Differences in drug pharmacokinetics between East Asians and Caucasians and the role of genetic polymorphisms

Pharmacokinetic properties of once-weekly insulin icodec in Chinese individuals with type 2 diabetes

INTRODUCTION

Insulin icodec is a novel once-weekly basal insulin developed for the treatment of diabetes. The aim of this study was to investigate the pharmacokinetics of icodec in Chinese individuals with type 2 diabetes.

MATERIALS AND METHODS

In an open-label, single-group study, 24 Chinese individuals with type 2 diabetes (18-64 years, glycated hemoglobin ≤9.0%, body mass index 18.0-38.0 kg/m2) were treated with once-weekly icodec for 6 weeks. The icodec dose was constant and individualized, aimed at achieving self-measured plasma glucose of 4.4-7.0 mmol/L before breakfast. Blood samples were drawn from the first icodec dose until 35 days after last dose and were analyzed for total serum icodec concentration (i.e., the sum of albumin-bound and unbound icodec).

RESULTS

Icodec trough concentrations measured following initiation of once-weekly icodec dosing suggested that clinical steady state for icodec was achieved after approximately 3-4 weeks of dosing. When at steady state, icodec exposure covered the full 1-week dosing interval. The geometric mean half-life was 159 h. The slopes of total icodec exposure (AUCτ,SS) and maximum icodec concentration (Cmax,SS) vs icodec dose did not differ significantly from 1, supporting dose-proportionality for both AUCτ,SS (P = 0.40) and Cmax,SS (P = 0.43). Icodec was safe and well tolerated, and no new safety issues were identified in relation to icodec in this study.

DISCUSSION

The pharmacokinetic properties of icodec assessed at steady state in this study demonstrated well-distributed exposure across the 1-week dosing interval and a half-life that supports once-weekly administration in Chinese individuals with type 2 diabetes.

Effects of statin use on blood pressure and other hypertension-related outcome indicators in hypertensive patients: A systematic review and meta-analysis

AIMS

This meta-analysis delved into the impact of statin therapy, both as a monotherapy and in conjunction with antihypertensive medications, on blood pressure levels and outcomes pertinent to hypertension.

METHODS

We searched the PubMed, EMBASE, and Cochrane databases for studies published before October 1 2023. Studies designed as cohort studies or randomized controlled trials and investigating the effects of single use of statin or its combined use with other antihypertensive therapy were included. Authors extracted the data independently and differences were decided through discussion. Random-effects model was used to evaluate the merged outcomes. Due to the high heterogeneity of the HDL-C group, we performed subgroup analysis according to the type of statin. To assess the robustness and potential publication bias of our findings, we utilized sensitivity analysis, Egger's test, and funnel plots.

RESULTS

23 trials were included in this meta-analysis. The primary outcomes revealed that administering statins did not significantly impact the systolic pressure (SBP) of hypertensive patients (MD, -1.77; 95 % CI, -4.82-1.27). -The promoted effect of statin treatment on diastolic pressure (DBP) in hypertensive patients was found (MD, -1.87; 95 % CI, -3.72 --0.01). The secondary outcomes revealed that the use of statins resulted in a significant reduction in low-density lipoprotein (LDL-C), while significantly increasing high-density lipoprotein (HDL-C) in hypertensive patients.

CONCLUSION

Statin use did not modulate SBP and DBP of patients with hypertension, but SBP was decreased in the rosuvastatin or pravastatin subgroup, while DBP was decreased in the simvastatin or pravastatin subgroup. Statin treatment reduced LDL-C, increased HDL-C, and reduced the incidence of cardiovascular events and mortality compared to control groups.

Exploration of pharmacokinetic differences between East Asians and Caucasians: insights from pharmacokinetic studies in healthy subjects

Interethnic differences in the pharmacokinetics of drugs result from a complex interplay of environmental, genetic, and demographic factors. Identifying ethnic differences in pharmacokinetics is challenging due to the multifaceted contributions of the underlying factors. To address these challenges, this paper reviews 9 pharmacokinetic studies meeting the following criteria: (A) Conducted at Seoul National University Hospital from 2013 to 2022 as a single-center study. (B) Pharmacokinetic studies involving both East Asians (Korean, Japanese, or Chinese) and Caucasians. (C) Study drugs were administered orally. (D) Raw data was provided for reanalysis. This retrospective analysis aimed to investigate the existence of ethnic differences in drug exposure and understand the possible factors contributing to these variabilities. Pharmacokinetic, demographic, and clinical laboratory test data were analyzed to assess potential pharmacokinetic differences between East Asians and Caucasians. This assessment involved calculating the geometric mean ratio of dose-normalized area under the time-concentration curve (AUC) and dose- and weight-normalized AUC, along with their 90% confidence intervals. Additionally, pharmacological information, including metabolic pathways, was gathered from the investigational brochure or the respective country's drug label. Among 9 studies, 4 studies demonstrated approximately 1.3 to 1.8 times higher drug exposure in East Asians compared to Caucasians. These drugs were primarily eliminated through hepatic metabolism, with less than 5% excreted unchanged in the urine. Two drugs were metabolized by hepatic cytochrome P450 3A4, one by glutathione S-transferase, and specific metabolic pathways for another drug were not identified. Further research is needed to assess the causes of ethnic variability in these drugs.

Impact of CYP2D6 and ADRB1 polymorphisms on heart rate of post-PCI patients treated with metoprolol

Aim: To explore the effect of CYP2D6*10 (100C > T) and ADRB1 1165 G > C polymorphisms on heart rate of post-PCI (percutaneous coronary intervention) patients treated with metoprolol succinate sustained-release tablets. Methods: A total of 756 inpatients with metoprolol succinate sustained-release tablets were selected and the genotypes of CYP2D6*10 and ADRB1 1165G > C were detected in 319 patients using gene chip detection. The target heart rate was defined as a resting heart rate < 70 beats/min. Clinical data were collected. Results: A total of 319 inpatients were enrolled in the study. The mutant allele frequencies of CYP2D6 and ADRB1 were 57.21 and 69.44%, respectively. Whatever the dose of metoprolol, the heart rates were lower in patients with homozygous mutation of CYP2D6 than those with heterozygous mutation and wild-type (p < 0.05). Nevertheless, this effect was not seen between different genotypes of ADRB1. Logistic regression analysis showed that the dose of metoprolol and the genotypes of CYP2D6 were predictors of heart rate <70 beats/min in these patients. Further multivariate analysis indicated that patients with homozygous mutation had better control of heart rates compared with those with wild-type and heterozygous mutation of CYP2D6*10 genotypes (all: p < 0.001). Conclusion:CYP2D6*10 polymorphisms were associated with the heart rate of post-PCI patients treated with metoprolol succinate sustained-release tablets.

Safety, Tolerability, and Pharmacokinetics of Oral BI 1358894 in Healthy Japanese Male Volunteers

BACKGROUND AND OBJECTIVES: BI 1358894, a novel small-molecule inhibitor of transient receptor potential canonical ion channels, is under development for treatment of major depressive disorder. Phase I trials assessing the safety and pharmacokinetics of BI 1358894 in Caucasian male healthy volunteers (HVs) have been performed. This Phase I, double-blind, placebo-controlled, parallel-group trial assessed the safety, tolerability and pharmacokinetics of BI 1358894 in Japanese male HVs.

METHODS

Male HVs were randomized to receive oral BI 1358894 (n = 18) or placebo (n = 6) after a high-fat, high-calorie meal within three dose groups (50 mg, 100 mg, 200 mg), administered sequentially in dose-ascending order. The primary endpoint was number of HVs with drug-related adverse events (DRAEs). Secondary endpoints were the pharmacokinetic parameters of BI 1358894.

RESULTS

Overall, 24 male HVs entered the trial [mean (standard deviation) age: 30.0 (7.6) years]. DRAEs occurred in 3/18 HVs (BI 1358894 100 mg group: one HV experienced dizziness and headache; BI 1358894 200 mg group: one HV experienced headache, another reported sleep disorder). BI 1358894 exposure increased dose dependently and proportionally, peaking 4-6 h after administration before declining in a multiphasic manner with a terminal elimination half-life of ~70 h in the 50 mg and 100 mg dose groups, and 203 h in the 200 mg dose group.

CONCLUSION

BI 1358894 was well tolerated with a favorable pharmacokinetic profile in Japanese male HVs, similar to findings from a previous study in Caucasian male HVs.

TRIAL REGISTRATION

ClinicalTrials.gov (NCT03875001; 08-Mar-2019).

Chinese Expert Consensus on the Clinical Diagnosis and Management of Statin Intolerance

The clinical benefits of statins have well-established and recognized worldwide. Although statins are well-tolerated generally, however, the report of statin-related adverse event and statin intolerance are common in China, which results in insufficient use of statins and poor adherence. The main reason may be attributed to confusions or misconceptions in the clinical diagnosis and management in China, including the lack of unified definitions and diagnostic standards, broad grasp of diagnosis, and unscientific management strategies. Based on that, this consensus carefully summarized the statin-related gene polymorphism and statin usage issue among Chinese population, and comprehensively reviewed global research data on statin intolerance, referenced guidelines, and consensus literature on statin intolerance in foreign and different regions, proposes an appropriate and easy to implement statin intolerance definition as well as corresponding diagnostic criteria and management strategies for Chinese clinicians, in order to improve the clinical application of statin drugs and enhance the prevention and treatment level of atherosclerotic cardiovascular disease in China.

Critical insights into the evolving drug-approval process in China

Efforts have been put forward to improve the therapeutic development process in China and more novel therapies have been approved in recent years. It is important to develop and test novel therapies in China given differences in metabolism and tolerance compared to other populations.

Exploring the impact of patient-specific clinical features on osimertinib effectiveness in a real-world cohort of patients with EGFR mutated non-small cell lung cancer

Osimertinib is prescribed to patients with metastatic non-small cell lung cancer (NSCLC) and a sensitizing EGFR mutation. Limited data exists on the impact of patient characteristics or osimertinib exposure on effectiveness outcomes. This was a Dutch, multicenter cohort study. Eligible patients were ≥18 years, with metastatic EGFRm+ NSCLC, receiving osimertinib. Primary endpoint was progression-free survival (PFS). Secondary endpoints included overall survival (OS) and safety. Kaplan-Meier analyses and multivariate Cox proportional hazard models were performed. In total, 294 patients were included. Primary EGFR-mutations were mainly exon 19 deletions (54%) and p.L858R point mutations (30%). Osimertinib was given in first-line (40%), second-line (46%) or beyond (14%), with median PFS 14.4 (95% CI: 9.4-19.3), 13.9 (95% CI: 11.3-16.1) and 8.7 months (95% CI: 4.6-12.7), respectively. Patients with low BMI (<20.0 kg/m2 ) had significantly shorter PFS/OS compared to all other subgroups. Patients with a high plasma trough concentration in steady state (Cmin,SS ; >271 ng/mL) had shorter PFS compared to a low Cmin,SS (<163 ng/mL; aHR 2.29; 95% CI: 1.13-4.63). A significant longer PFS was seen in females (aHR = 0.61, 95% CI: 0.45-0.82) and patients with the exon 19 deletion (aHR = 0.58, 95% CI: 0.36-0.92). A trend towards longer PFS was seen for TP53 wild-type patients, while age did not impact PFS. Patients with a primary EGFR exon 19 deletion had longer PFS, while a low BMI, male sex and a high Cmin,SS were indicative for shorter PFS and/or OS. Age was not associated with effectiveness outcomes of osimertinib.

Safety, tolerability, and pharmacokinetics of ibrexafungerp in healthy Chinese subjects: a randomized, double-blind, placebo-controlled phase 1 trial

Ibrexafungerp (code name in China: HS-10366) is a first-in-class and orally active triterpenoid antifungal agent with broad antifungal activity against Candida spp., Aspergillus spp., and other fungal pathogens. It was approved by the U.S. Food and Drug Administration for the treatment of vulvovaginal candidiasis. The study aimed to evaluate the safety, tolerability, and pharmacokinetic (PK) characteristics of oral ibrexafungerp in healthy Chinese adults. A single-center, randomized, double-blind, placebo-controlled single ascending dose (SAD, n = 42), and multiple ascending dose (MAD, n = 28) study was conducted in healthy Chinese subjects from March to October 2022. There were three cohorts in the SAD stage (300, 600, and 1,500 mg) and two cohorts in the MAD stage [450 mg once daily (QD) for 7 days; a loading dose of 750 mg twice daily (BID) for the first 2 days followed by a maintenance dose of 750 mg QD for consecutive 5 days]. Eligible participants in each cohort were randomly assigned in a 6:1 ratio to receive either ibrexafungerp or placebo orally. The primary objectives were to evaluate the safety and tolerability. The secondary objective was to evaluate PK parameters, including Cmax, AUC, and t1/2. A total of 70 healthy Chinese subjects were enrolled in the study. The mean (SD) age was 29.0 (6.32), and 55.7% were male. All treatment-emergent adverse events (TEAEs) were mild or moderate. There were no serious adverse events, and no subjects were discontinued from the study due to TEAEs. All TEAEs were recovered or resolved. The most common TEAEs were diarrhea, abdominal pain, and nausea. In the SAD stage, Cmax, and AUC increased in an approximately dose-proportional manner in the dose range of 300-1,500 mg. The mean t1/2 was within 18.29-21.30 hours. In the MAD stage, an accumulation of exposure (Cmax and AUC) was observed following multiple doses. This phase 1 study demonstrates a favorable safety, tolerability, and PK profile of ibrexafungerp in healthy Chinese subjects.

Safety, pharmacokinetics, and efficacy of belantamab mafodotin monotherapy in Japanese patients with relapsed or refractory multiple myeloma: DREAMM-11

Belantamab mafodotin, a B-cell maturation antigen-targeting antibody-drug conjugate (ADC), was investigated in Japanese patients with relapsed/refractory multiple myeloma in Part 1 of the phase I DREAMM-11 study. Patients who had received ≥ 2 prior lines of therapy including a proteasome inhibitor and immunomodulatory agent were eligible. Eight patients received belantamab mafodotin monotherapy at 2.5 mg/kg (n = 4) or 3.4 mg/kg (n = 4) by intravenous infusion every 3 weeks on day 1 of each cycle until disease progression or unacceptable toxicity. Primary objectives were tolerability and safety, and secondary objectives included pharmacokinetics (PK) and efficacy. The most common Grade ≥ 3 adverse event was thrombocytopenia/platelet count decreased (2.5 mg/kg cohort, 100% [4/4]; 3.4 mg/kg cohort, 75% [3/4]), and no dose-limiting toxicities were observed. Ocular events, including keratopathy findings, were observed in most patients (2.5 mg/kg cohort, 100% [4/4]; 3.4 mg/kg cohort, 75% [3/4]) and were managed with dose modifications. All resolved within the study period. Overall response rates were 50% (2/4) in the 2.5 mg/kg cohort and 25% (1/4) in the 3.4 mg/kg cohort. Although PK profiles in Japanese patients varied, individual exposures overlapped with previous results in Western populations. Belantamab mafodotin monotherapy was generally well-tolerated and demonstrated clinical activity at both doses.

Evaluation of the drug disposition of RO7049389 with in vitro data and human mass balance supported by physiologically based pharmacokinetic modelling

AIMS

RO7049389 (linvencorvir) is a developmental oral treatment for chronic hepatitis B virus infection. The aim of this work was to conduct mass balance (MB) and absolute bioavailability (BA) analyses in healthy volunteers, alongside in vitro evaluations of the metabolism of RO7049389 and a major circulating active metabolite M5 in human hepatocytes, and physiologically based pharmacokinetic (PBPK) modelling to refine the underlying drug disposition paradigm.

METHODS

Participants in the clinical study (MB: Caucasian, male, n = 6; BA: Caucasian and Asian, male and female, n = 16, 8 in each ethnic groups) received oral [14 C] or unlabelled RO7049389 (600/1000 mg) followed by 100 μg intravenous [13 C]RO7049389. Metabolic pathways with fractions metabolized-obtained from the in vitro incubation results of 10 μM [14 C]RO7049389 and 1 μM M5 with (long-term cocultured) human hepatocytes in the absence and presence of the cytochrome P450 3A4 (CYP3A4) inhibitor itraconazole-were used to complement the PBPK models, alongside the clinical MB and BA data.

RESULTS

The model performance in predicting the pharmacokinetic profiles of RO7049389 and M5 aligned with clinical observations in Caucasians and was also successfully applied to Asians. Accordingly, the drug disposition pathways for RO7049389 were postulated with newly characterized estimates of the fractions: biliary excretion by P-glycoprotein (~41%), direct glucuronidation via uridine 5'-diphosphoglucuronosyltransferase 1A3 (~11%), hexose conjugation (~6%), oxidation by CYP3A4 (~28%) and other oxidation reactions (~9%).

CONCLUSION

These results support the ongoing clinical development program for RO7049389 and highlight the broader value of PBPK and MB analyses in drug development.

Clinical outcomes of chemotherapy in cancer patients with different ethnicities

BACKGROUND

Choosing the most effective chemotherapeutic agent with safest side effect profile is a common challenge in cancer treatment. Although there are standardized chemotherapy protocols in place, protocol changes made after extensive clinical trials demonstrate significant improvement in the efficacy and tolerability of certain drugs. The pharmacokinetics, pharmacodynamics, and tolerance of anti-cancer medications are all highly individualized. A driving force behind these differences lies within a person's genetic makeup.

RECENT FINDINGS

Pharmacogenomics, the study of how an individual's genes impact the processing and action of a drug, can optimize drug responsiveness and reduce toxicities by creating a customized medication regimen. However, these differences are rarely considered in the initial determination of standardized chemotherapeutic protocols and treatment algorithms. Because pharmacoethnicity is influenced by both genetic and nongenetic variables, clinical data highlighting disparities in the frequency of polymorphisms between different ethnicities is steadily growing.  Recent data suggests that ethnic variations in the expression of allelic variants may result in different pharmacokinetic properties of the anti-cancer medication. In this article, the clinical outcomes of various chemotherapy classes in patients of different ethnicities were reviewed.

CONCLUSION

Genetic and nongenetic variables contribute to the interindividual variability in response to chemotherapeutic drugs. Considering pharmacoethnicity in the initial determination of standard chemotherapeutic protocols and treatment algorithms can lead to better clinical outcomes of patients of different ethnicities.

The Application of Virtual Therapeutic Drug Monitoring to Assess the Pharmacokinetics of Imatinib in a Chinese Cancer Population Group

PURPOSE

Imatinib is used in gastrointestinal stromal tumours (GIST) and chronic myeloid leukaemia (CML). Oncology patients demonstrate altered physiology compared to healthy adults, e.g. reduced haematocrit, increased α-1 acid glycoprotein, decreased albumin and reduced glomerular filtration rate (GFR), which may influence imatinib pharmacokinetics. Given that Chinese cancer patients often report raised imatinib plasma concentrations and wider inter-individual variability reported in trough concentration when compared to Caucasian cancer patients, therapeutic drug monitoring (TDM) has been advocated.

METHOD

This study utilised a previously validated a Chinese cancer population and assessed the impact of imatinib virtual-TDM in Chinese and Caucasian cancer populations across a dosing range from 200-800 mg daily.

RESULTS

Staged dose titration to 800 mg daily, resulted in recapitulation to within the target therapeutic range for 50 % (Chinese) and 42.1% (Caucasian) subjects possessing plasma concentration < 550 ng/mL when dosed at 400 mg daily. For subjects with plasma concentrations >1500 ng/mL when dosed at 400 mg daily, a dose reduction to 200 mg once daily was able to recover 67 % (Chinese) and 87.4 % (Caucasian) patients to the target therapeutic range.

CONCLUSION

Virtual TDM highlights the benefit of pharmacokinetic modelling to optimising treatments in challenging oncology population groups.

A comparison of clinical characteristics of psychiatric inpatients in three hospitals from Western China and America

BACKGROUND

Different countries have differences in social and cultural context and health system, which may affect the clinical characteristics of psychiatric inpatients. This study was the first to compare cross-cultural differences in the clinical characteristics of psychiatric inpatients in three hospitals from Western China and America.

METHODS

Overall, 905 and 1318 patients from three hospitals, one in America and two in Western China, respectively, were included. We used a standardised protocol and data collection procedure to record inpatients' sociodemographic and clinical characteristics.

RESULTS

Significant differences were found between hospitals from the two countries. Positive symptoms were the main reason for admission in the Chinese hospitals, while reported suicide and self-injury symptoms more frequently led to hospital admission in America. Moreover, there were more inpatients with combined substance abuse in the American hospital (97.6% vs. 1.9%, P < 0.001). The length of stay (LOS) in America was generally shorter than in China (10.5 ± 11.9 vs. 20.7 ± 13.4, P < 0.001). The dosage of antipsychotic drugs used in the American hospital was higher than in China (275.1 ± 306.9 mg vs. 238.3 ± 212.5 mg, P = 0.002). Regression analysis showed that male sex, older age, retirees, being admitted because of physical symptoms, and using higher doses of antipsychotic drugs were significantly associated with longer hospitalisation in the American hospital (P < 0.05). Comparatively, patients who were divorced, experiencing suicidal ideation, admitted involuntarily, admitted because of physical, depression, or anxiety symptoms, and using higher doses of antipsychotic drugs had longer hospitalisation in Chinese hospitals (P < 0.05).

CONCLUSION

Significant variations in clinical characteristics of inpatients were found between hospitals from Western China and America. The LOS in Chinese hospitals was significantly longer, but patients used higher doses of antipsychotic drugs in the American hospital. Admission due to physical symptoms and the use of higher dosage drugs were related to longer LOS in both countries.

The west meets the east - A need for a renaissance in brain, behavior, and immunity research

Psychoneuroimmunology (PNI)-the burgeoning concept in recent years, can potentially contribute to developing effective treatments for mental health disorders. Despite the advancement in the modern pharmacological approach for mental disorders, especially Western medicine attributed explicitly to interacting with a specific target has given rise to unmet needs, and treatment failure has led to the proliferation and exploration of traditional and alternative therapies. As research into these exciting under-explored traditional treatment approaches continues to evolve at an unprecedented pace, the need to gain vital insights into the potentiality and mechanism of action in neuropsychiatric disorders has resulted in the current Special Issue. This Special Issue is devoted to psychoneuroimmunology, focusing on introducing the recent advances with traditional and alternative medications in East Asia at the interface of immunology, neurosciences, molecular psychiatry and behavioural medicine neurosciences.

Effects of food and race on the pharmacokinetics of lazertinib in healthy subjects and patients with EGFR mutation-positive advanced non-small cell lung cancer

OBJECTIVES

Lazertinib is a potent, irreversible, brain-penetrant, mutant-selective, and wild type-sparing third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor indicated for advanced non-small cell lung cancer (NSCLC). The study aimed to evaluate the effects of food and race on the pharmacokinetics (PK) of lazertinib from a healthy volunteer trial and PK data from NSCLC patients with EGFR mutation.

MATERIALS AND METHODS

An open-label, single-dose, two-period, single-sequence crossover study was conducted in healthy subjects with two race groups (non-Asian and Asian). Subjects orally received a single dose of lazertinib 240 mg in fasted and fed state (high-fat meal) in each period separated by a 21-day washout. An open-label, multicenter, phase 1/2 study was conducted in Asian and non-Asian patients with NSCLC. Patients were given oral lazertinib 20-320 mg once daily in fasted state continuously in 21-day cycles. PK parameters were evaluated using non-compartmental analysis.

RESULTS

A total of 24 healthy subjects (12 non-Asians and 12 Asians) and 52 NSCLC patients (22 non-Asians and 30 Asians) were evaluated. The change in the overall systemic exposure of lazertinib at fed state was less than 15%. Non-Asians showed 58-76% of the systemic exposure than Asians in healthy subjects. In contrast, there were no significant differences in systemic exposure by race both after single and multiple doses among NSCLC patients.

CONCLUSION

Lazertinib can be taken with or without food considering the comparable systemic exposures related to food. Although effect of race was not consistent across studies, there was no evidence for dose adjustment based on race.

Evaluation of Ethnicity Effect on Intranasal Esketamine Pharmacokinetics by Population Pharmacokinetic Modeling Using Data From a Japanese Phase 2b Study

Esketamine is used for the treatment of treatment-resistant depression in many countries. A population pharmacokinetic (popPK) model of esketamine and its metabolite (noresketamine) has been previously developed, which included Asian race and Japanese ethnicity as covariates on their exposures. The present study aimed to update the popPK model by adding new data from a phase 2b study in Japanese patients and reassess intrinsic and extrinsic factors on esketamine and noresketamine exposures. The updated model identified the effects of body weight on the fraction of the esketamine dose absorbed in the nasal cavity and elimination rate constant of esketamine, and Asian race on the apparent clearance of noresketamine. The model predicted that an increase of 30 kg of body weight would decrease esketamine exposures by ≈20%. Noresketamine exposures would be affected by Asian race and body weight. However, those newly identified covariates were not considered to have clinically relevant impacts, and therefore dose adjustments were not necessary. In conclusion, the popPK model of esketamine and noresketamine was successfully updated and suggested that interindividual variability of esketamine exposures can be better explained by body weight, rather than by race/ethnicity. The new findings obtained in this study should be useful information for the further development of esketamine and for clinical practice in the future.

Statins and the Risk of Gastric Cancer: A Systematic Review and Meta-Analysis

Previous epidemiological studies have reported that the use of statins is associated with a decreased risk of gastric cancer, although the beneficial effects of statins on the reduction of gastric cancer remain unclear. Therefore, we conducted a systematic review and meta-analysis to investigate the association between the use of statins and the risk of gastric cancer. Electronic databases such as PubMed, EMBASE, Scopus, and Web of Science were searched between 1 January 2000 and 31 August 2022. Two authors used predefined selection criteria to independently screen all titles, abstracts, and potential full texts. Observational studies (cohort and case-control) or randomized control trials that assessed the association between statins and gastric cancer were included in the primary and secondary analyses. The pooled effect sizes were calculated using the random-effects model. The Meta-analysis of Observational Studies in Epidemiology (MOOSE) reporting guidelines were followed to conduct this study. The total sample size across the 20 included studies was 11,870,553. The use of statins was associated with a reduced risk of gastric cancer (RRadjusted: 0.72; 95%CI: 0.64−0.81, p < 0.001). However, the effect size of statin use on the risk of gastric cancer was lower in Asian studies compared to Western studies (RRAsian: 0.62; 95%CI: 0.53−0.73 vs. RRwestern: 0.88; 95%CI: 0.79−0.99). These findings suggest that the use of statins is associated with a reduced risk of gastric cancer. This reverse association was even stronger among Asian people than Western individuals.

Effect of Dronedarone in the Treatment of Atrial Fibrillation in the Asian Population: Post Hoc Analysis of the ATHENA Trial

PURPOSE

Limited data are available on the impact of dronedarone treatment in Asian patients with atrial fibrillation (AF) or atrial flutter (AFL). This post hoc analysis evaluated the efficacy and safety of dronedarone compared with placebo in populations from Asian and non-Asian regions randomized in the ATHENA trial (A Placebo-Controlled, Double-blind, Parallel Arm Trial to Assess the Efficacy of Dronedarone 400 mg BID for the Prevention of CV Hospitalization or Death From Any Cause in Patients With AF/AFL).

METHODS

Time to first hospitalization for cardiovascular events or death from any cause (primary outcome) and time to first AF/AFL event recurrence (secondary outcome) were analyzed by Kaplan-Meier curves and Cox proportional hazards regression.

FINDINGS

The risk of experiencing the primary composite outcome was significantly lower in the dronedarone-treated patients in both the Asian (hazard ratio = 0.541; 95% CI, 0.320-0.914]) and non-Asian (hazard ratio = 0.768; 95% CI, 0.696-0.848) populations than in the placebo-treated patients. The median time to the first AF/AFL event recurrence was longer in the dronedarone-treated population than in the placebo-treated populations: 183 vs 92 days (P = 0.165) in the Asian population and 534 vs 196 days (P < 0.001) in the non-Asian population. Treatment-emergent adverse events in Asian (81.2% vs 78.4%) and non-Asian (71.4% vs 68.7%) populations and serious treatment-emergent adverse events in Asian (14.3% vs 15.7%) and non-Asian (20.3% vs 21.5%) patients were comparable in patients taking dronedarone compared with those taking placebo.

IMPLICATION

Efficacy and tolerability of dronedarone were consistent in the Asian population compared with the non-Asian population in the ATHENA trial. These finding may aid Asian health care professionals to select the appropriate first-line treatment for Asian patients with AF/AFL.

Adverse Drug Reactions in Relation to Clozapine Plasma Levels: A Systematic Review

Clozapine is the gold standard for treatment-resistant schizophrenia. Serious and even life-threatening adverse effects, mostly granulocytopenia, myocarditis, and constipation, are of great clinical concern and constitute a barrier to prescribing clozapine, thus depriving many eligible patients of a lifesaving treatment option. Interestingly, clozapine presents variable pharmacokinetics affected by numerous parameters, leading to significant inter- and intra-individual variation. Therefore, therapeutic drug monitoring of plasma clozapine levels confers a significant benefit in everyday clinical practice by increasing the confidence of the prescribing doctor to the drug and the adherence of the patient to the treatment, mainly by ensuring effective treatment and limited dose-related side effects. In the present systematic review, we aimed at identifying how a full range of adverse effects relates to plasma clozapine levels, using the Jadad grading system for assessing the quality of the available clinical evidence. Our findings indicate that EEG slowing, obsessive-compulsive symptoms, heart rate variability, hyperinsulinemia, metabolic syndrome, and constipation correlate to plasma clozapine levels, whereas QTc, myocarditis, sudden death, leucopenia, neutropenia, sialorrhea, are rather unrelated. Rapid dose escalation at the initiation of treatment might contribute to the emergence of myocarditis, or leucopenia. Strategies for managing adverse effects are different in these conditions and are discussed accordingly.

Cardio- and Neurotoxicity of Selected Anti-COVID-19 Drugs

Since December 2019, the novel coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has infected ~435 million people and caused ~6 million related deaths as of March 2022. To combat COVID-19, there have been many attempts to repurpose FDA-approved drugs or revive old drugs. However, many of the current treatment options have been known to cause adverse drug reactions. We employed a population-based drug screening platform using 13 human leukocyte antigen (HLA) homozygous human induced pluripotent cell (iPSC) lines to assess the cardiotoxicity and neurotoxicity of the first line of anti-COVID-19 drugs. We also infected iPSC-derived cells to understand the viral infection of cardiomyocytes and neurons. We found that iPSC-derived cardiomyocytes express the ACE2 receptor which correlated with a higher infection of the SARS-CoV-2 virus (r = 0.86). However, we were unable to detect ACE2 expression in neurons which correlated with a low infection rate. We then assessed the toxicity of anti-COVID-19 drugs and identified two cardiotoxic compounds (remdesivir and arbidol) and four neurotoxic compounds (arbidol, remdesivir, hydroxychloroquine, and chloroquine). These data show that this platform can quickly and easily be employed to further our understanding of cell-specific infection and identify drug toxicity of potential treatment options helping clinicians better decide on treatment options.

Population Pharmacokinetics of Abrocitinib in Healthy Individuals and Patients with Psoriasis or Atopic Dermatitis

BACKGROUND AND OBJECTIVE

Abrocitinib is a Janus kinase 1 inhibitor in development for the treatment of atopic dermatitis (AD). This work characterized orally administered abrocitinib population pharmacokinetics in healthy individuals, patients with psoriasis, and patients with AD and the effects of covariates on abrocitinib exposure.

METHODS

Abrocitinib concentration measurements (n = 6206) from 995 individuals from 11 clinical trials (seven phase I, two phase II, and two phase III) were analyzed, and a non-linear mixed-effects model was developed. Simulations of abrocitinib dose proportionality and steady-state accumulation of maximal plasma drug concentration (Cmax) and area under the curve (AUC) were conducted using the final model.

RESULTS

A two-compartment model with parallel zero- and first-order absorption, time-dependent bioavailability, and time- and dose-dependent clearance best described abrocitinib pharmacokinetics. Abrocitinib coadministration with rifampin resulted in lower exposure, whereas Asian/other race coadministration with fluconazole and fluvoxamine, inflammatory skin conditions (psoriasis/AD), and hepatic impairment resulted in higher exposure. After differences in body weight are accounted for, Asian participants demonstrated a 1.43- and 1.48-fold increase in Cmax and AUC, respectively. The overall distribution of exposures (Cmax and AUC) was similar in adolescents and adults after accounting for differences in total body weight.

CONCLUSIONS

A population pharmacokinetics model was developed for abrocitinib that can be used to predict abrocitinib steady-state exposure in the presence of drug-drug interaction effects or intrinsic patient factors. Key covariates in the study population accounting for variability in abrocitinib exposures are Asian race and adolescent age, although these factors are not clinically meaningful.

CLINICAL TRIAL NUMBERS

NCT01835197, NCT02163161, NCT02201524, NCT02780167, NCT03349060, NCT03575871, NCT03634345, NCT03637790, NCT03626415, NCT03386279, NCT03937258.

Population-based high-throughput toxicity screen of human iPSC-derived cardiomyocytes and neurons

In this study, we establish a population-based human induced pluripotent stem cell (hiPSC) drug screening platform for toxicity assessment. After recruiting 1,000 healthy donors and screening for high-frequency human leukocyte antigen (HLA) haplotypes, we identify 13 HLA-homozygous "super donors" to represent the population. These "super donors" are also expected to represent at least 477,611,135 of the global population. By differentiating these representative hiPSCs into cardiomyocytes and neurons we show their utility in a high-throughput toxicity screen. To validate hit compounds, we demonstrate dose-dependent toxicity of the hit compounds and assess functional modulation. We also show reproducible in vivo drug toxicity results using mouse models with select hit compounds. This study shows the feasibility of using a population-based hiPSC drug screening platform to assess cytotoxicity, which can be used as an innovative tool to study inter-population differences in drug toxicity and adverse drug reactions in drug discovery applications.

Long-term Safety and Efficacy of Esketamine Nasal Spray Plus an Oral Antidepressant in Patients with Treatment-resistant Depression- an Asian Sub-group Analysis from the SUSTAIN-2 Study

Objective

To evaluate the long-term safety and efficacy of intranasal esketamine in patients with treatment-resistant depression from the Asian subgroup of the SUSTAIN-2 study.

Methods

SUSTAIN-2 was a phase 3, open-label, single-arm, multicenter study comprising a 4-week screening, 4-week induction, 48-week optimization/maintenance, and 4-week follow-up (upon esketamine discontinuation) phase. Patients with treatment-resistant depression received esketamine plus an oral antidepressant during the treatment period.

Results

The incidence of ≥ 1 serious treatment-emergent adverse event (TEAE) among the 78 subjects from the Asian subgroup (Taiwan 33, Korea 26, Malaysia 19) was 11.5% (n = 9); with no fatal TEAE. 13 Asian patients (16.7%) discontinued esketamine due to TEAEs. The most common TEAEs were dizziness (37.2%), nausea (29.5%), dissociation (28.2%), and headache (21.8%). Most TEAEs were mild to moderate in severity, transient and resolved on the same day. Upon discontinuation of esketamine, no trend in withdrawal symptoms was observed to associate long-term use of esketamine with withdrawal syndrome. There were no reports of drug seeking, abuse, or overdose. Improvements in symptoms, functioning and quality of life, occurred during in the induction phase and were generally maintained through the optimization/maintenance phases of the study.

Conclusion

The safety and efficacy of esketamine in the Asian subgroup was generally consistent with the total SUSTAIN-2 population. There was no new safety signal and no indication of a high potential for abuse with the long-term (up to one year) use of esketamine in the Asian subgroup. Most of the benefits of esketamine occurred early during the induction phase.

Pharmacokinetics, Safety, and Tolerability of Single and Multiple Doses of Isavuconazonium Sulfate in Healthy Adult Japanese Subjects

Isavuconazonium sulfate is the water‐soluble prodrug of the novel, broad‐spectrum, triazole antifungal agent isavuconazole. This was a first‐in‐Japanese study assessing the pharmacokinetics, safety, and tolerability of isavuconazonium sulfate. The study was conducted in 2 parts: part 1 (single ascending dose; 100‐, 200‐, and 400‐mg equivalent of isavuconazole oral or intravenous administration); and part 2 (multiple doses for 16 days; 200‐mg equivalent of isavuconazole oral or intravenous administration; once‐daily administration with a loading regimen every 8 hours for the first 48 hours). A total of 60 and 16 subjects were randomized in part 1 and part 2, respectively. Observed clearance was lower in this study compared to what was previously reported in predominantly White populations and similar to clearance in non‐Japanese Asian populations. The range of the plasma isavuconazole concentration in this study was within the range of the pivotal phase 3 study, with no relationship between isavuconazole exposure and either efficacy or safety. There were no serious adverse events, and all reported treatment‐emergent adverse events were of mild intensity. This study confirmed that isavuconazonium sulfate was safe and well tolerated in healthy adult Japanese subjects.

The effect of oral diabetes medications on glycated haemoglobin (HbA1c) in Asians in primary care: a retrospective cohort real-world data study

BACKGROUND

Clinical trials have demonstrated that initiating oral anti-diabetic drugs (OADs) significantly reduce glycated hemoglobin (HbA1c) levels. However, variability in lifestyle modifications and OAD adherence impact on their actual effect on glycemic control. Furthermore, evidence on dose adjustments and discontinuation of OAD on HbA1c is lacking. This study aims to use real-world data to determine the effect of OAD initiation, up-titration, down-titration, and discontinuation on HbA1c levels, among Asian patients managed in primary care.

METHODS

A retrospective cohort study over a 5-year period, from Jan 2015 to Dec 2019 was conducted on a cohort of multi-ethnic adult Asian patients with clinical diagnosis of type 2 diabetes mellitus (T2DM) managed by a network of primary care clinics in Singapore. Nine OADs from five different classes (biguanides, sulphonyurea, dipeptidyl peptidase-4 [DPP-4] inhibitors, sodium-glucose cotransporter-2 [SGLT-2] inhibitors, and alpha-glucosidase inhibitors) were evaluated. Patients were grouped into "No OAD", "Non-titrators," and "Titrators" cohorts based on prescribing patterns. For the "Titrators" cohort, the various OAD titrations were identified. Subsequently, a descriptive analysis of HbA1c values before and after each titration was performed to compute a mean difference for each unique titration identified.

RESULTS

Among the cohort of 57,910 patients, 43,338 of them had at least one OAD titration, with a total of 76,990 pairs of HbA1c values associated with an OAD titration. There were a total of 206 unique OAD titrations. Overall, initiation of OADs resulted in a reduction of HbA1c by 3 to 12 mmol/mol (0.3 to 1.1%), respectively. These results were slightly lower than those reported in clinical trials of 6 to 14 mmol/mol (0.5 to 1.25%). The change of HbA1c levels due to up-titration, down-titration, and discontinuation were -1 to -8 mmol/mol (-0.1 to -0.7%), +1 to 7 mmol/mol (+0.1 to +0.6%), and +2 to 11 mmol/mol (+0.2 to +1.0%), respectively. The HbA1c lowering effect of initiating newer OADs, namely DPP-4 inhibitors and SGLT-2 inhibitors was 8 to 11 mmol/mol (0.7 to 0.9%) and 7 to 11 mmol/mol (0.6 to 1.0%), respectively.

CONCLUSION

The real-world data on Asians with T2DM in this study show that the magnitudes of OAD initiation and dose titration are marginally lower than the results from clinical trials. During shared decision-making in selecting treatment options, the results enable physicians to communicate realistic expectation of the effect of oral medications on the glycemic control of their patients in primary care.

Comparative efficacy of fixed-dose statin and antihypertensive agent combinations: A network meta-analysis of randomized controlled trials

BACKGROUND

The concurrent administration of statins and antihypertensive agents has been associated with improved cardiovascular outcomes, although the optimal fixed-dose combination remains unclear. This meta-analysis aims to compare the blood pressure and lipid-lowering effects of various statin and antihypertensive drug combinations.

METHODS

PubMed, Scopus, Web of Science, CENTRAL and Clinicaltrials.gov were systematically searched from inception to 20 March 2021. Randomized controlled trials evaluating the effects of statin-antihypertensive agent combinations on systolic blood pressure or serum lipids were held eligible. A random-effects frequentist model was applied to provide estimates of mean difference of percentage change.

RESULTS

Overall, 18 studies were included, comprising 4450 patients. Compared to statin monotherapy no significant difference in the percentage change of low-density lipoprotein cholesterol was achieved by adding any antihypertensive agent. Compared to amlodipine monotherapy, the addition of moderate-intensity statin resulted in a significantly greater percentage reduction of systolic blood pressure (-2.22%, 95% confidence intervals: [-3.82 to -0.62]). Combined high-intensity statin and amlodipine lead to significant increase of high-density lipoprotein cholesterol (8.34%, 95% confidence intervals: [0.73 to 15.95]), while effective triglyceride reduction was achieved by adding amlodipine and telmisartan to high-intensity statin (-14.68%, 95% confidence intervals: [-28.48 to -0.89]). No significant difference of adverse effects was observed.

CONCLUSION

The present network meta-analysis suggests that the administration of fixed-dose combinations of statins and antihypertensive agents is safe and effective in reducing blood pressure and serum lipids. The optimal dosing strategy to prevent cardiovascular events remains to be determined.

Population Pharmacokinetics of Meropenem in Critically Ill Korean Patients and Effects of Extracorporeal Membrane Oxygenation

Limited studies have investigated population pharmacokinetic (PK) models and optimal dosage regimens of meropenem for critically ill adult patients using the probability of target attainment, including patients receiving extracorporeal membrane oxygenation (ECMO). A population PK analysis was conducted using non-linear mixed-effect modeling. Monte Carlo simulation was used to determine for how long the free drug concentration was above the minimum inhibitory concentration (MIC) at steady state conditions in patients with various degrees of renal function. Meropenem PK in critically ill patients was described using a two-compartment model, in which glomerular filtration rate was identified as a covariate for clearance. ECMO did not affect meropenem PK. The simulation results showed that the current meropenem dosing regimen would be sufficient for attaining 40%fT_>MIC for Pseudomonas aeruginosa at MIC ≤ 4 mg/L. Prolonged infusion over 3 h or a high-dosage regimen of 2 g/8 h was needed for MIC > 2 mg/L or in patients with augmented renal clearance, for a target of 100%fT_>MIC or 100%fT_>4XMIC. Our study suggests that clinicians should consider prolonged infusion or a high-dosage regimen of meropenem, particularly when treating critically ill patients with augmented renal clearance or those infected with pathogens with decreased in vitro susceptibility, regardless of ECMO support.

Population pharmacokinetic analysis of ulotaront in subjects with schizophrenia

Ulotaront (SEP-363856) is a trace amine-associated receptor 1 agonist with 5-HT1A agonist activity in phase III development for the treatment of schizophrenia. The efficacy of ulotaront is not mediated by blockade of D2 or 5-HT2A receptors. The aim of this study was to evaluate the population pharmacokinetics (PopPKs) of ulotaront in adult subjects using pooled data from seven phase I studies, one phase II acute study, and one 6-month extension study. Single and multiple (up to 7 days) oral doses (5-150 mg/day) were studied in both healthy adult subjects (with intensive serial plasma sampling) and adult patients with schizophrenia (some with intensive and some with sparse plasma sampling). Ulotaront was well-absorbed and exhibited dose-proportionality in doses ranging from 10 to 100 mg, in mean maximum concentration, area under the concentration-time curve, and minimum concentration. Moderate interindividual variability was observed in concentration-time profiles. The estimated median time to maximal concentration was 2.8 h and the median effective half-life was 7 h, corresponding to an exposure accumulation ratio of 1.10 at steady-state with daily dosing. There was no indication of time-dependent changes in PKs after up to 12 weeks of daily dose administration. No clinically meaningful effects on ulotaront PK parameters were observed based on race, age, sex, formulation (capsule or tablet), or clinical status (healthy volunteer vs. patient with schizophrenia); body weight was the only meaningful covariate.

Ethnic Sensitivity Study of the Extrafine, Single-Inhaler, Triple Therapy Beclomethasone Dipropionate, Formoterol Fumarate, and Glycopyrronium Bromide Pressurized Metered Dose Inhaler in Japanese and Caucasian Healthy Individuals: A Randomized, Double-Blind, Single-Dose Crossover Study

PURPOSE

A number of single-inhaler, fixed-dose, triple combinations are available for the management of chronic obstructive pulmonary disease and/or asthma. One of these is the extrafine formulation beclomethasone dipropionate, formoterol fumarate, glycopyrronium bromide (BDP/FF/GB). Given that differences in ethnicity can result in differences in systemic exposure, we evaluated the relative pharmacokinetic (PK) profiles of BDP/FF/GB in Japanese vs Caucasian healthy volunteers to assess the need for dose adjustment.

METHODS

This randomized, double-blind, single-dose, 4-way crossover study recruited healthy men and women 20 to 55 years of age; for each Japanese person a Caucasian was enrolled who matched in terms of sex, age, and weight. Study treatments included BDP/FF/GB 200/12/25 and 400/12/25 μg (therapeutic), 800/48/100 μg (supratherapeutic), and placebo. PK blood samples were taken up to 24 hours for evaluation of BDP, beclomethasone 17-monopropionate (B17MP, an active metabolite of BDP), and formoterol and up to 48 h for GB. The primary objective was to characterize the PK profiles of BDP, FF, and GB after administration of a single dose of BDP/FF/GB in Caucasian and Japanese healthy volunteers in terms of the AUC_0-t and C_max of B17MP, formoterol, and GB.

FINDINGS

Of the 32 recruited participants (16 Japanese and 16 Caucasian ), 30 completed the study. A clear plasma exposure dose-response relationship was found for all 4 molecules. B17MP C_max geometric mean ratios for Japanese vs Caucasian participants for the 3 study treatments ranged from 1.17 to 1.26, and AUC_0-t ratios ranged from 1.16 to 1.22; thus, the findings were comparable between the ethnicities. Formoterol exposure was higher in Japanese than Caucasian participants (C_max, 1.22-1.53; AUC_0-t, 1.23-1.40). The GB C_max with BDP/FF/GB 400/12/25 μg (1.09) and AUC_0-t values for all three doses (0.98-1.17) were comparable in the 2 populations, but C_max with 200/12/25 and 800/48/100 μg were higher in Japanese participants (1.32 and 1.42, respectively). Pharmacodynamic (cortisol, potassium, glucose, blood pressure, heart rate, and QT interval with the Fridericia correction) and safety profile results were similar in the 2 ethnicities, with most patients not experiencing any adverse events.

IMPLICATIONS

Exposure to BDP/FF/GB pressurized metered dose inhaler at therapeutic and supratherapeutic doses was associated with higher plasma levels in Japanese versus Caucasian healthy volunteers. These PK differences did not translate into meaningful differences in the safety or pharmacodynamic parameters assessed in this study and were consistent with the results of other long-term (52-week) published studies. Dose adjustments in Japanese people are not deemed necessary. CLINICALTRIALS.

GOV IDENTIFIER

NCT03859414.

Assessment of the Utility of Physiologically-based Pharmacokinetic Model for prediction of Pharmacokinetics in Chinese and Japanese Populations

The objective for the present analyses was to evaluate the utility of physiologically-based pharmacokinetic (PBPK) modeling for prediction of the pharmacokinetics (PK) in Chinese and Japanese populations with a panel of Pfizer internal compounds. Twelve compounds from Pfizer internal development pipeline with available Westerner PK data and available PK data in at least one of the subpopulations of Japanese and Chinese populations were identified and included in the current analysis. These selected compounds represent various elimination pathways across different therapeutic areas. The Simcyp® PBPK simulator was used to develop and verify the PBPK models of individual compounds. The developed models for these compounds were verified by using the clinical PK data in Westerners. The verified PBPK models were further used to predict the PK of these compounds in Chinese and Japanese populations and the predicted PK parameters were compared with the observed PK parameters. Ten of the 12 compounds had PK data in Chinese, and all the 12 compounds had PK data in Japanese. In general, the PBPK models performed well in predicting PK in Chinese and Japanese, with 8 of 10 drugs in Chinese and 7 of 12 drugs in Japanese has AAFE values less than 1.25-fold. PBPK-guided predictions of the relative PK difference were successful for 75% and 50%, respectively, between Chinese and Western and between Japanese and Western of the tested drugs using 0.8-1.25 as criteria. In conclusion, well verified PBPK models developed using data from Westerners can be used to predict the PK in Chinese and Japanese populations.

Pharmacokinetics and safety of liposomal bupivacaine after local infiltration in healthy Chinese adults: a phase 1 study

Background

Liposomal bupivacaine (LB) is a long-acting formulation of bupivacaine. The safety and efficacy of LB has been demonstrated across surgical procedures. However, pharmacokinetic (PK) parameters and safety of LB in the Chinese population have not been assessed.

Methods

In this single-arm, single center, phase 1, open-label study, PK and safety of local infiltration with LB 266 mg were assessed in healthy Chinese adults. Eligible participants were aged 18 to 55 years with biologic parents and grandparents of Chinese ethnicity, in generally good health (i.e., no clinically significant abnormalities), and with a body mass index (BMI) 19.0 to 24.0 kg/m² (inclusive) and body weight ≥ 50 kg.

Results

Participants (N = 20) were predominantly men (80 %); mean age was 32 years; and mean BMI was 21.8 kg/m². After LB administration, mean plasma levels of bupivacaine rapidly increased during the first hour and continued to increase through 24 h; plasma levels then gradually decreased through 108 h followed by a monoexponential decrease through 312 h. Geometric mean maximum plasma concentration was 170.9 ng/mL; the highest plasma bupivacaine concentration detected in any participant was 374.0 ng/mL. Twenty-two treatment-emergent adverse events were reported (mild, n = 21; moderate, n = 1).

Conclusions

After single-dose administration of LB, PK measures were similar to a previously reported profile in US adults. The highest observed peak plasma concentration of bupivacaine was several-fold below the plasma concentration threshold accepted as being associated with neurotoxicity or cardiotoxicity (2000–4000 ng/mL). These data support that LB is well tolerated and safe in individuals of Chinese descent.

Trial registration

NCT04158102 (ClinicalTrials.gov identifier), Date of registration: November 5, 2019.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12871-021-01407-5.

Comparison of Pain Score and Complications Following Acetaminophen and Pethidine Injection During Vaginal Delivery: A Double-blind Clinical Trial

Objectives

Recently, intravenous acetaminophen has been introduced as an intervention with analgesic potential similar to that of opioid analgesics in labor pain management. This study aimed to compare the pain score and maternal and neonatal complications following acetaminophen and pethidine injections during vaginal delivery.

Methods

This randomized, double-blind clinical trial was conducted on pregnant women during the first stage of delivery referred to Ghaem and Omolbanin Hospitals in Mashhad, Iran, from March to December 2017. The subjects were assigned randomly to one of two groups: acetaminophen and pethidine. The pain intensity was measured before and 15, 60, 120, 180, and 240 minutes after injection.

Results

The pain score and pain score changes showed no significant difference between the two groups at different times. The incidence of maternal complications during delivery and the first hour after delivery was not statistically significant between the two groups, but 15 minutes after injection, vomiting (p = 0.001), nausea (p = 0.001), and dizziness (p = 0.001) were significantly higher in the pethidine group. The mean one and five minutes Apgar scores were significantly higher in the acetaminophen group.

Conclusions

Intravenous acetaminophen led to fewer maternal complications than pethidine, especially during the first 15 minutes after injection and fewer neonatal complications, especially in the Apgar score.

Pharmacokinetics and safety evaluation of oral Palonosetron in Chinese healthy volunteers: A phase 1, open-label, randomized, cross-over study

PURPOSE

Palonosetron hydrochloride is a specific 5-HT3 receptor antagonist, used to prevent chemotherapy-induced nausea and vomiting (CINV), and is a known chemical entity currently registered in the oral and IV forms in several countries worldwide.

METHODS

Single-center, single-dose, 3-treatment, open-label, randomized, 3-period, phase-I cross-over study, conducted in 18 individuals (16 males and 2 females). The primary objective was to assess the pharmacokinetic profile of Palonosetron 0.25, 0.5 and 0.75mg, after a single, oral administration in Chinese male and female healthy volunteers.

RESULTS

After administration of a single oral dose of 0.25mg, 0.5mg, or 0.75mg palonosetron in Chinese male and female healthy subjects, plasma palonosetron concentrations reached maximum values (C_max) of 673 ± 151 pg/mL, 1330 ± 258 pg/mL, and 1990 ± 490 pg/mL, respectively, at 3-5 h (t_max). The plasma elimination half-life for 0.25, 0.5 and 0.75 mg of palonosetron was 41.8±9.72 hours, 44.6±8.59 hours and 42.3±8.51 hours, respectively. Single oral doses of 0.25mg, 0.5mg, or 0.75mg palonosetron were safe and well tolerated among all the 18 subjects involved.

CONCLUSIONS

The PK of palonosetron was found to be linear in the dose range of 0.25 to 0.75 mg. Oral palonosetron in doses up to 0.75 mg was well tolerated in healthy Chinese subjects. The PK and safety data obtained from this study were similar to previous phase I studies with IV palonosetron.

Disparities in Cardiovascular Research Output and Disease Outcomes among High-, Middle- and Low-Income Countries - An Analysis of Global Cardiovascular Publications over the Last Decade (2008-2017)

Background

Cardiovascular disease (CVD) is the leading cause of death and disability worldwide. Health research is crucial to managing disease burden. Previous work has highlighted marked discrepancies in research output and disease burden between high-income countries (HICs) and low- and lower-middle-income countries (LI-LMICs) and there is little data to understand whether this gap has bridged in recent years. We conducted a global, country level bibliometric analysis of CVD publications with respect to trends in disease burden and county development indicators.

Methods

A search filter with a precision and recall of 0.92 and 0.91 respectively was developed to extract cardiovascular publications from the Web of Science (WOS) for the years 2008-2017. Data for disease burden and country development indicators were extracted from the Global Burden of Disease and the World Bank database respectively.

Results

Our search revealed 847,708 CVD publications for the period 2008-17, with a 43.4% increase over the decade. HICs contributed 81.1% of the global CVD research output and accounted for 8.1% and 8.5% of global CVD DALY losses deaths respectively. LI-LMICs contributed 2.8% of the total output and accounted for 59.5% and 57.1% global CVD DALY losses and death rates.

Conclusions

A glaring disparity in research output and disease burden persists. While LI-LMICs contribute to the majority of DALYs and mortality from CVD globally, their contribution to research output remains the lowest. These data call on national health budgets and international funding support to allocate funds to strengthen research capacity and translational research to impact CVD burden in LI-LMICs.

LDL-cholesterol change and goal attainment following statin intensity titration among Asians in primary care: a retrospective cohort study

Background

Clinical trials have demonstrated that either initiating or up-titrating a statin dose substantially reduce Low-Density Lipoprotein-Cholesterol (LDL-C) levels. However, statin adherence in actual practice tends to be suboptimal, leading to diminished effectiveness. This study aims to use real-world data to determine the effect on LDL-C levels and LDL-C goal attainment rates, when selected statins are titrated in Asian patients.

Methods

A retrospective cohort study over a 5-year period, from April 2014 to March 2019 was conducted on a cohort of multi-ethnic adult Asian patients with clinical diagnosis of Dyslipidaemia in a primary care clinic in Singapore. The statins were classified into low-intensity (LI), moderate-intensity (MI) and high-intensity (HI) groups according to the 2018 American College of Cardiology and American Heart Association (ACC/AHA) Blood Cholesterol Guidelines. Patients were grouped into “No statin”, “Non-titrators” and “Titrators” cohorts based on prescribing patterns. For the “Titrators” cohort, the mean percentage change in LDL-C and absolute change in LDL-C goal attainment rates were computed for each permutation of statin intensity titration.

Results

Among the cohort of 11,499 patients, with a total of 266,762 visits, there were 1962 pairs of LDL-C values associated with a statin titration. Initiation of LI, MI and HI statin resulted in a lowering of LDL-C by 21.6% (95%CI = 18.9–24.3%), 28.9% (95%CI = 25.0–32.7%) and 25.2% (95%CI = 12.8–37.7%) respectively. These were comparatively lower than results from clinical trials (30 to 63%). The change of LDL-C levels due to up-titration, down-titration, and discontinuation were − 12.4% to − 28.9%, + 13.2% to + 24.6%, and + 18.1% to + 32.1% respectively. The improvement in LDL-C goal attainment ranged from 26.5% to 47.1% when statin intensity was up-titrated.

Conclusion

In this study based on real-world data of Asian patients in primary care, it was shown that although statin titration substantially affected LDL-C levels and LDL-C goal attainment rates, the magnitude was lower than results reported from clinical trials. These results should be taken into consideration and provide further insight to clinicians when making statin adjustment recommendations in order to achieve LDL-C targets in clinical practice, particularly for Asian populations.

Pharmacokinetics and Pharmacodynamics of the Dual Orexin Receptor Antagonist Daridorexant in Japanese and Caucasian Subjects

PURPOSE/BACKGROUND

Daridorexant is a dual orexin receptor antagonist in development for the treatment of sleep disorders. Thus far, it has not yet been studied in Japanese subjects. Study objectives were to evaluate the pharmacokinetics (PK), pharmacodynamics (PD), and safety of single- and multiple-dose administration of daridorexant in healthy Caucasian and Japanese subjects.

METHODS/PROCEDURES

This was a double-blind, placebo-controlled, randomized study. Subjects received once-daily doses of daridorexant (25 or 50 mg) or placebo for 5 days. Pharmacokinetics and safety were investigated using standard assessments. To assess PD effects, a battery of tests (saccadic peak velocity, body sway, adaptive tracking performance, and visual analog scales for alertness, mood, and calmness), known to be sensitive to sleep-promoting drugs was used.

FINDINGS/RESULTS

On day 1, PK variables were similar between Caucasian and Japanese subjects. On day 5, slight accumulation occurred in Japanese but not in Caucasian subjects, resulting in a higher maximum concentration (1403 vs 1006 ng/mL) and area under the curve (8256 vs 6306 ng·h/mL) at a dose of 50 mg, whereas values for time to maximum concentration and half-life were similar. Daridorexant dose-dependently reduced vigilance, attention, visuomotor coordination, and postural stability. Pharmacokinetic effects were detectable within 1 hour after drug administration and returned to baseline 4 to 8 hours postdose. Overall, Japanese showed slightly larger PD effects and reported more adverse events than Caucasians. The most frequently reported were somnolence, fatigue, and headache. Changes in other safety assessments were unremarkable.

IMPLICATIONS/CONCLUSIONS

The PK, PD, and safety profile of daridorexant were similar in Japanese and Caucasian subjects.

Pharmacogenomic information from CPIC and DPWG guidelines and its application on drug labels

There are several hurdles to overcome before implementing pharmacogenomics (PGx) in precision medicine. One of the hurdles is unawareness of PGx by clinicians due to insufficient pharmacogenomic information on drug labels. Therefore, it might be important to implement PGx that reflects pharmacogenomic information on drug labels, standard of prescription for clinicians. This study aimed to evaluate the level at which PGx was being used in clinical practice by comparing the Clinical Pharmacogenetics Implementation Consortium and Dutch Pharmacogenetics Working Group guidelines and drug labels of the US Food and Drug Administration (FDA) and the Korea Ministry of Food and Drug Safety (MFDS). Two PGx guidelines and drugs labels were scrutinized, and the concordance of the pharmacogenomic information between guidelines and drug labels was confirmed. The concordance of the label between FDA and MFDS was analyzed. In FDA labels, the number of concordant drug with guidelines was 24, while 13 drugs were concordant with MFDS labels. The number of drugs categorized as contraindication, change dose, and biomarker testing required was 7, 12 and 12 for the FDA and 8, 5 and 4 for the MFDS, respectively. The pharmacogenomic information of 9 drugs approved by both FDA and MFDS was identical. In conclusion, pharmacogenomic information on clinical implementation guidelines was limited on both FDA and MFDS labels because of various reasons including the characteristics of the guidelines and the drug labels. Therefore, more effort from pharmaceutical companies, academia and regulatory affairs needs to be made to implement pharmacogenomic information on drug labels.

Multiple-Dose Pharmacokinetics, Safety, and Tolerability of Aprocitentan, a Dual Endothelin Receptor Antagonist, in Healthy Japanese and Caucasian Subjects

Aprocitentan is an orally active dual endothelin receptor antagonist currently in development for treatment of difficult-to-control (resistant) hypertension. In phase 1 and 2 studies, aprocitentan has been characterized predominantly in Caucasian subjects. In this bridging, double-blind study, 20 healthy Japanese and Caucasian male and female subjects received 25 mg of aprocitentan or placebo once daily for 10 days and were monitored until 216 hours after the last dosing. The pharmacokinetics of aprocitentan were similar between ethnicities. At steady state, maximum plasma concentration was reached at 4 and 3 hours, and elimination half-life was 49.1 and 48.8 hours for Japanese and Caucasian subjects, respectively. The accumulation index was around 3 for both populations. Geometric means ratios for maximum plasma concentration and area under the plasma concentration-time curve during 1 dosing interval were around 1, with 90% confidence interval ranging from 0.87 to 1.30. Aprocitentan was safe and well tolerated in both groups. As no clinically relevant differences were found between Japanese and Caucasian subjects, it is unlikely that the pharmacokinetics of aprocitentan would differ significantly between Caucasian subjects and other ethnicities. Aprocitentan can therefore be administered at a dose level of up to 25 mg in any ethnicity without dose adjustment.

Phase I dose escalation study of BI 836826 (CD37 antibody) in patients with relapsed or refractory B-cell non-Hodgkin lymphoma

BI 836826 is a chimeric immunoglobulin G1 antibody targeting CD37, a tetraspanin transmembrane protein predominantly expressed on normal and malignant B cells. This phase I, open-label study used a modified 3 + 3 design to evaluate the safety, maximum tolerated dose (MTD), pharmacokinetics, and preliminary activity of BI 836826 in patients with relapsed/refractory B cell non-Hodgkin lymphoma (NHL; NCT01403948). Eligible patients received up to three courses comprising an intravenous infusion (starting dose: 1 mg) once weekly for 4 weeks followed by an observation period of 27 (Course 1, 2) or 55 days (Course 3). Patients had to demonstrate clinical benefit before commencing treatment beyond course 2. Forty-eight patients were treated. In the dose escalation phase (1-200 mg) involving 37 Caucasian patients, the MTD was 100 mg. Dose-limiting toxicities occurred in four patients during the MTD evaluation period, and included stomatitis, febrile neutropenia, hypocalcemia, hypokalemia, and hypophosphatemia. The most common adverse events were neutropenia (57%), leukopenia (57%), and thrombocytopenia (41%), and were commonly of grade 3 or 4. Overall, 18 (38%) patients experienced infusion-related reactions, which were mostly grade 1 or 2. Preliminary evidence of anti-tumor activity was seen; three patients responded to treatment, including one complete remission in a Korean patient with diffuse large B cell lymphoma. BI 836826 plasma exposure increased more than proportionally with increasing doses. BI 836826 demonstrated preliminary activity; the most frequent adverse events were hematotoxicity and infusion-related reactions which were manageable after amending the infusion schedule. Although BI 856826 will not undergo further clinical development, these results confirm CD37 as a valid therapeutic target in B cell NHL.

Pharmacokinetics of pertuzumab administered concurrently with trastuzumab in Chinese patients with HER2-positive early breast cancer

In the APHINITY study (NCT01358877, BIG 4-11/BO25126/TOC4939G), pertuzumab added to trastuzumab and chemotherapy significantly improved invasive disease-free survival as adjuvant treatment for patients with HER2-positive early breast cancer. The objective of this analysis was to assess the pharmacokinetics of pertuzumab in combination with trastuzumab in Chinese patients with early breast cancer. Samples for pertuzumab and trastuzumab pharmacokinetic analysis were taken from Chinese patients during cycle 1 of treatment and at steady-state in cycle 10. Noncompartmental analysis was used to estimate minimum and maximum serum concentrations (Cmax and Cmin), area under the concentration-time curve, clearance, and other pharmacokinetic parameters. In 15 patients, mean steady-state Cmax and Cmin pertuzumab serum concentrations (368 ± 177 μg/ml, and 122 ± 47 μg/ml, respectively) were numerically higher than observed previously in a pharmacokinetic analysis of the global population in APHINITY and in patients treated in the metastatic setting. The geometric mean ratio and corresponding 90% confidence interval for trastuzumab Cmax and Cmin in the presence (n = 15) or absence (n = 17) of pertuzumab were 104.6 (91.09-120) and 98.23 (84.58-114), respectively, indicating no apparent impact of pertuzumab on the pharmacokinetics of trastuzumab. Increases in pertuzumab Cmax and Cmin were not associated with an increase in adverse events. The APHINITY Chinese pharmacokinetic substudy analysis supports the dosing regimen for pertuzumab (840 mg loading dose followed by 420 mg maintenance doses every 3 weeks administered by intravenous infusion) in a Chinese HER2-positive early breast cancer patient population.

Statin intolerance: an updated, narrative review mainly focusing on muscle adverse effects

INTRODUCTION

Statins have been established as the standard of care for dyslipidemia and preventing cardiovascular diseases while posing few safety concerns. However, misconceptions about statin intolerance lead to their underuse, indicating a need to improve the understanding of the safety of this treatment.

AREAS COVERED

We searched PubMed and reviewed literatures related to statin intolerance published between February 2015 and February 2020. Important large-scale or landmark studies published before 2015 were also cited as key evidence.

EXPERT OPINION

Optimal lowering of low-density lipoprotein cholesterol with statins substantially reduces the risk of cardiovascular events. Muscle adverse events (AEs) were the most frequently reported AEs by statin users in clinical practice, but they usually occurred at a similar rate with statins and placebo in randomized controlled trials and had a spurious causal relationship with statin treatment. We proposed a rigorous definition for identifying true statin intolerance and present the criteria for defining different forms of muscle AEs and an algorithm for their management. True statin intolerance is uncommon, and every effort should be made to exclude false statin intolerance and ensure optimal use of statins. For the management of statin intolerance, statin-based approaches should be prioritized over non-statin approaches.

Impact of Ethnicity-Specific Hepatic Microsomal Scaling Factor, Liver Weight, and Cytochrome P450 (CYP) 1A2 Content on Physiologically Based Prediction of CYP1A2-Mediated Pharmacokinetics in Young and Elderly Chinese Adults

BACKGROUND

The vast majority of physiological and biological data required for physiologically based predictions are primarily available in Caucasians rather than other ethnic populations, which leads to a lack of confidence in the application of physiologically based pharmacokinetic (PBPK) modeling for ethnicity-specific prediction of pharmacokinetics in the Chinese population.

OBJECTIVES

In this study we recalibrate the system parameters of Chinese-specific PBPK modeling and explore for the first time the relative importance of ethnicity-specific microsomal protein per gram of liver (MPPGL), liver weight, and cytochrome P450 (CYP) 1A2 abundance to the projection of drug disposition mediated by CYP1A2 in young and elderly Chinese adults.

METHODS

Chinese MPPGL levels and associated variability were parameterized and incorporated for the first time into ethnicity-specific PBPK models for the Chinese adults. Parameterization of Chinese liver weights was also recalibrated on the basis of autopsy data from Chinese individuals (n = 4081) across the entire adult age range. Uncertainty surrounding the Chinese-specific CYP1A2 content has also been explored and clarified by conducting ethnicity-related PBPK simulations under different scenarios. Various ethnicity-related or 'what-if' scenarios for PBPK modeling were implemented to assess the predictive performance and explore the relative importance of ethnicity-specific MPPGL and liver weight to the projection of drug disposition mediated by CYP1A2 in terms of two typical CYP1A2 substrates, caffeine and theophylline, in young and elderly Chinese adults by comparing the predicted concentration-time data and associated pharmacokinetic parameter estimates with observations.

RESULTS

Compared with 0.85, the liver scalar of 0.9 generally produced more accurate liver weight levels in virtual Chinese peers. Additionally, simulated MPPGL levels on the basis of Caucasian data were not able to reflect the age-independent pattern observed in Chinese adults, dissimilar to that on the basis of Chinese-specific adult MPPGL data. The modeling Scenarios A and B provided similar predictions for theophylline pharmacokinetics in young Chinese adults across different age groups, while Scenario B provided the most accurate prediction for theophylline pharmacokinetics in elderly Chinese adults. However, the use of a stratified value of CYP1A2 content derived from a Han Chinese cohort with a small sample size instead of the pooled value of all Chinese cohorts involved regardless of Chinese sub-ethnicity resulted in inadequate prediction of CYP1A2-mediated pharmacokinetics in terms of caffeine and theophylline in either young or elderly Chinese subjects. Additionally, the impact of ethnic-specific MPPGL on predictive accuracy of theophylline pharmacokinetics in elderly Chinese subjects is more evident than that of liver weight.

CONCLUSION

We provided quantitative information pertaining to Chinese-specific levels of liver weight and MPPGL, and recalibrated these system parameters for PBPK modeling for young and elderly Chinese subjects. Uncertainty surrounding the Chinese-specific CYP1A2 content has also been clarified. PBPK modeling based on the recalibrated system parameters can accurately simulate CYP1A2-mediated pharmacokinetics in both young and elderly Chinese adults, particularly in elderly individuals.

Effects of methadone, opium tincture and buprenorphine maintenance therapies on thyroid function in patients with OUD

Various types of medications are used as maintenance therapies for substance use disorder; However, the side effects of these drugs are shown to restrict their use and increase the risk of relapse in patients. As a result, alternative maintenance therapies are tested in the hope for optimum therapy. Since opium tincture is a new and innovative maintenance treatment in Iran, we attempted to compare the therapeutic and side effects of opium tincture with two standard therapies, i.e., methadone and buprenorphine. Hence, thyroid function was tested in three methods of maintenance therapies with methadone, buprenorphine, and opium tincture in a cross-sectional study. In this study, 150 patients with the mean age of 51.63 ± 13.56 years and a history of opioid or opioid-derivatives use disorder, underwent the maintenance treatment with methadone, buprenorphine, and opium tincture at Bojnurd Addiction Treatment Centers in northeastern Iran. These patients were selected using convenience sampling. Then, they were placed into three treatment groups of methadone, buprenorphine, and opium tincture. The thyroid functionality was assessed with measuring TSH, fT4, fT3, T3RU, and Anti TPO, carried out in a reference laboratory. Finally, these data were analyzed by ANOVA using SPSS.16 software. The results showed that there was no significant difference in the average levels of TSH, fT3, fT4, and Anti TPO in these treatment groups; except for T3RU concentration, which was increased significantly in the opium tincture group as compared to the methadone treated group. Also, the frequency of fT4, and T3RU disorders demonstrated a significant change in three groups. The findings of the present study demonstrated that opium tincture in comparison with methadone could increase T3RU levels resulting in euthyroidism possibly through TBG.

Impact of Plasma Exposure of Statins and Their Metabolites With Major Adverse Cardiovascular Events in Chinese Patients With Coronary Artery Disease

The selection of optimum statin intensity is inconclusive, and the association of plasma exposure of statins and metabolites with major adverse cardiovascular events (MACEs) is unclear. This study sought to compare the effect of low (quartile 1), intermediate (quartiles 2 and 3), and high (quartile 4) plasma exposure of statins and metabolites on MACE, re-ischemia events and death in patients with coronary artery disease (CAD) at 5 years. A total of 1,644 patients in atorvastatin (AT) cohort and 804 patients in rosuvastatin (RST) cohort were included, and their plasma concentration of statins and metabolites was categorized as low-, mid-, or high-group. The association between the plasma levels of statins and metabolites and the incidence of primary endpoint in patients was assessed by Cox proportional hazard models. Intensive AT exposure (Q4 > 5.32 ng/ml) was significantly associated with increased risk of death compared with low (hazard ratio [HR]: 1.522; 95% confidence interval [CI]: 1.035–1.061; P = 0.0022) or moderate exposure (HR: 2.054; 95% CI: 1.348–3.130; P = 0.0008). This association was also found in AT’s five metabolites (all P < 0.01). In patients with RST treatment, moderate RST concentration (0.53–4.29 ng/ml) versus low concentration had a significantly lower risk of MACE and re-ischemia events. (HR: 0.532, 95% CI: 0.347–0.815, P = 0.0061 and HR: 0.505, 95% CI: 0.310–0.823, P = 0.0061, respectively). A higher plasma exposure of AT and metabolites has a significantly higher risk of death, and moderate RST exposure has a significantly lower risk of MACE and re-ischemia events in Chinese patients with CAD. The harms of high plasma exposure should be considered when prescribing statins to patients because it may be a risk factor for having poor prognosis in patients with CAD.

Thymic epithelial tumors: From biology to treatment

In the last few years, meaningful advances have been made in the knowledge of the biology of Thymic Epithelial Tumors (TETs). Data available suggest that in most cases, the different histological subtypes could be distinct biological entities, characterized by specific molecular aberrations, rather than representing a histological continuum of diseases. Recurrent gene mutations in Thymomas and Thymic Carcinoma have been identified, but we still do not know the exact role played by these mutations in TETs pathogenesis. Relevant new data are now available on the pathogenetic mechanisms underlying the association between TETs and autoimmune diseases that warrant further investigations for the potential therapeutic implications. The progress in knowledge of the molecular pathways involved in TETs pathogenesis, allowed to identify and to test target therapies potentially active in such diseases. Platinum-based chemotherapy remains the standard first line treatment for patients with advanced or metastatic TETs. However, some promising data have been reported on the activity of new target therapies, including anti-angiogenic drugs, Cycline Dependent Kinases and PI3K/mTOR inhibitors, as well as of Immune-checkpoint inhibitors. A number of new drugs and combinations are currently under evaluation. The efficacy of new drugs should be balanced with their toxicity profiles, in such complex patients that seem to be more susceptible to develop drug-related toxicities, in particular with immunotherapies.

Oral Ciprofloxacin Pharmacokinetics in Healthy Mexican Volunteers and Other Populations: Is There Interethnic Variability?

BACKGROUND

There is evidence that the pharmacokinetics of certain drugs in Mexicans may differ with respect to other ethnic groups. On the other hand, there is controversy about the existence of interethnic variability in the pharmacokinetics of ciprofloxacin.

AIM OF THE STUDY

To study oral ciprofloxacin pharmacokinetics in Mexicans at various dose levels and make comparisons with other populations in order to gain insight on interethnic variability.

METHODS

Healthy Mexican volunteers received oral ciprofloxacin as 250 mg and 500 mg immediate-release tablets or a 1,000 mg extended-release formulation. Plasma concentration against time curves were constructed, and pharmacokinetic parameters were compared with those reported for other populations.

RESULTS

Ciprofloxacin pharmacokinetics in Mexicans was linear and no significant differences between males and females were detected. When several populations were compared, it appeared that bioavailability in Mexicans was similar to that of Caucasians, being lower than that of Asians. These variations were attenuated when data were normalized by body weight.

CONCLUSIONS

Ciprofloxacin pharmacokinetics exhibit interethnic variability, Asians exhibiting an increased bioavailability with regard to Mexicans and Caucasians. Data suggest that these differences are due to body weight.

Pharmacokinetic Modeling, Simulation, and Development of a Limited Sampling Strategy of Cycloserine in Patients with Multidrug-/Extensively Drug-Resistant Tuberculosis

BACKGROUND AND OBJECTIVE

Multidrug-resistant tuberculosis has much poorer treatment outcomes compared with drug-susceptible tuberculosis because second-line drugs for treating multidrug resistant tuberculosis are less effective and are frequently associated with side effects. Optimization of drug treatment is urgently needed. Cycloserine is a second-line tuberculosis drug with variable pharmacokinetics and thus variable exposure when programmatic doses are used. The objective of this study was to develop a population pharmacokinetic model of cycloserine to assess drug exposure and to develop a limited sampling strategy for cycloserine exposure monitoring.

MATERIAL AND METHODS

Patients with multidrug-/extensively drug-resistant tuberculosis who were treated for > 7 days with cycloserine were eligible for inclusion. Patients received cycloserine 500 mg (body weight ≤ 50 kg) or 750 mg (body weight > 50 kg) once daily. MW/Pharm 3.83 (Mediware, Groningen, The Netherlands) was used to parameterize the population pharmacokinetic model. The model was compared with pharmacokinetic values from the literature and evaluated with a bootstrap analysis, Monte Carlo simulation, and an external dataset. Monte Carlo simulations were used to develop a limited sampling strategy.

RESULTS

Cycloserine plasma concentration vs time curves were obtained from 15 hospitalized patients (nine male, six female, median age 35 years). Mean dose/kg body weight was 11.5 mg/kg (standard deviation 2.04 mg/kg). Median area under the concentration-time curve over 24 h (AUC_0-24 h) of cycloserine was 888 h mg/L (interquartile range 728-1252 h mg/L) and median maximum concentration of cycloserine was 23.31 mg/L (interquartile range 20.14-33.30 mg/L). The final population pharmacokinetic model consisted of the following pharmacokinetic parameters [mean (standard deviation)]: absorption constant K_{a_po} of 0.39 (0.31) h^-1, distribution over the central compartment (V_d) of 0.54 (0.26) L/kg LBM, renal clearance as fraction of the estimated glomerular filtration rate of 0.092 (0.038), and metabolic clearance of 1.05 (0.75) L/h. The population pharmacokinetic model was successfully evaluated with a bootstrap analysis, Monte Carlo simulation, and an external dataset of Chinese patients (difference of 14.6% and 19.5% in measured and calculated concentrations and AUC_0-24 h, respectively). Root-mean-squared-errors found in predicting the AUC_0-24 h using a one- (4 h) and a two- (2 h and 7 h) limited sampling strategy were 1.60% and 0.14%, respectively.

CONCLUSIONS

This developed population pharmacokinetic model can be used to calculate cycloserine concentrations and exposure in patients with multidrug-/extensively drug-resistant tuberculosis. This model was successfully validated by internal and external validation methods. This study showed that the AUC_0-24 h of cycloserine can be estimated in patients with multidrug-/extensively drug-resistant tuberculosis using a 1- or 2-point limited sampling strategy in combination with the developed population pharmacokinetic model. This strategy can be used in studies to correlate drug exposure with clinical outcome. This study also showed that good target attainment rates, expressed by time above the minimal inhibitory concentration, were obtained for cycloserine with a minimal inhibitory concentration of 5 and 10 mg/L, but low rates with a minimal inhibitory concentration of 20 and 32.5 mg/L.

Pharmacokinetic, Pharmacodynamic, and Safety Profiles of Ferric Carboxymaltose in Chinese Patients with Iron-deficiency Anemia

PURPOSE

Iron deficiency (ID) is one of the most commonly known nutritional deficiencies and is considered the primary cause of anemia (iron-deficiency anemia). Ferric carboxymaltose (FCM), an intravenous iron preparation, has been widely used for >10 years for iron-deficiency anemia treatment worldwide because of its many advantages.

METHODS

This single-center, open-label, single dose escalation study in Chinese subjects was designed to assess the pharmacokinetic/pharmacodynamic parameters and safety of FCM in this population. The first 12 subjects received a 500-mg dose; after assessing safety data from the first 6 subjects in this cohort, another 12 subjects were assigned to the 1000-mg dose cohort.

FINDINGS

After an infusion of FCM over 15 min, a rapid dose-dependent increase in total serum iron levels was observed with a median T_max of 30 min following the start of the infusion for both cohorts. The C_max and AUC for the 1000-mg dose were ~1.8-fold (p = 0.2929) and 2.3-fold (p = 0.0318) those associated with the 500-mg dose, respectively. Mean terminal t_1/2 values were 12.3 and 10.5 h for the 2 cohorts. The renal elimination of FCM was negligible (<0.1%). Increase in mean serum iron levels and ferritin concentrations showed dose dependency. Iron-binding capacity was transiently well utilized after dosing, as indicated by transferrin saturation >88% with 500-mg FCM and >90% with 1000-mg FCM. Hemoglobin levels did not show significant changes during the 7-day observation period, whereas mean reticulocyte counts significantly increased in both cohorts, suggesting activation of the hematopoietic system. FCM was well tolerated in these Chinese subjects. No new or unexpected treatment-emergent adverse events were attributable to FCM.

IMPLICATIONS

The pharmacokinetic/pharmacodynamic and safety profiles in Chinese subjects seemed comparable to those in white and Japanese populations. ChinaDrugTrials.org.cn identifier: CTR20160863.