Potential treatment strategy of risperidone in long-acting injectable form for schizophrenia with dopamine supersensitivity psychosis

Efficacy of Asenapine in Drug-resistant Psychotic Patients with Dopamine Supersensitivity Psychosis: Two Cases

Dopamine supersensitivity psychosis (DSP) is an unstable clinical condition observed in individuals with schizophrenia who have been treated with an antipsychotic medication at a high dosage and/or for a long period. An up-regulation of dopamine D2 receptors (DRD2) is thought to be involved in the essential pathology of DSP. An antipsychotic agent with both tight binding to DRD2 and a long half-life is generally effective for treating DSP, but a patient who meets the criteria of treatment-resistant schizophrenia sometimes needs treatment with clozapine. We report the case details of two patients whose DSP was not controlled with several antipsychotics but was successfully controlled with asenapine. Asenapine binds to a broad range of dopamine receptors and serotonin receptors, and it is thus distinct from other atypical antipsychotics. The unique profile of asenapine may contribute to the control of severe DSP symptoms in individuals with schizophrenia.

A randomized-controlled trial of blonanserin and olanzapine as adjunct to antipsychotics in the treatment of patients with schizophrenia and dopamine supersensitivity psychosis: The ROADS study

Dopamine supersensitivity psychosis (DSP) is a key factor contributing to the development of antipsychotic treatment-resistant schizophrenia. We examined the efficacy and safety of blonanserin (BNS) and olanzapine (OLZ) as adjuncts to prior antipsychotic treatment in patients with schizophrenia and DSP in a 24-week, multicenter (17 sites), randomized, rater-blinded study with two parallel groups (BNS and OLZ add-on treatments) in patients with schizophrenia and DSP: the ROADS Study. The primary outcome was the change in the Positive and Negative Syndrome Scale (PANSS) total score from baseline to week 24. Secondary outcomes were changes in the PANSS subscale scores, Clinical Global Impressions, and Extrapyramidal Symptom Rating Scale (ESRS), and changes in antipsychotic doses. The 61 assessed patients were allocated into a BNS group (n = 26) and an OLZ group (n = 29). The PANSS total scores were reduced in both groups (mean ± SD: -14.8 ± 24.0, p = 0.0042; -10.5 ± 12.9, p = 0.0003; respectively) with no significant between-group difference (mean, -4.3, 95 %CI 15.1-6.4, p = 0.42). The BNS group showed significant reductions from week 4; the OLZ group showed significant reductions from week 8. The ESRS scores were reduced in the BNS group and the others were reduced in both groups. The antipsychotic monotherapy rates at the endpoint were 26.3 % (n = 6) for BNS and 23.8 % (n = 5) for OLZ. The concomitant antipsychotic doses were reduced in both groups with good tolerability. Our results suggest that augmentations with BNS and OLZ are antipsychotic treatment options for DSP patients, and BNS may be favorable for DSP based on the relatively quick responses to BNS observed herein.

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.

A critical appraisal of long acting injectable antipsychotics: Translating research to clinics

Long acting injections (LAI) are an effective alternative mode of administration of antipsychotics, less commonly used in clinical practice. Gap in knowledge base is an important source of attitudinal bias. Current article is focused on reviewing the literature for the principles underlying the choice, initiation, maintenance, switch and termination of an LAI; historical, pharmacological and clinical factors implicating the rationale of using LAI against oral agents and older against newer LAIs. Evidences available in clinical and basic psychopharmacological researches are critically appraised, highlighting the lacunae in our understanding. It is endeavored to open the window for the studies to be carried forward in the future answering critical questions which could lay a stronger base for clinical utility of different LAIs. Thus, this article tries to acquaint clinicians with the translatable knowledge imparted from the research and riposte queries for the researchers to explore in relation to LAI.

Effectiveness of blonanserin for patients with drug treatment-resistant schizophrenia and dopamine supersensitivity: A retrospective analysis

OBJECTIVE

Dopamine supersensitivity psychosis (DSP) is one of the key factors contributing to the development of antipsychotic treatment-resistant schizophrenia (TRS). We investigated the efficacy of blonanserin, an atypical antipsychotic, for patients with TRS and DSP.

METHODS

In this 12-month retrospective follow-up study, we investigated the cases of eight consecutive patients with unstable TRS and DSP treated with blonanserin as an add-on therapy. We examined changes in scores for the Brief Psychiatric Rating Scale (BPRS), Clinical Global Impression-Severity of Illness (CGI-S) scale and the Global Assessment of Functioning scale (GAF) during the 12 months after the administration of blonanserin.

RESULTS

The patients' total scores on the BPRS and GAF scores were significantly improved by 3 months at the latest. Positive BPRS and CGI-S scores were also improved by 6 months at the latest. The total chlorpromazine-equivalent doses of antipsychotics were significantly reduced from 1462.3±499.6mg to 794.1±642.8mg (p=0.001) after 12 months of blonanserin treatment, with a favorable safety and tolerability profile.

CONCLUSIONS

Blonanserin may be a promising antipsychotic for the treatment of TRS and DSP.

Risperidone long-acting injectable in the treatment of treatment-resistant schizophrenia with dopamine supersensitivity psychosis: Results of a 2-year prospective study, including an additional 1-year follow-up

Dopamine supersensitivity psychosis (DSP) resulting from antipsychotic treatment is related to treatment-resistant schizophrenia (TRS), and its treatment has not been established to date. Maintaining thoroughly stable occupancy of the dopamine D2 receptor by risperidone long-acting injectable (RLAI) is one strategy for treatment. In this study, RLAI was given as an adjunctive medication to oral antipsychotic(s), which were switched partially and gradually to RLAI in 108 treatment-resistant patients for an additional 1-year follow-up in a 2-year study, and to compare the effects in 72 patients with a DSP history (DSP group) and 36 patients without this history (NonDSP group). Although both groups showed significant improvements in the total Brief Psychotic Rating Scale (BPRS) score during the follow-up period, greater improvement was observed for the DSP group than the NonDSP group. High doses (> 850 mg chlorpromazine-dose combined of oral antipsychotics and RLAI) did not significantly change in both groups throughout the study period; however, extrapyramidal symptoms, including tardive dyskinesia, were significantly improved only in the patients with DSP. This study strongly suggested that the RLAI treatment, even with only partial switching, provides relief from refractory symptoms, particularly for patients with a history of DSP.

CLINICAL TRIAL REGISTRATION

http://www.umin.ac.jp/:UMIN000008487.

Dopamine supersensitivity psychosis as a pivotal factor in treatment-resistant schizophrenia

There may be subtypes in treatment-resistant schizophrenia (TRS), and one of the subtypes may be related to dopamine supersensitivity psychosis (DSP). In developing strategies for prevention and treatment TRS, it is important to clarify the role of DSP in TRS. TRS patients were recruited from 3 hospitals for the present study. Through chart reviews, all patients were judged as either TRS or not, and then possible TRS patients were investigated about their past/present histories of DSP episode(s) by direct interviews. We then compared each factor between the groups with and without DSP episode(s). Out of 611 patients screened, 147 patients met the criteria for TRS and were included in the present analysis. These were divided into groups with and without DSP, comprising 106 (72.1%) and 41 patients (27.9%), respectively. Clinical characteristics in the two groups were similar, except for drug-induced movement disorders (DIMDs), which were significantly more important in DSP patients. Of the DSP patients, 42% and 56% experienced rebound psychosis and tolerance to antipsychotic effects, respectively. The present study revealed that approximately 70% of TRS patients experienced one or more DSP episodes, which may have a strong impact on the long-term prognosis of patients with schizophrenia.

A prospective comparative study of risperidone long-acting injectable for treatment-resistant schizophrenia with dopamine supersensitivity psychosis

OBJECTIVE

Dopamine supersensitivity psychosis (DSP) is considered to be one cause of treatment-resistant schizophrenia (TRS). The authors investigated the efficacy of risperidone long-acting injections (RLAI) in patients with TRS and DSP.

METHOD

This is a multicenter, prospective, 12-month follow-up, observational study that included unstable and severe TRS patients with and without DSP. 115 patients with TRS were recruited and divided into two groups according to the presence or absence of DSP which was judged on the basis of the clinical courses and neurological examinations. RLAI was administered adjunctively once every 2weeks along with oral antipsychotics. We observed changes in scores for the Brief Psychiatric Rating Scales (BPRS), Clinical Global Impression-Severity of Illness (CGI-S), Global Assessment of Functioning Scale (GAF), and Extrapyramidal Symptom Rating Scale (ESRS) during the study. Of the assessed 94 patients, 61 and 33 were categorized into the DSP and NonDSP groups, respectively.

RESULTS

While baseline BPRS total scores, CGI-S scores and GAF scores did not differ, the ESRS score was significantly higher in the DSP group compared with the NonDSP group. Treatment significantly reduced BPRS total scores and CGI-S scores, and increased GAF scores in both groups, but the magnitudes of change were significantly greater in the DSP group relative to the NonDSP group. ESRS scores were also reduced in the DSP group. Responder rates (≥20% reduction in BPRS total score) were 62.3% in the DSP group and 21.2% in the NonDSP group.

CONCLUSIONS

It is suggested that DSP contributes to the etiology of TRS. Atypical antipsychotic drugs in long-acting forms, such as RLAI, can provide beneficial effects for patients with DSP.

CLINICAL TRIALS REGISTRATION

UMIN (UMIN000008487).

Is schizophrenia a dopamine supersensitivity psychotic reaction?

Adolf Meyer (1866-1950) did not see schizophrenia as a discrete disorder with a specific etiology but, rather, as a reaction to a wide variety of biopsychosocial factors. He may have been right. Today, we have evidence that gene mutations, brain injury, drug use (cocaine, amphetamine, marijuana, phencyclidine, and steroids), prenatal infection and malnutrition, social isolation and marginalization, can all result in the signs and symptoms of schizophrenia. This clinical picture is generally associated with supersensitivity to dopamine, and activates dopamine neurotransmission that is usually alleviated or blocked by drugs that block dopamine D2 receptors. While the dopamine neural pathway may be a final common route to many of the clinical symptoms, the components of this pathway, such as dopamine release and number of D2 receptors, are approximately normal in schizophrenia patients who are in remission. Postmortem findings, however, reveal more dimers of D1D2 and D2D2 receptors in both human schizophrenia brains and in animal models of schizophrenia. Another finding in animal models is an elevation of high-affinity state D2High receptors, but no radioactive ligand is yet available to selectively label D2High receptors in humans. It is suggested that synaptic dopamine supersensitivity in schizophrenia is an attempt at compensation for the original damage by heightening dopamine neurotransmission pathways (preparing the organism for fight or flight). The dopamine overactivity is experienced subjectively as overstimulation, which accounts for some of the clinical symptoms, with attempts at dampening down the stimulation leading to still other symptoms. Reaction and counter-reaction may explain the symptoms of schizophrenia.

Optimal extent of dopamine D2 receptor occupancy by antipsychotics for treatment of dopamine supersensitivity psychosis and late-onset psychosis

Several studies have proposed an optimal dopamine D2 receptor occupancy by antipsychotics (OOc) to establish optimal pharmacological treatment of schizophrenia. However, there are limitations to the use of the OOc, especially in application to patients with treatment-resistant schizophrenia, including dopamine supersensitivity psychosis (DSP) or late-onset psychosis (LOP). It has been suggested that D2 receptor density is up-regulated by chronic treatment of antipsychotics in DSP, whereas it may be low in LOP owing to age-related reduction. In estimation of the proposed OOc, these alterations have not been taken into account, which may be one of the factors contributing to the limited application of this index. We here hypothesize that there is an optimal range in the number of D2 receptors available for dopamine binding to elicit adequate neurotransmission in the treatment of patients with schizophrenia. We then estimated the OOc under the assumption that the range is constant while D2 density is variable. The results showed that the OOc and plasma level of antipsychotics increase with an increase in the D2 density but decrease with a decrease in the D2 density. That is, if the range of OOc is 65% to 78% in a standard D2 density, it becomes 82% to 89% under 2-fold up-regulated density and 42% to 63% under a 40% reduced density. The results also indicated that the reduction of the plasma antipsychotic level is greater during a given time period in patients with higher D2 density, as they need a higher antipsychotic dose to achieve the raised OOc, which would account for the clinical features of DSP, for example, acute exacerbation after a discontinuation of antipsychotics. On the other hand, in patients with lower D2 density, only a lower antipsychotic dose will achieve the OOc, and a small increase in the dose will result in a greater increase in occupancy and induce extrapyramidal adverse effects more easily. Furthermore, the reduction of the plasma antipsychotic level during the time period is smaller, which prolongs extrapyramidal adverse effects after discontinuation of antipsychotics in LOP. We also attempted to develop a strategy for the prevention and treatment of patients with DSP or LOP by focusing on D2 density.