The More, the Merrier…? Antipsychotic Polypharmacy Treatment Strategies in Schizophrenia From a Pharmacology Perspective

Efficacy and tolerability of antipsychotic polypharmacy for schizophrenia spectrum disorders. A systematic review and meta-analysis of individual patient data

BACKGROUND

Antipsychotic polypharmacy (APP) is frequently prescribed for schizophrenia-spectrum disorders. Despite the inconsistent findings on efficacy, APP may be beneficial for subgroups of psychotic patients. This meta-analysis of individual patient data investigated moderators of efficacy and tolerability of APP in adult patients with schizophrenia-spectrum disorders.

DESIGN

We searched PubMed, EMBASE, and the Cochrane Central Register of Randomized Trials until September 1, 2022, for randomized controlled trials comparing APP with antipsychotic monotherapy. We estimated the effects with a one-stage approach for patient-level moderators and a two-stage approach for study-level moderators, using (generalized) linear mixed-effects models. Primary outcome was treatment response, defined as a reduction of 25 % or more in the Positive and Negative Syndrome Scale (PANSS) score. Secondary outcomes were study discontinuation, and changes from baseline on the PANSS total score, its positive and negative symptom subscale scores, the Clinical Global Impressions Scale (CGI), and adverse effects.

RESULTS

We obtained individual patient data from 10 studies (602 patients; 31 % of all possible patients) and included 599 patients in our analysis. A higher baseline PANSS total score increased the chance of a response to APP (OR = 1.41, 95 % CI 1.02; 1.94, p = 0.037 per 10-point increase in baseline PANSS total), mainly driven by baseline positive symptoms. The same applied to changes on the PANSS positive symptom subscale and the CGI severity scale. Extrapyramidal side effects increased significantly where first and second-generation antipsychotics were co-prescribed. Study discontinuation was comparable between both treatment arms.

CONCLUSIONS

APP was effective in severely psychotic patients with high baseline PANSS total scores and predominantly positive symptoms. This effect must be weighed against potential adverse effects.

Cariprazine and clozapine combination for the treatment of psychosis in a young, female patient with schizophrenia: a case report

The task of a psychiatrist is to select the most appropriate medication or combination of drugs to treat the symptoms of schizophrenia while minimizing the risk of side effects and ensuring the patient achieves the highest level of functioning possible. This is a challenging task as the action of each drug or group of drugs is different. The efficacy of cariprazine, which affects D3 receptors as a D3/D2 receptor partial agonist, has been extensively studied and is one of the first medication choices by practicing psychiatrists when treating patients with negative symptomatology. In this clinical case, we demonstrate the effective and safe treatment of a patient's positive and affective symptoms using a combination of cariprazine, clozapine, and venlafaxine.

The management of patients with predominant negative symptoms in Slovakia: A 1-year longitudinal, prospective, multicentric cohort study

BACKGROUND

Predominant negative symptoms (PNSs) in schizophrenia can affect the patients' psychosocial functioning immensely and are less responsive to treatment than positive symptoms.

AIMS

The aim of the study was to observe negative symptoms and psychosocial functioning in PNS schizophrenia patients and to understand whether PNS can be improved and with what treatment strategies.

METHODS

This was a 1-year, prospective, multicentric cohort study conducted in Slovakia. Adult outpatients with diagnosis of schizophrenia according to ICD-10 and PNS evaluated using the criteria by the European Psychiatric Association's (EPA) guidance were included. Change in negative symptoms, functionality, and treatment patterns were observed. Treatment effectiveness was evaluated using the modified Short Assessment of Negative Domain (m-SAND), the Self-evaluation of Negative Symptoms (SNS) scale, the Personal and Social Performance (PSP) scale, and the Clinical Global Impression - Severity (CGI-S) and the Clinical Global Impression - Improvement (CGI-I) scales. Least-squares (LS) means were calculated for the change from baseline to final visit for the outcomes.

RESULTS

The study included 188 patients. Functionality improved as, by the end of the study, fewer patients were unemployed (53%) and more worked occasionally (21%). PNS improved significantly according to both physicians and patients (LS mean change from baseline in m-SAND total score: -10.0 (p-value <0.0001)). Most patients received polytherapy throughout the study. Cariprazine was utilized most (20% monotherapy and 76% polytherapy). Only a few patients discontinued treatment due to adverse drug reactions.

CONCLUSIONS

With the right treatment strategy, it is possible to achieve improvement in PNS and everyday functioning in schizophrenia outpatients.

Cariprazine augmentation of clozapine in schizophrenia-a retrospective chart review

The aim of our study was to evaluate the efficacy of cariprazine augmentation of clozapine in treatment-resistant schizophrenia in a retrospective chart review. Among 916 medical records of schizophrenia patients, we identified 12 individuals treated with a combination of those drugs for a duration of 3-60 weeks [median 32 (10-40)]. Clinical Global Impression-Improvement (CGI-I) scores were used to measure the treatment response between the introduction of cariprazine augmentation of clozapine and the last point of observation. The majority of the patients presented treatment response (9/12 patients, 75%) after 4-16 weeks of therapy [median 6 (4-12)]. Treatment was associated with the decrease in positive, negative, affective, and anxiety symptom severity, as well as improvement of patient global functioning. One patient discontinued the treatment due to side effects (akathisia), and two patients halted the therapy due to the exacerbation of psychotic symptoms. Our study presents a thorough clinical description of the largest number of treatment-resistant schizophrenia patients medicated using cariprazine augmentation of clozapine in a "real-world" setting. Our results suggest that the use of this combination may lead to the improvement in a broad range of symptoms of patients with this condition.

Dopamine partial agonists: a discrete class of antipsychotics

Worldwide, there are now three marketed dopamine D2 partial agonists: aripiprazole, brexpiprazole and cariprazine. These three drugs share a number of properties other than their action at D2 receptors. Pharmacologically, they are 5HT2 antagonists and D3 and 5HT1A partial agonists but with little or no alpha-adrenergic, anticholinergic or antihistaminic activity. They also share a long duration of action. Clinically, D2 partial agonists are effective antipsychotics and generally have useful antimanic and antidepressant activity. They are usually well tolerated, causing akathisia and insomnia only at the start of treatment, and are non-sedating. These drugs also share a very low risk of increased prolactin and of weight gain and accompanying metabolic effects. They may also have a relatively low risk of tardive dyskinesia. There is some evidence that they are preferred by patients to dopamine antagonists. Individual dopamineD2 partial agonists have much in common and as a group they differ importantly from dopamine D2 antagonists. Dopamine D2 partial agonists should be considered a distinct class of antipsychotics.Key pointsD2 partial agonists share many pharmacological and clinical propertiesD2 partial agonists differ in several important respects from D2 antagonistsD2 partial agonists should be considered a discrete class of antipsychotics.

A Survey Study on Clinicians' Rationale and Attitude Towards the Prescription of Antipsychotic Polypharmacy in the East Perth Metropolitan Area in Western Australia

Objective Patients challenging refractory and residual psychotic symptoms have led to the concomitant use of combined antipsychotics, which was later introduced and labelled 'antipsychotic polypharmacy' (APP). Many clinicians have become somewhat hesitant to adjust psychotropic medication dosages, resulting in a higher dose and combination prescription of antipsychotics and only achieving modest success. This study examines and investigates clinician perspectives and the rationale for the prescription of antipsychotic polypharmacy. Methods A structured questionnaire designed to reflect 15 target-directed questions evaluating clinicians' attitudes and rationale on antipsychotic polypharmacy prescription was administered from November to December 2022. Information was obtained from inpatient and outpatient prescribers (psychiatric consultants) in two government-funded psychiatric facilities and outpatient clinics in the East Perth Metropolitan Area in Western Australia. Results After exclusion, a total of 45 participants' responses were analysed. These results suggest a higher frequency of questions relating to the prescription of APP based on previous prescribers' consultation and recommendation from a prior treating team; senior nurses' pressure impacting clinicians' decisions on APP perception; and the patient's risk of aggression impacting the clinician's rationale for the prescription of APP. Conclusions Clinicians' rationale and attitude towards the prescription of APP are mostly influenced by recommendations from prior treatment teams or consultations and patients' risk for aggression without compromising practice guidelines. Our findings also highlight the need to evaluate prescribers' attitudes and how it presents an opportunity to enhance patients' holistic outcomes.

Safety of Antipsychotic Polypharmacy Versus Monotherapy in a Nationwide Cohort of 61,889 Patients With Schizophrenia

OBJECTIVES

The authors sought to study the safety of antipsychotic polypharmacy compared with monotherapy in specific dosage categories.

METHODS

Patients with schizophrenia (N=61,889; median follow-up, 14.8 years [IQR=7.4-22.0]) were identified from the Finnish nationwide inpatient care register and followed up over the period 1996-2017. Antipsychotic polypharmacy was compared with monotherapy in seven dosage categories (<0.4, 0.4-<0.6, 0.6-<0.9, 0.9-<1.1, 1.1-<1.4, 1.4-<1.6, and ≥1.6 defined daily doses [DDDs] per day) in terms of risk of severe physical morbidity, indicated by nonpsychiatric and cardiovascular hospitalizations (adjusted hazard ratio). Within-individual analysis was used in an effort to eliminate selection bias.

RESULTS

The mean age of the cohort was 46.7 years (SD=16.0), and 50.3% (N=31,104) were men. Among patients who had used both monotherapy and polypharmacy, the risk of nonpsychiatric hospitalization was significantly lower during polypharmacy use at all total dosage categories above 1.1 DDDs/day with differences up to -13% than during monotherapy use of the same dosage category (for 1.1-<1.4 DDDs/day, adjusted hazard ratio=0.91, 95% CI=0.87-0.95; for 1.4-<1.6 DDDs/day, adjusted hazard ratio=0.91, 95% CI=0.86-0.96; and for ≥1.6 DDDs/day, adjusted hazard ratio=0.87, 95% CI=0.84-0.89). The risk of cardiovascular hospitalization was significantly lower for polypharmacy at the highest total dosage category (-18%, adjusted hazard ratio=0.82, 95% CI=0.72-0.94). The results from the comparisons between monotherapy and no use and between polypharmacy and no use were in line with the primary comparison of polypharmacy and monotherapy within the same individual. Comparison of any polypharmacy use with any monotherapy use showed no significant difference for nonpsychiatric or cardiovascular hospitalization.

CONCLUSIONS

The results show that antipsychotic monotherapy is not associated with a lower risk of hospitalization for severe physical health problems when compared with antipsychotic polypharmacy. Treatment guidelines should not encourage use of monotherapy instead of antipsychotic polypharmacy without any existing evidence on the safety issues.

Antipsychotic prescribing practices for outpatients with schizophrenia and reasons for non-clozapine treatment - Data from a Danish quality assessment audit

BACKGROUND

Clozapine is the gold standard for treating treatment-resistant schizophrenia (TRS) although widely underutilised. Both organisational, patient- and clinician related reasons for the underutilisation have been reported, however, the clinical impact of either in real-world settings is not fully elucidated.

AIM

This audit aimed to evaluate the local antipsychotic (AP) prescribing practices for outpatients with schizophrenia and to assess the spectrum and prevalence of journalised reasons for non-clozapine treatment amongst eligible outpatients.

METHODS

Data on demographics, current and former AP treatments, as well as documented reasons for non-clozapine treatment, was extracted through chart audit.

RESULTS

Of the 668 affiliated outpatients with schizophrenia, 43% were treated with AP polytherapy (APP) and 19.6% with clozapine. The most prevalent reason for clozapine discontinuation was related to side effects whereas the most prevalent reason for refusal or omission of clozapine treatment was related to the associated monitoring regimen.

CONCLUSIONS

This audit showed that APP prescribing is a highly prevalent practice in our services when treating outpatients with schizophrenia and that clozapine is underutilised in a 'last resort' manner. The blood-monitoring regimen associated with clozapine treatment was found to be an important factor in the underutilisation. It seemed, however, that the monitoring constituted a barrier for different reasons, requiring different approaches to remedy. Future studies, directly involving both patients and clinicians in the identification and management of the most clinically relevant barriers and their corresponding facilitators, are warranted.

Successful switching from risperidone to cariprazine in a schizophrenic patient with pronounced functional deficit. Case report

A 22-year-old male was admitted to an in-patient psychiatric unit for treatment, after a period of 2 years of increasing psychotic symptoms corresponding to a very severe case of schizophrenia across the entire scale of symptom disorder domains along with some drug abuse comorbidity. Previous treatments with olanzapine (OLA) and risperidone (RIS) had been at best partly successful toward his positive symptoms with no, or even worsening effects on the negative symptomatology. Given the gravity of the latter symptoms and functional impairment of our patient, he might thus have been a candidate for clozapine (CLZ) treatment. It was however decided to switch his antipsychotic treatment to cariprazine (CAR), an agent with a novel pharmacological and clinical profile, because of its favorable pharmacodynamic, pharmacokinetic, and tolerability/safety properties. In a follow-up on the patient 6 months after discharge he is not fully recovered, but the recovery attained reflects a marked functional improvement compared to before the RIS-to-CAR switch. The remarkable response to CAR observed may, speculatively, be in line with the suggestion that CAR could offer an alternative, safer, and more tolerable monotherapy approach (vs. CLZ) for patients with severe negative symptoms and functional deficiency resistant to standard antipsychotic treatment. He appears to occasionally still be taking drugs, but no worsening of positive symptoms has been noted. Whether or not he could reach full recovery if he would abstain entirely from drugs of abuse remains an open question.

Case report: Successful administration of cariprazine in a young, severely ill patient with recurrent relapses of schizophrenia and persistent negative symptoms

The present case report describes a young man diagnosed with schizophrenia and presents a "revolving door" (RD) phenomenon. He was hospitalized in an acute psychiatric clinic three times in 1 year. After each hospitalization, he was discharged with incompletely reduced psychotic symptoms, persistent negative symptoms, low functioning, lack of insight, and adherence. He had an insufficient response to maximally tolerated doses of antipsychotic monotherapy with haloperidol and risperidone. Moreover, his treatment was complicated due to the low accessibility of long-acting injectable atypical antipsychotics (LAI) in the country and his refusal of the only available atypical LAI paliperidone palmitate and refusal to take clozapine. Due to limited alternatives, the decision to administer combinations of antipsychotics was made. Since his diagnosis, he received several combinations of antipsychotics, i.e., haloperidol + quetiapine, risperidone + quetiapine, haloperidol + olanzapine, risperidone + olanzapine, but without sufficient clinical effectiveness. Although combinations of antipsychotics reduced his positive symptoms to some degree, persistent negative symptoms and extrapyramidal side effects were observed. After initiating cariprazine, which was combined with olanzapine, improvement in the patient's positive symptoms, negative symptoms, and overall functioning was detected. The combination of medications mentioned above facilitated the therapeutic alliance, thus providing control over the symptoms and preventing psychiatric hospitalizations.

Remission of Persistent Negative Symptoms and Psychosocial Consequences by Combined Clozapine and Cariprazine Treatment in a Patient With Long-Standing Treatment-Resistant Schizoaffective Disorder

This patient case report describes a 45-year old white unmarried man with disability pension due to schizoaffective disorder, diagnosed at the age of 24. He lives in an apartment and has housing support. Retrospectively, the patient displayed prodromal markers of a disorder within the schizophrenia spectrum many years before the onset of frank psychosis, indeed since childhood. Over the years several symptoms and signs across schizophrenia domains have been manifest: positive, negative, cognitive, and affective, among which the negative and affective symptoms and signs were the earliest to appear. While the positive, disorganized, and catatonic symptoms responded to treatment - when duly tested and complied with - the negative and affective symptoms have been notoriously difficult to handle. We now report on the successful introduction of cariprazine (CAR) to his ongoing clozapine (CLZ) medication, the result of which has been a near-complete remission of his persistent negative and psychosocial issues. We interpret this remarkable alleviation of the patient's disease - and concomitant improvement of his quality of life - in terms of neuroreceptor target complementarity between CLZ and CAR, with particular emphasis on the contributions from the D3 and D2 receptor partial agonist components of the latter agent.