTS

In the dose reduction group, doses of risperidone and olanzapine were decreased from 4.2 ± 1.9 to 1.4 ± 0.4 and 12.8 ± 3.9 to 6.7 ± 1.8 mg/d, whereas the doses in the dose maintenance group were 4.3 ± 1.9 and 15.8 ± 4.6 mg/d, respectively. Twelve subjects (70.5%) and 13 subjects (72.2%) in the dose reduction and dose maintenance groups completed the study (P = 0.604), whereas 3 subjects (18.8%) and none dropped out because of clinical worsening in the dose reduction and dose maintenance groups, respectively. There were not significant differences in score changes in Positive and Negative Syndrome Scale between the 2 groups but in Positive subscale scores in the Clinical Global Impression-Schizophrenia (0.4 ± 0.7 in the dose reduction group vs -0.1 ± 0.7 in the dose maintenance group, P = 0.029).

IMPLICATIONS/CONCLUSIONS

Although our model-guided dose reduction strategy was found to be comparable with no-dose change in terms of dropout rates, safety issues have to be further examined.

Achieving the Lowest Effective Antipsychotic Dose for Patients with Remitted Psychosis: A Proposed Guided Dose-Reduction Algorithm

Continuing antipsychotic treatment in patients with schizophrenia under clinical remission remains controversial. Even though the mainstream opinion declares an outweighed balance against medication discontinuation, recent reviews and critiques suggest that some patients may remain symptom free and well functioning after stopping antipsychotics, but few predictors can identify who can try medication discontinuation, whilst no guidelines exist for reducing medication to reach the lowest effective dose safely. Analyzing the findings from studies employing different methodologies, adopting evidence from pharmacodynamic research, and observing dose reduction in stable patients, as well as taking inspiration from the metaphor of the Cantor set in natural philosophy, we introduce an alternative solution and propose a guided dose-reduction algorithm that follows a set of clear precautions and instructions. The algorithm recommends only a fraction (no more than 25%) of the dosage to be reduced at a time, with at least a 6-month stabilization period required before reducing another 25% of the dose. Patients are empowered to actively participate in decision making when they are ready for further dose tapering, or should they retreat to a previous dosage if warning signs of a relapse re-emerge. An intermittent or irregular dosing schedule can be used to adapt this algorithm to real-world practice. Our preliminary findings suggest that patients with remitted psychosis can do well along this path. We anticipate that this approach can help optimize the risk-benefit ratio and instill a hope in patients with schizophrenia that they can maintain in stable remission under a lower antipsychotic dose without an increased risk of relapse.

Antipsychotic-Induced Dopamine Supersensitivity Psychosis: Pharmacology, Criteria, and Therapy

The first-line treatment for psychotic disorders remains antipsychotic drugs with receptor antagonist properties at D2-like dopamine receptors. However, long-term administration of antipsychotics can upregulate D2 receptors and produce receptor supersensitivity manifested by behavioral supersensitivity to dopamine stimulation in animals, and movement disorders and supersensitivity psychosis (SP) in patients. Antipsychotic-induced SP was first described as the emergence of psychotic symptoms with tardive dyskinesia (TD) and a fall in prolactin levels following drug discontinuation. In the era of first-generation antipsychotics, 4 clinical features characterized drug-induced SP: rapid relapse after drug discontinuation/dose reduction/switch of antipsychotics, tolerance to previously observed therapeutic effects, co-occurring TD, and psychotic exacerbation by life stressors. We review 3 recent studies on the prevalence rates of SP, and the link to treatment resistance and psychotic relapse in the era of second-generation antipsychotics (risperidone, paliperidone, perospirone, and long-acting injectable risperidone, olanzapine, quetiapine, and aripiprazole). These studies show that the prevalence rates of SP remain high in schizophrenia (30%) and higher (70%) in treatment-resistant schizophrenia. We then present neurobehavioral findings on antipsychotic-induced supersensitivity to dopamine from animal studies. Next, we propose criteria for SP, which describe psychotic symptoms and co-occurring movement disorders more precisely. Detection of mild/borderline drug-induced movement disorders permits early recognition of overblockade of D2 receptors, responsible for SP and TD. Finally, we describe 3 antipsychotic withdrawal syndromes, similar to those seen with other CNS drugs, and we propose approaches to treat, potentially prevent, or temporarily manage SP.

Plasma levels and estimated dopamine D2 receptor occupancy of long-acting injectable risperidone during maintenance treatment of schizophrenia: a 3-year follow-up study

INTRODUCTION

Dopamine D₂ receptor occupancy levels needed for the maintenance treatment of schizophrenia remain to be elucidated. We examined 3-year clinical outcomes of patients with schizophrenia who received long-acting injectable risperidone (LAI risperidone) at baseline and investigated their dopamine D₂ receptor occupancy levels, estimated from plasma drug concentrations.

METHODS

A chart review of 52 outpatients with schizophrenia who participated in the original cross-sectional study was conducted to examine their 3-year clinical outcomes between April and September 2015. Patients who continued outpatient treatment with LAI risperidone without any usage of concomitant chlorpromazine equivalent antipsychotic dosage at >200 mg/day for the 3-year period were asked to participate in the follow-up assessments that included the Brief Psychiatric Rating Scale (BPRS) and estimated dopamine D₂ receptor occupancy levels at trough, using plasma concentrations of risperidone plus 9-hydroxyrisperidone. Data were compared with the same patients collected 3 years earlier.

RESULTS

Among the original 52 participants, 14 participants (27 %) continued outpatient treatment with LAI risperidone. Ten participants (19 %) provided plasma samples; mean ± SD measured trough concentration of risperidone plus 9-hydroxyrisperidone significantly increased from 22.9 ± 15.6 to 31.8 ± 17.5 ng/mL (P = 0.02). Estimated dopamine D₂ receptor occupancy numerically increased from 63.0 ± 10.9 to 69.0 ± 11.0 % (P = 0.12). A significant worsening was observed in the BPRS total score among these patients (mean ± SD, 34.3 ± 12.7 to 46.5 ± 16.9, P = 0.003).

CONCLUSION

Paradoxically, the increased plasma concentration was found to be associated with a significant worsening of the clinical outcome. More investigations are indicated to shed further light on optimal levels of D₂ blockade in the maintenance treatment of schizophrenia.