Advancements in Non-Dopaminergic Treatments for Schizophrenia: A Systematic Review of Pipeline Developments.

INTRODUCTION: Conventional antipsychotic drugs that attenuate dopaminergic neural transmission are ineffective in approximately one-third of patients with schizophrenia. This necessitates the development of non-dopaminergic agents. METHODS: A systematic search was conducted for completed phase II and III trials of compounds for schizophrenia treatment using the US Clinical Trials Registry and the EU Clinical Trials Register. Compounds demonstrating significant superiority over placebo in the primary outcome measure in the latest phase II and III trials were identified. Collateral information on the included compounds was gathered through manual searches in PubMed and press releases. RESULTS: Sixteen compounds were identified; four compounds (ulotaront, xanomeline/trospium chloride, vabicaserin, and roluperidone) were investigated as monotherapy and the remaining 12 (pimavanserin, bitopertin, BI 425809, encenicline, tropisetron, pregnenolone, D-serine, estradiol, tolcapone, valacyclovir, cannabidiol, and rimonabant) were examined as add-on therapy. Compared to the placebo, ulotaront, xanomeline/trospium chloride, vabicaserin, bitopertin, estradiol, cannabidiol, rimonabant, and D-serine showed efficacy for positive symptoms; roluperidone and pimavanserin were effective for negative symptoms; and encenicline, tropisetron, pregnenolone, tolcapone, BI 425809, and valacyclovir improved cognitive function. DISCUSSION: Compounds that function differently from existing antipsychotics may offer novel symptom-specific therapeutic strategies for patients with schizophrenia.

Comparable Psychotropic Prescription Rates After Hospital Discharge Between Patients with COVID-19 and Those With Non-COVID-19-Related Respiratory Infection.

INTRODUCTION: Whether psychiatric symptoms after recovery from coronavirus disease 2019 (COVID-19) are specific to this illness remains unclear. METHODS: In this retrospective study, the Diagnosis Procedure Combination data and outpatient clinic data were used for patients who received inpatient treatment in Saiseikai-affiliated hospitals for COVID-19 or other respiratory tract infections (non-COVID) from 2020 to 2022. The primary outcome was new prescriptions of psychotropic drugs after discharge (i. e., prescriptions of psychotropics to patients who had not received them before or during their hospitalization). Values of interest were compared between groups using the chi-square test or Fisher's exact test. A COX proportional-hazards model was used to examine factors associated with psychotropic prescriptions after discharge in age- and sex-matched COVID-19 and non-COVID patients. RESULTS: Of 31,993 chart records, 19,613 were excluded due to a positive history with psychiatric disorders (n=2,445), prescriptions of psychotropics (n=744), and no follow-ups (n=16,424). Thus, 3,648 COVID-19 and 8,732 non-COVID patients were included (mean [range] duration of follow-up, days: 146.9 [1-727] and 239.2 [1-729], respectively). Two hundred and four (5.6%) of the 3,648 patients with COVID-19 received psychotropic prescriptions after discharge. No statistically significant differences were observed in the prescription rates of any psychotropic category between the COVID-19 and non-COVID groups. An increase in severity during hospitalization was significantly associated with more frequent psychotropic prescriptions (hazard ratio 1.83, p<0.001). DISCUSSION: The development of psychiatric symptoms should be closely observed, especially in patients who experienced increased severity during hospitalization, regardless of whether they suffered from COVID-19.

Factor Analysis of Patients Who Find Tablets or Capsules Difficult to Swallow Due to Their Large Size: Using the Personal Health Record Infrastructure of Electronic Medication Notebooks.

BACKGROUND: Understanding patient preference regarding taking tablet or capsule formulations plays a pivotal role in treatment efficacy and adherence. Therefore, these preferences should be taken into account when designing formulations and prescriptions. OBJECTIVE: This study investigates the factors affecting patient preference in patients who have difficulties swallowing large tablets or capsules and aims to identify appropriate sizes for tablets and capsules. METHODS: A robust data set was developed based on a questionnaire survey conducted from December 1, 2022, to December 7, 2022, using the harmo smartphone app operated by harmo Co, Ltd. The data set included patient input regarding their tablet and capsule preferences, personal health records (including dispensing history), and drug formulation information (available from package inserts). Based on the medication formulation information, 6 indices were set for each of the tablets or capsules that were considered difficult to swallow owing to their large size and concomitant tablets or capsules (used as controls). Receiver operating characteristic (ROC) analysis was used to evaluate the performance of each index. The index demonstrating the highest area under the curve of the ROC was selected as the best index to determine the tablet or capsule size that leads to swallowing difficulties. From the generated ROCs, the point with the highest discriminative performance that maximized the Youden index was identified, and the optimal threshold for each index was calculated. Multivariate logistic regression analysis was performed to identify the risk factors contributing to difficulty in swallowing oversized tablets or capsules. Additionally, decision tree analysis was performed to estimate the combined risk from several factors, using risk factors that were significant in the multivariate logistic regression analysis. RESULTS: This study analyzed 147 large tablets or capsules and 624 control tablets or capsules. The "long diameter + short diameter + thickness" index (with a 21.5 mm threshold) was identified as the best indicator for causing swallowing difficulties in patients. The multivariate logistic regression analysis (including 132 patients with swallowing difficulties and 1283 patients without) results identified the following contributory risk factors: aged <50 years (odds ratio [OR] 1.59, 95% CI 1.03-2.44), female (OR 2.54, 95% CI 1.70-3.78), dysphagia (OR 3.54, 95% CI 2.22-5.65), and taking large tablets or capsules (OR 9.74, 95% CI 5.19-18.29). The decision tree analysis results suggested an elevated risk of swallowing difficulties for patients with taking large tablets or capsules. CONCLUSIONS: This study identified the most appropriate index and threshold for indicating that a given tablet or capsule size will cause swallowing difficulties, as well as the contributory risk factors. Although some sampling biases (eg, only including smartphone users) may exist, our results can guide the design of patient-friendly formulations and prescriptions, promoting better medication adherence.

Adverse Event Signal Detection Using Patients' Concerns in Pharmaceutical Care Records: Evaluation of Deep Learning Models.

BACKGROUND: Early detection of adverse events and their management are crucial to improving anticancer treatment outcomes, and listening to patients' subjective opinions (patients' voices) can make a major contribution to improving safety management. Recent progress in deep learning technologies has enabled various new approaches for the evaluation of safety-related events based on patient-generated text data, but few studies have focused on the improvement of real-time safety monitoring for individual patients. In addition, no study has yet been performed to validate deep learning models for screening patients' narratives for clinically important adverse event signals that require medical intervention. In our previous work, novel deep learning models have been developed to detect adverse event signals for hand-foot syndrome or adverse events limiting patients' daily lives from the authored narratives of patients with cancer, aiming ultimately to use them as safety monitoring support tools for individual patients. OBJECTIVE: This study was designed to evaluate whether our deep learning models can screen clinically important adverse event signals that require intervention by health care professionals. The applicability of our deep learning models to data on patients' concerns at pharmacies was also assessed. METHODS: Pharmaceutical care records at community pharmacies were used for the evaluation of our deep learning models. The records followed the SOAP format, consisting of subjective (S), objective (O), assessment (A), and plan (P) columns. Because of the unique combination of patients' concerns in the S column and the professional records of the pharmacists, this was considered a suitable data for the present purpose. Our deep learning models were applied to the S records of patients with cancer, and the extracted adverse event signals were assessed in relation to medical actions and prescribed drugs. RESULTS: From 30,784 S records of 2479 patients with at least 1 prescription of anticancer drugs, our deep learning models extracted true adverse event signals with more than 80% accuracy for both hand-foot syndrome (n=152, 91%) and adverse events limiting patients' daily lives (n=157, 80.1%). The deep learning models were also able to screen adverse event signals that require medical intervention by health care providers. The extracted adverse event signals could reflect the side effects of anticancer drugs used by the patients based on analysis of prescribed anticancer drugs. "Pain or numbness" (n=57, 36.3%), "fever" (n=46, 29.3%), and "nausea" (n=40, 25.5%) were common symptoms out of the true adverse event signals identified by the model for adverse events limiting patients' daily lives. CONCLUSIONS: Our deep learning models were able to screen clinically important adverse event signals that require intervention for symptoms. It was also confirmed that these deep learning models could be applied to patients' subjective information recorded in pharmaceutical care records accumulated during pharmacists' daily work.

Real-world evidence of fremanezumab for treating migraine in Japan: a retrospective study.

BACKGROUND: There have been very few real-world studies reported in the literature solely focusing on fremanezumab in Asia. This study aimed to evaluate the efficacy and safety of fremanezumab in a real-world setting in Japan. METHOD: This single-centered, observational, retrospective study examined patients with migraines who received four doses of fremanezumab between December 2021 and August 2022 at Keio University Hospital. We assessed the changes in monthly migraine days, responder rates, and migraine-associated symptoms, as well as injection site reactions and adverse events. RESULT: Twenty-nine patients were enrolled, wherein 79.3% were women. Compared with those at baseline, the monthly migraine days decreased by 5.9 days at 4 months. The 50% responder rate was 55.2% at 4 months. A total of 57.9%, 47.8%, and 65.0% of patients showed improvement in the severity of photophobia, phonophobia, and nausea/vomiting, respectively. Moreover, injection site reactions were the most common adverse events (55.2%). CONCLUSION: Fremanezumab is effective and safe for migraine prevention in Japan. Fremanezumab also improved migraine-associated symptoms in half of the patients.

Influence of Voiced and Semi-voiced Sounds on the Subjective Similarity of Different Drug Names: A Cognitive Psychological Experiment.

The similarity of drug names is one of the common causes of medication error. In Japan, similarity evaluation is performed prior to approval of new drugs in order to avoid potential confusion. However, existing indices do not take account of the difference between characters that contain voiced or semi-voiced and unvoiced sounds, so it is not clear whether such sounds influence the subjective similarity of drug names. Thus, we performed a cognitive psychological experiment to investigate this issue, using participants who had not received any education in medicine, nursing, or pharmacy. An analogue scale questionnaire was used to evaluate the subjective similarity of the names of drug pairs. Drug pairs for the main analysis were prepared by matching the first 0 to 3 characters, and then varying the difference in the number of voiced and semi-voiced characters from 0 to 3 in these matched characters. By means of this procedure, the drug pairs were classified into a total of 10 groups. Then, a total of 60 drug pairs were created by assigning 6 drugs to each group. The subjective similarity tended to increase with increasing number of common characters among the first three characters. When classified according to the number of these common characters, the subjective similarity was significantly decreased when voiced or semi-voiced sounds were present, as compared with when they were absent. These results indicate that a new drug name similarity index that takes account of voiced and semi-voiced sound differences should be developed to minimize medication errors.

Investigation of Prescription Status and Exploration of Risk Factors Related to Denosumab-Induced Hypocalcemia in Combination Therapy with 1α,25-Dihydroxy-vitamin D3.

To prevent denosumab-induced hypocalcemia in patients with renal dysfunction, combination therapy with 1α,25-dihydroxy-vitamin D3 (active vitamin D) is recommended. We previously developed a risk prediction model for hypocalcemia in patients with cholecalciferol/calcium (natural vitamin D). However, the prescription status and the risk factors of patients with active vitamin D have not been identified, so we designed this retrospective observational study using a large practice database covering June 2013 to May 2020 to analyze prescription status and risk factors. Patients were classified according to vitamin D type. After that, factors associated with development of hypocalcemia in patients with active vitamin D were explored. Univariate analysis was conducted to compare patient backgrounds between the hypocalcemia and non-hypocalcemia groups. Receiver operating characteristic analysis was conducted to evaluate the predictive potential of the extracted factors. Of the 33442 patients who received denosumab, 22347 and 3560 patients were co-administered natural and active vitamin D, respectively. Patients with active vitamin D had significantly lower renal function (estimated glomerular filtration rate (eGFR) median: 74.0 vs. 69.7 mL/min/1.73 m2), but some patients (23.6%) with sufficient renal function (eGFR ≥90) were also receiving active vitamin D. Of the 3560 patients with active vitamin D, non-hypocalcemia (n = 166) and hypocalcemia (n = 17) groups who met the study criteria were analyzed. Renal function was lower in the hypocalcemia group, and alkaline phosphatase gave the best discrimination. High aspartate aminotransferase (AST), renal dysfunction, high alkaline phosphatase (ALP), and low hemoglobin may be significant factors in risk prediction for hypocalcemia in patients with active vitamin D.

Transferability Based on Drug Structure Similarity in the Automatic Classification of Noncompliant Drug Use on Social Media: Natural Language Processing Approach.

BACKGROUND: Medication noncompliance is a critical issue because of the increased number of drugs sold on the web. Web-based drug distribution is difficult to control, causing problems such as drug noncompliance and abuse. The existing medication compliance surveys lack completeness because it is impossible to cover patients who do not go to the hospital or provide accurate information to their doctors, so a social media-based approach is being explored to collect information about drug use. Social media data, which includes information on drug usage by users, can be used to detect drug abuse and medication compliance in patients. OBJECTIVE: This study aimed to assess how the structural similarity of drugs affects the efficiency of machine learning models for text classification of drug noncompliance. METHODS: This study analyzed 22,022 tweets about 20 different drugs. The tweets were labeled as either noncompliant use or mention, noncompliant sales, general use, or general mention. The study compares 2 methods for training machine learning models for text classification: single-sub-corpus transfer learning, in which a model is trained on tweets about a single drug and then tested on tweets about other drugs, and multi-sub-corpus incremental learning, in which models are trained on tweets about drugs in order of their structural similarity. The performance of a machine learning model trained on a single subcorpus (a data set of tweets about a specific category of drugs) was compared to the performance of a model trained on multiple subcorpora (data sets of tweets about multiple categories of drugs). RESULTS: The results showed that the performance of the model trained on a single subcorpus varied depending on the specific drug used for training. The Tanimoto similarity (a measure of the structural similarity between compounds) was weakly correlated with the classification results. The model trained by transfer learning a corpus of drugs with close structural similarity performed better than the model trained by randomly adding a subcorpus when the number of subcorpora was small. CONCLUSIONS: The results suggest that structural similarity improves the classification performance of messages about unknown drugs if the drugs in the training corpus are few. On the other hand, this indicates that there is little need to consider the influence of the Tanimoto structural similarity if a sufficient variety of drugs are ensured.

Predicting response to CGRP-monoclonal antibodies in patients with migraine in Japan: a single-centre retrospective observational study.

BACKGROUND: Anti-calcitonin gene-related peptide monoclonal antibodies (CGRPmAbs) are a favourable option for patients with migraine who experience distressful headache disability and fail to respond to traditional preventive treatment options. However, since CGRPmAb has been available for only 2 years in Japan, the difference between good and poor responders remains unknown. We aimed to investigate the clinical characteristics of patients with migraine in Japan who responded well to CGRPmAb based on real-world data. METHODS: We analysed patients who visited Keio University Hospital, Tokyo, Japan, between the 12th of August 2021 and 31st of August 2022, and were prescribed one of three CGRPmAbs (erenumab, galcanezumab, and fremanezumab) for more than 3 months. We recorded the patients' basic migraine characteristics, such as pain quality, monthly migraine days (MMD)/monthly headache days (MHD), and the number of prior treatment failures. We defined good responders as patients whose MMDs decreased by more than 50% after 3 months of treatment and other patients as poor responders. We compared the baseline migraine characteristics between the two groups and performed logistic regression analysis based on the items that showed statistically significant differences. RESULTS: In total, 101 patients were considered eligible for the responder analysis (galcanezumab: 57 (56%), fremanezumab: 31 (31%), and erenumab: 13 (13%)). After 3 months of treatment, 55 (54%) patients achieved ≥ 50% reduction in MMDs. Comparisons between ≥ 50% responders and non-responders revealed that age was significantly higher (p = 0.003), and MHD and total prior treatment failures were significantly lower (p = 0.027, 0.040, respectively), in responders than in non-responders. Age was a positive predictive factor, and the total number of prior treatment failures and past medical history of immuno-rheumatologic diseases were negative predictive factors of CGRPmAb responsiveness in Japanese patients with migraine. CONCLUSIONS: Patients with migraine who are older, with fewer prior treatment failures and no past history of immuno-rheumatologic disease, may respond well to CGRPmAbs.

Real-world evidence of galcanezumab for migraine treatment in Japan: a retrospective analysis.

OBJECTIVE: To evaluate the efficacy and safety of galcanezumab in patients with migraine in a real-world setting in Japan. BACKGROUND: Galcanezumab is the first anti-calcitonin gene-related peptide monoclonal antibody approved in Japan. To the best of our knowledge, no real-world studies on galcanezumab have been published in any international journal from Japan. METHODS: We retrospectively examined patients with migraine who received three doses of galcanezumab between August 2021 and February 2022 at the Keio University Hospital. We assessed changes in monthly migraine days, responder rate, and migraine-associated and premonitory symptoms. We also investigated injection site reactions and adverse events. RESULTS: Fifty-two patients received three doses of galcanezumab during the study period. Compared with those at baseline, the monthly migraine days decreased by 5.9 days (95% confidence interval, 4.2-7.7) at 3 months. The 50% responder rate was 61.5% at 3 months. A total of 64.9%, 50.0%, and 63.9% of patients showed improvement in the severity of photophobia, phonophobia, and nausea/vomiting, respectively. Premonitory symptoms without subsequent headache were reported in 62.5% of patients. Moreover, injection site reaction was the most common adverse event (34.6%). CONCLUSION: This study revealed the efficacy and safety of galcanezumab for migraineurs in Japan. Galcanezumab also improved migraine-associated symptoms. However, despite a reduction in headaches, premonitory symptoms without subsequent headache were reported in > 50% of the patients at 3 months.

Latent class analysis of patients' background factors affecting the risk of specific adverse drug reactions to dipeptidyl peptidase 4 inhibitors.

BACKGROUND AND PURPOSE: Spontaneous reporting is widely used to identify adverse drug reactions (ADRs), but relatively little is known about the relationships between specific ADRs and background factors of affected patients. Here, we applied latent class analysis (LCA) to identify background factors associated with different ADRs in type 2 diabetes patients treated with dipeptidyl peptidase 4 (DPP-4) inhibitors, using the Japanese Adverse Drug Event Report (JADER) database. MATERIALS AND METHODS: Patients using only a DPP-4 inhibitor who encountered ADRs were selected from the JADER database up to April 2019 (N = 3,577). LCA was employed to classify these cases based on underlying diseases and lifestyle factors (alcohol, tobacco, diet, and exercise) and to identify characteristic ADRs in each class. The optimum number of classes was determined by selecting the model with the lowest value of the Bayesian information criterion (BIC). RESULTS: A six-class model had the lowest BIC, and these classes were characterized by specific background factors and ADRs. For example, one class included diabetes complications, while another class included exercise and diet as background factors. Increased risk of a specific ADR(s), such as pancreatitis or pemphigoid, was found in each class. The nine DPP-4 inhibitors were not uniformly distributed among the classes, though individual classes included patients receiving different inhibitors. CONCLUSION: Our findings indicate that characteristic background factors of patients experiencing specific DPP-4 inhibitor-induced ADRs reported in the JADER database are different and can be classified by LCA. This methodology may be useful for predicting ADRs not detected during drug development.

Analysis of contributory factors to incidents related to medication assistance for residents taking medicines in residential care homes for the elderly: a qualitative interview survey with care home staff.

BACKGROUND: In Japan, staff who are not doctors or nurses can assist the elderly in residential care facilities to take their pre-packaged medicines. Therefore, there is a potential risk of incidents specific to staffs. The aim of this study was to clarify the causes of incidents related to medication assistance by staff in residential care facilities. METHOD: Semi-structured interviews with staff involved in medication incidents in long-term care facilities, focusing on how and why each incident happened, were conducted. The interview covered basic information about the subject and resident, the circumstances under which the incident had occurred, contributing factors, and countermeasures put in place. Verbatim transcripts of the interviews were prepared. Based on thematic analysis, codes and themes were created. RESULTS: Twelve subjects participated in this study. All subjects were staffs (not doctors or nurses) in long-term care facilities. All incidents covered in this study were incidents in which the wrong resident was given the medication. The incidents arose because of "not following procedures", such as lack of "self-check of residents' faces/residents' names/residents' medicine envelopes" or "double-check with other staff" or "using a device for medication intake". Contributory factors were grouped into four categories: individual resident factor items such as "decreased ability to understand their medication" or "refusal to take medicines", individual staff factor items such as "lack of knowledge related to medication" or "mental burden" or "experience in medication assistance", team factor items such as "failure to communicate with other staff", work environment factor items such as "presence of other residents" or "other work besides medication assistance" or "not enough time" or "little understanding of fostering a safety culture at the facility". CONCLUSION: This study identified four categories of contributory factors that may lead to incidents during medication assistance by caregivers for residents of care homes. These findings should be helpful for risk management in residential care facilities where staff usually provide medication assistance. Separation of meal times and medication assistance, and professional review to stagger the timing of administration of residents' medication may be effective in reducing incidents.

Information provision and retrieval by registered salespersons from consumers during over-the-counter drug sales - a questionnaire survey.

BACKGROUND: In Japan, non-pharmacists who are accredited as registered salespersons can sell over-the-counter (OTC) drugs, and they play a very important role in supporting proper OTC drug use by consumers. The purpose of this study was to evaluate information provided to and information collected from consumers, and cooperation with pharmacists during OTC drug sales by registered salespersons, and to clarify their related concerns and behaviors. METHODS: A cross-sectional questionnaire-based survey of 385 registered salespersons working at 56 drugstores throughout Japan was conducted. Based on the questionnaire survey, the frequency of information provision/collection in various categories was determined for the registered salespersons. The relation between concerns of registered salespersons relating to OTC drug sales and the frequency of information provision/collection was examined. The frequency of consultation of registered salespersons with a pharmacist was calculated for registered salespersons with/without in-store pharmacists. The χ-square test or Fisher's exact test was performed to assess the significance of differences. RESULTS: Two hundred and seven registered salespersons (53.7%) responded completely. A greater number of OTC drug purchasers per day was associated with a greater frequency of information provision about "side effects" and information collection about "favorite items" (alcohol, tobacco, health foods, etc.) (p < 0.05). One hundred and thirty-nine (67.2%) participants had concerns about "interactions between OTC drugs and prescription drugs", and these concerns were related to the frequency of information provision/collection (p < 0.05). Regarding the frequency of consultation with a pharmacist, 35 of 46 participants (76.1%) working with pharmacists answered "always" or "usually", whereas only 19 of 161 participants (11.8%) working without full-time pharmacists answered "always" or "usually". More than half of the registered salespersons thought that cooperation with a pharmacist was necessary when they were "asked about concomitant use with prescription drugs" or "told that side effects happened." CONCLUSIONS: The results of this study show that experienced registered salespersons selling OTC drugs are more likely to collect information from consumers and to provide information to consumers. It appears to be important for registered salespersons to cooperate with pharmacists in order to provide and collect appropriate information about concomitant medications.

Questionnaire survey investigation of the present status of dietetic consultation at community pharmacies from the perspectives of registered dietitians and pharmacists.

BACKGROUND: Registered dietitians are rarely employed at community pharmacies in Japan, even though dietetic advice might benefit some patients. OBJECTIVE: To clarify the present status of dietetic consultation provided by registered dietitians and their collaboration with pharmacists in community pharmacies. METHODS: We conducted a cross-sectional questionnaire-based survey of pharmacists and registered dietitians who work in community pharmacies. The surveyed items were: frequency of dietetic consultation, awareness of one's knowledge and ability to conduct dietetic consultation, concerns, pharmacists' recognition of the need for nutritional support at community pharmacies, and cooperation between registered dietitians and pharmacists. RESULTS: Sixty-six registered dietitians, 53 pharmacists in pharmacies with registered dietitians/dietitians, and 110 pharmacists in pharmacies without registered dietitians/dietitians responded. The frequency of dietetic consultation regarding obesity and hypertension was significantly higher for registered dietitians than for pharmacists. The ability to conduct dietetic consultation regarding diseases/conditions such as kidney disease not requiring dialysis, hyperuricemia, gout, obesity and hypertension was also significantly higher for dietitians than pharmacists. More than 70% of pharmacists recognized the importance of nutritional support at community pharmacies, while 56.1% of registered dietitians noted that they were not able to fully utilize their occupational abilities. Registered dietitians were divided into two groups: registered dietitians who answered that they were able to utilize their occupational abilities and those that answered they were not. The former group was more likely to ask pharmacists about patients' medication for dietetic consultation and to be asked to provide dietetic consultation to patients. The latter group was more likely to find difficulty in scheduling dietetic consultation. CONCLUSION: Our results suggest that registered dietitians in community pharmacies have a greater explanatory ability than pharmacists concerning nutritional and dietary management for patients. It may be important for pharmacists to improve cooperation with registered dietitians by providing more opportunities for dietetic consultation.

Prediction of sustained fetal toxicity induced by ketoprofen based on PK/PD analysis using human placental perfusion and rat toxicity data.

AIM: We encountered a case of fetal toxicity due to ductus arteriosus (DA) constriction in a 36-week pregnant woman who had applied multiple ketoprofen patches. The aim of the present study was to present the case and develop a model to predict quantitatively the fetal toxicity risk of transdermal administration of ketoprofen. METHODS: Human placenta perfusion studies were conducted to estimate transplacental pharmacokinetic (PK) parameters. Using a developed model and these parameters, human fetal plasma concentration profiles of ketoprofen administered to mothers were simulated. Using pregnant rats, DA constriction and fetal plasma drug concentration after ketoprofen administration were measured, fitted to an Emax model, and extrapolated to humans. RESULTS: Transplacental transfer value at the steady state of ketoprofen was 4.82%, which was approximately half that of antipyrine (passive marker). The model and PK parameters predicted almost equivalent mother and fetus drug concentrations at steady state after transdermal ketoprofen administration in humans. Maximum DA constriction and maximum plasma concentration of ketoprofen after administration to rat dams were observed at different times: 4 h and 1 h, respectively. The model accurately described the delay in DA constriction with respect to the fetal ketoprofen concentration profile. The model with effect compartment and the obtained parameters predicted that use of multiple ketoprofen patches could potentially cause severe DA constriction in the human fetus, and that fetal toxicity might persist after ketoprofen discontinuation by the mother, as observed in our case. CONCLUSION: The present approach successfully described the sustained fetal toxicity after discontinuing the transdermal administration of ketoprofen.

Analysis of the Mechanism of Prolonged Persistence of Drug Interaction between Terbinafine and Amitriptyline or Nortriptyline.

The purpose of the study was to quantitatively estimate and predict drug interactions between terbinafine and tricyclic antidepressants (TCAs), amitriptyline or nortriptyline, based on in vitro studies. Inhibition of TCA-metabolizing activity by terbinafine was investigated using human liver microsomes. Based on the unbound Ki values obtained in vitro and reported pharmacokinetic parameters, a pharmacokinetic model of drug interaction was fitted to the reported plasma concentration profiles of TCAs administered concomitantly with terbinafine to obtain the drug-drug interaction parameters. Then, the model was used to predict nortriptyline plasma concentration with concomitant administration of terbinafine and changes of area under the curve (AUC) of nortriptyline after cessation of terbinafine. The CYP2D6 inhibitory potency of terbinafine was unaffected by preincubation, so the inhibition seems to be reversible. Terbinafine competitively inhibited amitriptyline or nortriptyline E-10-hydroxylation, with unbound Ki values of 13.7 and 12.4 nM, respectively. Observed plasma concentrations of TCAs administered concomitantly with terbinafine were successfully simulated with the drug interaction model using the in vitro parameters. Model-predicted nortriptyline plasma concentration after concomitant nortriptylene/terbinafine administration for two weeks exceeded the toxic level, and drug interaction was predicted to be prolonged; the AUC of nortriptyline was predicted to be increased by 2.5- or 2.0- and 1.5-fold at 0, 3 and 6 months after cessation of terbinafine, respectively. The developed model enables us to quantitatively predict the prolonged drug interaction between terbinafine and TCAs. The model should be helpful for clinical management of terbinafine-CYP2D6 substrate drug interactions, which are difficult to predict due to their time-dependency.

Induced next-day somnolence in an elderly patient taking suvorexant concomitantly with diltiazem.

OBJECTIVE: To present the first case of induced next-day somnolence in a patient taking suvorexant concomitantly with diltiazem. CASE SUMMARY: The patient was an 88-year-old female who had suffered from insomnia and anorexia, for which a psychiatric clinic had prescribed 1.5 mg/day aripiprazole and 15 mg/day suvorexant (both once daily at bedtime), which cured her insomnia. Subsequently, a different hospital prescribed diltiazem hydrochloride (100 mg, sustained-release, daily after breakfast) for treatment of hypertension. After starting diltiazem, the patient was unable to wake up in the morning and overslept by ~ 3 hours. On the third day of taking diltiazem, the patient, on the basis of her own judgment, took only half a tablet of suvorexant, and found that she was able to sleep, and there was no somnolence the following morning. As halving suvorexant tablets is an off-label usage, and lower-dose tablets are not available, her prescription was switched to 1-mg rilmazafone hydrochloride. Since then, her sleep disorder has not recurred. DISCUSSION: Because suvorexant is metabolized by CYP3A4, next-day somnolence could have occurred as a result of increased plasma suvorexant concentration due to CYP3A4 inhibition by diltiazem. CONCLUSION: Elderly patients may suffer next-day somnolence if they concomitantly take suvorexant and sustained-release diltiazem hydrochloride, even if the diltiazem dose is low and there is a significant interval between the administration times of the two drugs. In order to avoid drug interaction, it may be desirable to switch from suvorexant to a different soporific that is not metabolized by CYP3A4.

Prediction of fetal ductus arteriosus constriction by systemic and local dermatological formulations of NSAIDs based on PK/PD analysis.

AIM: Use of nonsteroidal antiinflammatory drugs (NSAIDs) during the final trimester of pregnancy can cause fetal toxicity, such as ductus arteriosus (DA) constriction. The aim of this study was to predict quantitatively the fetal DA-constrictive effects of NSAIDs after various routes of administration to the mother by means of harmacokinetic/pharmacodynamic (PK/PD) modeling. METHODS: We evaluated acetaminophen, which is a first-line analgesic/antipyretic for the third trimester of pregnancy, together with the following NSAIDs: indometacin, diclofenac, ibuprofen, flurbiprofen, ketoprofen, loxoprofen, felbinac, naproxen, and celecoxib. Drug concentration data obtained in rats and humans were collected from the literature to calculate PK parameters. Next, the PD parameters for DA constriction in rats were obtained by fitting an Emax model to the DA/pulmonary artery (PA) inner diameter ratio after oral administration of each drug to full-term pregnant rats (data taken from the literature) and the unbound plasma concentration in rat dams estimated from the obtained PK parameters. Finally, the inner DA diameter profile after administration of each drug to human mothers was predicted. RESULTS: This PK/PD model predicted continuous fetal DA constriction in third-trimester women after repeated systemic use of nearly all the NSAIDs evaluated. Local dermatological formulations of NSAIDs were also predicted to potentially cause DA constriction. CONCLUSION: These results suggest that risk to the fetus should be carefully considered before administration of NSAIDs (especially systemic formulations, but including dermatological formulations) to women in the third trimester of pregnancy.

Sisters who developed piloerection after administration of milnacipran.

OBJECTIVE: We previously reported the first case of piloerection in a patient receiving milnacipran hydrochloride (MLP). Here, we now present a second case of MLP-induced piloerection. We discuss this effect in terms of α1-adrenoceptor occupancy. CASE SUMMARY: After the first case of MLP-induced piloerection, we monitored occurrence of piloerection in our patients taking MLP. In response to our interview, a 43-year-old woman who had been prescribed MLP by a psychiatrist for depression mentioned that piloerection occurred frequently all over her body, starting soon after initiation of MLP administration (50 mg/day). Although she was concerned at the time, she assumed it might be related to her depression or to coldness in winter. She also mentioned that the incidence of piloerection increased with MLP dose escalation. The piloerection disappeared after several months. Interestingly, the previous patient and the current patient are biological sisters. DISCUSSION: Changes in α1-adrenoceptor occupancy by endogenous norepinephrine (as an index of the risk of piloerection) in the presence of MLP were estimated. The occupancy values increased with MLP dose escalation, in accordance with the patient's report of the phenomenon. other concomitant drugs, such as nortriptyline, had little effect. Since the two patients were sisters, genetic factors might influence the risk of piloerection. CONCLUSION: The incidence of piloerection appeared to increase with MLP dose escalation in this patient, who was the biological sister of the previously reported patient. Clinicians should recognize the possibility of MLP-induced piloerection in view of its potential impact on patients' quality of life and on drug compliance.

Pharmacokinetic model analysis of interaction between phenytoin and capecitabine.

OBJECTIVE: Recent reports have shbown an increase in serum phenytoin levels resulting in phenytoin toxicity after initiation of luoropyrimidine chemotherapy. To prevent phenytoin intoxication, phenytoin dosage must be adjusted. We sought to develop a pharmacokinetic model of the interaction between phenytoin and capecitabine. METHODS: We developed the phenytoin-capecitabine interaction model on the assumption that fluorouracil (5-FU) inhibits cytochrome P450 (CYP) 2C9 synthesis in a concentration- dependent manner. The plasma 5-FU concentration after oral administration of capecitabine was estimated using a conventional compartment model. Nonlinear pharmacokinetics of phenytoin was modeled by incorporating the Michaelis-Menten equation to represent the saturation of phenytoin metabolism. The resulting model was fitted to data from our previously-reported cases. RESULTS: The developed phenytoincapecitabine interaction model successfully described the profiles of serum phenytoin concentration in patients who received phenytoin and capecitabine concomitantly. The 50% inhibitory 5-FU concentration for CYP2C9 synthesis and the degradation rate constant of CYP2C9 were estimated to be 0.00310 ng/mL and 0.0768 day-1, respectively. This model and these parameters allow us to predict the appropriate phenytoin dosage schedule when capecitabine is administered concomitantly. CONCLUSIONS: This newly-developed model accurately describes changes in phenytoin concentration during concomitant capecitabine chemotherapy, and it may be clinically useful for predicting appropriate phenytoin dosage adjustments for maintaining serum phenytoin levels within the therapeutic range.