Subjective assessment of brexpiprazole in patients with schizophrenia: a prospective observational study

OBJECTIVES

To investigate the subjective assessments of an antipsychotic treatment with brexpiprazole.

METHODS

This was a 14-week prospective observational study. Nineteen patients participated in the study between February 2019 and January 2020.

RESULTS

Patients had a mean age of 40.6±14.2 years and a Clinical Global Impressions-Severity of Illness scale (CGI-S) score of 4.6±1.2 at the initiation of brexpiprazole treatment. The Subjective Well-being under Neuroleptic drug treatment Short form, Japanese version (SWNS-J) total score significantly improved from 68.1±22.3 in week 2 to 79.5±21.0 in week 14 (p=0.0084). The SWNS-J subscales of self-control and social integration status also significantly improved from 14.0±4.7 and 13.9±6.0 in week 2 to 17.0±4.7 and 16.0±5.1 in week 14, respectively (p=0.0053 and 0.012, respectively). No significant improvements were observed in any other SWNS-J subscales or the Drug Attitude Inventory-10 (DAI-10) in the 14-week observation period. Moreover, the SWNS-J total score did not correlate with the DAI-10 (r=0.31, p=0.19), or CGI-S (r=-0.18, p=0.47) scores.

CONCLUSIONS

The present results suggest that brexpiprazole might improve subjective well-being, although this may not necessarily reflect psychopathological improvements. To enhance medication adherence, it is important to perform subjective assessments on patients over time.

Analysis of clozapine-induced seizures using the Japanese Adverse Drug Event Report database

Among antipsychotics, clozapine is associated with a high risk of seizures. This study aimed to generate novel hypotheses regarding trends in the onset of clozapine-induced seizures using the JADER (Japanese Adverse Drug Event Report) database. Seizures were defined according to the Standardized MedDRA Queries (SMQ) for convulsions (SMQ20000079). Trends in the onset of clozapine-induced seizures were assessed using multivariate logistic regression analysis with covariates of sex, age, clozapine dose, antipsychotic polypharmacy, concomitant medications, and history of convulsive disorder. In addition, we assessed the time-to-onset of clozapine-induced seizures using the median time, interquartile range, and Weibull shape parameter. The JADER database registered 2,745 cases of adverse events with clozapine, and 1,784 cases were included in the analysis after excluding cases for which clinical information was not available. Medium (200-400 mg) and high (> 400 mg) doses of clozapine had a significantly higher reporting rate of seizures than low doses (< 200 mg) (adjusted reporting odds ratio [aROR] = 3.05, 95% confidence interval [CI]: 1.86-4.99 and aROR = 9.81, 95% CI: 6.06-15.89, respectively). Younger age, antipsychotic polypharmacy, and concomitant use of lithium were also significantly associated with reports of seizures. The time-to-onset analysis of 222 cases of clozapine-induced seizures showed that the median time was 134 (interquartile range, 72-295) days. The 95% CI of the WSP β-value for clozapine-induced seizures included 1 and was classified as a random failure type. In conclusion, the results suggest that clozapine-induced seizures are dose-dependent adverse events that should be monitored with consideration of the effects of age and concomitant medications. Further epidemiological research is needed to strengthen and validate our hypotheses.

Analysis of signal components < 500 Hz in brain organoids coupled to microelectrode arrays: A reliable test-bed for preclinical seizure liability assessment of drugs and screening of antiepileptic drugs

Brain organoids with three-dimensional structure and tissue-like function are highly demanded for brain disease research and drug evaluation. However, to our knowledge, methods for measuring and analyzing brain organoid function have not been developed yet. This study focused on the frequency components of an obtained waveform below 500 Hz using planner microelectrode array (MEA) and evaluated the response to the convulsants pentylenetetrazol (PTZ) and strychnine as well as the antiepileptic drugs (AEDs) perampanel and phenytoin. Sudden and persistent seizure-like firing was observed with PTZ administration, displaying a concentration-dependent periodic activity with the frequency component enhanced even in one oscillation characteristic. On the other hand, in the administration of AEDs, the frequency of oscillation decreased in a concentration-dependent manner and the intensity of the frequency component in one oscillation also decreased. Interestingly, at low doses of phenytoin, a group of synchronized bursts was formed, which was different from the response to the perampanel. Frequency components contained information on cerebral organoid function, and MEA was proven useful in predicting the seizure liability of drugs and evaluating the effect of AEDs with a different mechanism of action. In addition, frequency component analysis of brain organoids using MEA is an important analysis method to perform in vitro to in vivo extrapolation in the future, which will help explore the function of the organoid itself, study human brain developments, and treat various brain diseases.

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Frequency analysis <500 Hz was performed in brain organoids coupled to planner microelectrode arrays (MEA).

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Concentration-dependent changes in frequency components were detected in responses to convulsants and antiepileptic drugs (AEDs).

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Analysis of signal components <500 Hz in brain organoids is a useful method for preclinical seizure liability assessment of drugs and screening of antiepileptic drugs.

Toxicological evaluation of convulsant and anticonvulsant drugs in human induced pluripotent stem cell-derived cortical neuronal networks using an MEA system

Functional evaluation assays using human induced pluripotent stem cell (hiPSC)-derived neurons can predict the convulsion toxicity of new drugs and the neurological effects of antiepileptic drugs. However, differences in responsiveness depending on convulsant type and antiepileptic drugs, and an evaluation index capable of comparing in vitro responses with in vivo responses are not well known. We observed the difference in synchronized burst patterns in the epileptiform activities induced by pentylentetrazole (PTZ) and 4-aminopryridine (4-AP) with different action mechanisms using multi-electrode arrays (MEAs); we also observed that 100 µM of the antiepileptic drug phenytoin suppressed epileptiform activities induced by PTZ, but increased those induced by 4-AP. To compare in vitro results with in vivo convulsive responses, frequency analysis of below 250 Hz, excluding the spike component, was performed. The in vivo convulsive firing enhancement of the high γ wave and β wave component were observed remarkably in in vitro hiPSC-derived neurons with astrocytes in co-culture. MEA measurement of hiPSC-derived neurons in co-culture with astrocytes and our analysis methods, including frequency analysis, appear effective for predicting convulsion toxicity, side effects, and their mechanism of action as well as the comparison of convulsions induced in vivo.

Detection of synchronized burst firing in cultured human induced pluripotent stem cell-derived neurons using a 4-step method

Human induced pluripotent stem cell-derived neurons are promising for use in toxicity evaluations in nonclinical studies. The multi-electrode array (MEA) assay is used in such evaluation systems because it can measure the electrophysiological function of a neural network noninvasively and with high throughput. Synchronized burst firing (SBF) is the main analytic parameter of pharmacological effects in MEA data, but an accurate method for detecting SBFs has not been established. In this study, we present a 4-step method that accurately detects a target SBF confirmed by the researcher's interpretation of a raster plot. This method calculates one set parameter per step, in the following order: the inter-spike interval (ISI), the number of spikes in an SBF, the inter-SBF interval, and the number of spikes in an SBF again. We found that the 4-step method is advantageous over the conventional method because it determines the preferable duration of an SBF, accurately distinguishes continuous SBFs, detects weak SBFs, and avoids false detection of SBFs. We found also that pharmacological evaluations involving SBF analysis may differ depending on whether the 4-step or conventional threshold method is used. This 4-step method may contribute to improving the accuracy of drug toxicity and efficacy evaluations using human induced pluripotent stem cell-derived neurons.

Effects of operating conditions on selectivity of a plasma fractionator in double filtration plasmapheresis

In a typical double filtration plasmapheresis treatment, plasma fractionation between albumin and some immunoglobulins associated with toxins is limited because none of the currently available plasma fractionators has a strict cutoff property for these proteins. Selectivity of immunoglobulins over albumin depends not only on the cutoff properties of the membrane but on the operating conditions such as the flow rate of the supplied plasma (Q(P)) and retained plasma to be discarded (Q(D)) in the plasma fractionator. We carried out an in vitro study using human plasma harvested by single plasma exchange treatments to assess the selectivity of a plasma fractionator, Evaflux 2A-F (Kawasumi Laboratories, Inc., Tokyo, Japan), under various operating conditions. The results of rate-constant filtration experiments showed that the concentrations in the feed tank and the sieving coefficient (SC) values of every protein were decreased slightly within 2 h after the start of the experiment because of membrane trapping, adsorption, and/or plugging. The time-averaged SC value of albumin increased with flow rate ratio (Q(P)/Q(D)) due to increasing filtration fraction (FF), but relative removal efficiency (mD/mP*) for albumin decreased with Q(P)/ Q(D) due to decreasing Q(D). For immunoglobulins, on the other hand, the SC values were almost unchanged, and the mD/mP* values increased with Q(P)/Q(D) due to an increase in FF. Both increasing Q(P) and decreasing Q(D) are effective means of improving selectivity between these proteins in the plasma fractionator. Membrane fouling is, however, obvious beyond a Q(P)/Q(D) value that is thought to be a critical point. Operation should be conducted below the critical Q(P)/Q(D) value, which depends on the patient's plasma components and the cutoff property of the membrane.

Collaborative work to evaluate toxicity on male reproductive organs by repeated dose studies in rats 15). Two-week and 4-week administration study of methyl methanesulfonate (MMS)

This study was conducted to assess whether a 2-week treatment period is as effective as 4-week treatment for detection of drug-induced toxicity on the male rat reproductive organs using methyl methanesulfonate (MMS). A two-week study at dose levels of 20 or 40 mg/kg and a 4-week study with 20 mg/kg were conducted. The results can be summarized as follows. No deaths and no apparent clinical signs were observed. Body weights and food consumption were decreased at 40 mg/kg in the 2-week study along with testis and epididymis weights. In the 4-week study, epididymis weights were decreased at 20 mg/kg. The rats treated with 20 mg/kg in the 4-week study and those treated with 40 mg/kg in the 2-week study showed decrease of germ cells, exfoliation of germ cells, vacuolar degeneration of Sertoli cell and cell debris in epididymal ducts on histopathological observation. MMS impairment of spermatogenesis was confirmed by stage analysis. It was concluded that a treatment period of 2 weeks is sufficient to allow evaluation of toxic effects of MMS on the male reproductive organs.

Continuous monitoring of blood volume in double filtration plasmapheresis

A continuous hematocrit (HCT) monitor, Crit-Line, was introduced to examine the change in patients' blood volume (BV) due to albumin loss during double filtration plasmapheresis (DFPP) treatments. Nine patients with autoimmune diseases or ABO incompatible renal transplantation received 15 DFPP treatments under Crit-Line monitoring. In these patients, plasma albumin concentration (C(P)) changed from 3.7 +/- 0.6 g/dl to 3.5 +/- 0.5 g/dl and HCT from 28.7% +/- 3.3% to 31.3% +/- 4.3% (change ratio [CR] of BV = -8.1%) during treatment with albumin concentrations (C(S)) of 9.5 +/- 1.0 g/dl and 500 ml volumes (V(S)) of supplementation fluid. Although the apparent CR value of C(P) was -5.3%, on average, the CR of albumin in the patients' plasma (M(P)) was -16.1%, which means a corrected CR value of C(P) by the HCT value to eliminate the influence of the patient's blood volume contraction during treatment. Albumin loss usually occurred in DFPP treatments. The decrease in BV was induced by an oncotic pressure drop due to albumin loss, and often resulted in a blood pressure drop. The amount of albumin loss during DFPP treatments strongly depends on sieving coefficients of the plasma separator (SC(PS)) and the plasma fractionator (SC(PF)), the filtration fraction of the plasma fractionator (FF(PF)), pretreatment C(P) value, and C(S) and V(S) values of the supplementation fluid. To determine the optimum C(S) and V(S) values for each patient, the authors introduced a variable blood volume model for albumin transport in DFPP. In this model, changes in C(P), HCT, and BV values could be estimated during treatment. For example, a patient with an HCT of 31.2%, body weight of 61.1 kg, and pretreatment C(P) of 4.4 g/dl received a DFPP treatment using a plasma separator, OP-05 (SC(PS) of 0.99), and a plasma fractionator, Evaflux 2A (SC(PF) of 0.40), under FF(PF) of 0.8 with a V(S) of 500 ml. A value for C(S) of about 10 g/dl is required for the patient to maintain a normal C(P) level during treatment by an estimation from the model. As a result of the treatment with a C(S) of 10 g/dl, the patient had no adverse reactions, such as a blood pressure decrease, during treatment under these conditions.

Transfer of male or female primordial germ cells of quail into chick embryonic gonads

Blood from an individual quail embryo at stages 13-16, when primordial germ cells (PGCs) were in circulation, was taken from its marginal vein and transfused into the marginal vein of a chick embryo at stages 13-16. Both donor and recipient embryos were cultured in vitro until day 8 of development and their sex was determined by morphological and histological observations of the gonads. Sections of recipient gonads were stained immunohistochemically with QCR1 monoclonal antibody positive for quail PGCs but negative for chick PGCs. Donor and recipient embryos were sexed in 17 pairs which included all four sex combinations. Transferred PGCs, either female-derived ZW type or male-derived ZZ type, were observed in the gonads of both sexes of 15 recipient embryos. The population of donor PGCs ranged from 20 to over 2500. In all four sex combinations, there was a higher population in the left than the right gonad of the embryos.

Development of murine monoclonal antibodies against an enterotoxin produced by Bacillus cereus

Three murine monoclonal antibodies (MAbs) were prepared against an enterotoxin (ET) produced by Bacillus cereus. Although these MAbs were found to react with the ET, their specificities appeared to be different in competitive binding assays. One of the MAbs (D-8), which was highly reactive with the ET, will be useful in developing immunological methods to detect crude ET and to isolate the ET in high yield.

Basic studies on visible light-curing resin for denture base. Part 8. The hardening depth of denture relining material after penetration of light through the denture base resin

A study was performed to examine how the duration of irradiation at the time of relining with visible light-curing material influences the depth of hardening of the relining material, in relation to the thickness of the denture base placed between the denture and the relining material. It was found that for a range of denture base thickness of 1-2.5 mm, a desirable degree of hardening could be obtained using an irradiation time of 20 s for relining material with a thickness of up to 4 mm used for the basal surface.