A review and assessment of potential sources of ethnic differences in drug responsiveness

Pharmacokinetics, Pharmacodynamics, and Safety Evaluation of the Novel HIF-PH Inhibitor Enarodustat: An Open-Label Phase I Study in Healthy Chinese Participants

BACKGROUND AND OBJECTIVES

Enarodustat is a hypoxia-inducible factor-prolyl hydroxylase inhibitor. We evaluated the pharmacokinetics, pharmacodynamics, and safety profile of domestic enarodustat (SAL-0951) and analyzed the influence of ethnic factors.

METHODS

In this phase I study, healthy Chinese participants received single and multiple oral doses (1, 5, and 15 mg) of SAL-0951 while in a fasted state. We monitored the pharmacokinetics, pharmacodynamics, and safety characteristics and analyzed the impact of ethnicity on pharmacokinetic characteristics.

RESULTS

In total, 33 healthy Chinese participants were enrolled; the mean age was 31.2 ± a standard deviation of 5.5 years. After single doses of 1, 5, and 15 mg were administered under fasted conditions, SAL-0951 was rapidly absorbed. Mean maximum plasma concentration and area under the plasma concentration-time curve from time 0 to the last quantifiable concentration increased dose proportionately from 0.14 to 2.54 μg/mL and from 0.63 to 9.50 h × μg/mL, respectively. The elimination half-life was 6.13, 6.32, and 6.74 h, respectively, in these three groups, and the mean value of apparent clearance ranged from 1.64 to 1.89 L/h. SAL-0951 was excreted mostly as the parent compound. It reached a stable concentration after 5 days of multiple-dose administration. We observed no drug accumulation or time-dependent pharmacokinetic characteristics and no significant difference in pharmacokinetic characteristics between Chinese and Japanese participants.

CONCLUSION

SAL-0951 was safe and well tolerated in healthy Chinese participants and had a linear pharmacokinetic profile. We found no ethnic differences in the pharmacokinetic characteristics of the drug between Chinese and Japanese populations.

CLINICAL TRIAL REGISTRATION

Registered at Chinadrugtrials.org.cn, registration number CTR2020245.

Population pharmacokinetics of levetiracetam in Chinese adult epilepsy patients with varying renal function: exposure simulation and individualized dosing adjustments

Levetiracetam (LEV) has become a first-line treatment option for various types of epilepsy with a broad spectrum of efficacy and favorable pharmacokinetic profile. We aimed to develop a population pharmacokinetic (PPK) model for LEV and devise a model-based dosing guideline specific to Chinese adult epilepsy patients. Employing Phoenix NLME 7.0 software, we utilized the first-order conditional estimation and extended least squares method to establish the PPK model. The PK of LEV was effectively characterized using a one-compartment model. Monte Carlo simulations were then performed to generate dosing guidelines suitable for various patient groups. The Bayesian feedback method was employed to develop the clinical individual predictive model. Data from 80 Chinese adult patients yielded 148 LEV plasma concentrations for analysis. In the final model, the absorption rate constant was fixed at 2.44. The apparent volume of distribution and the apparent clearance (CL/F) had population typical values of 35.34 L and 3.24 L/h, respectively. CL/F of LEV was significantly influenced by creatinine clearance (CrCL), identified as a major covariate. Monte Carlo simulations indicated that regimens of 0.5 g, 0.75 g, 1.0 g, 1.5 g, 2.0 g, 2.5 g, and 3.5 g twice daily were associated with the highest probability of target attainment (PTA) in patients with different renal function levels. Accordingly, a user-friendly dose recommendation was formulated for these patients. The individual predictive model accurately matched the observed concentrations and managed to guide the personalized dose adjustment. The PPK model linked CL/F to CrCL. Model-based simulations suggest that higher dosage adjustments may be necessary for those with augmented renal function. The developed clinical individual predictive model could effectively guide personalized dose adjustments, potentially reducing the need for frequent drug concentration measurements.

The global status of bioequivalence trials: a comprehensive clinical trial landscape analysis based on the Trialtrove database

This study presents a comprehensive analysis of the global bioequivalence (BE) trial landscape over the past 21 years, utilizing data from the Trialtrove database. We analyzed 12,450 BE trials conducted from 2003 to 2023, revealing a significant upward trend in trial numbers. Among the analysis, the primary therapeutic areas identified were cardiovascular diseases (23.17%) and metabolic/endocrinology conditions (18.91%). China leads in BE trials, accounting for 57.20% of the total, followed by Russia and the United States. Most trials are sponsored by the industry, predominantly by generic pharmaceutical companies. This study highlights the importance of diverse representation in trial populations to enhance the validity of results. We discuss strategies for improving trial success rates, including preliminary trials and in vitro dissolution testing. Furthermore, the need for international harmonization of generic drug standards is emphasized, along with the potential impact of advanced technologies, such as artificial intelligence, on future BE research.

Globalization of clinical research in oncology: Status, challenges, and future directions

PURPOSE

Cancer is the second-leading cause of death worldwide, and its burden is increasing around the world, particularly in low- and middle-income countries (LMICs). Yet, cancer research has historically been conducted primarily in high-income countries (HICs).

METHODS

In this review, we describe the results of our literature search into the current state of international cancer trials, including the benefits, challenges, limitations, and ethical concerns regarding the international conduct of HIC-led trials. We also propose some possible means of addressing these challenges and overcoming these barriers to extend the benefits of cancer research to people around the world.

RESULTS

Over the last several decades, there has been a shift toward inclusion of investigators and participants from LMICs in pivotal cancer clinical trials.

CONCLUSIONS

While inclusion of LMIC countries has benefits, including increased diversity of participant populations, investment in research infrastructure in LMICs, and potential expansion of cancer treatment options around the world, the continued leadership of most trials by HICs presents ethical concerns, including potential exploitation of researchers and participants from LMICs, lack of focus on cancer types prevalent in all participating regions, and disparities in access to approved therapies once the trial is complete.

Assessing the ability of the Cancer and Aging Research Group tool to predict chemotherapy toxicity in older Japanese patients: A prospective observational study

INTRODUCTION

The Cancer and Aging Research Group (CARG) prediction tool was designed in the United States to predict grade ≥ 3 chemotherapy-related adverse events (CRAE) in older patients. However, its usefulness among Japanese people, who have different sensitivities to anticancer drugs and life expectancy, remains unknown. We aimed to prospectively evaluate the utility of the CARG tool for predicting severe CRAE in older Japanese patients with cancer.

MATERIAL AND METHODS

Patients with solid tumors aged 65 years and older who commenced anticancer drug regimens from April 2018 to October 2020 were divided into three groups (low, medium, and high-risk) based on their CARG risk scores. Toxicity was prospectively observed by a pharmacist. The primary objective was to evaluate the correlation between the incidence of grade ≥ 3 CRAE and the CARG risk score. The secondary objective was to evaluate hematological and non-hematological toxicities. CRAE incidence was compared among the three groups using a closed testing procedure: (1) Cochran-Armitage test for trend and (2) chi-square test for paired comparison.

RESULTS

The patients (N = 165) had a median age of 71 years (range: 65-89 years). CRAE in patients divided into low-, medium-, and high-risk groups, based on CARG risk scores, were 39%, 55%, and 82%, respectively (low vs high; p < 0.001, medium vs high; p < 0.01). The incidence of severe hematologic toxicity was 37%, 35%, and 50% in the low-, medium-, and high-risk groups, respectively; the incidence of severe non-hematologic toxicity was 15%, 36%, and 65%, respectively (low vs medium; p < 0.01, low vs high; p < 0.001, and medium vs high; p < 0.01).

DISCUSSION

To our knowledge, this is the first prospective observational study to validate the CARG prediction tool in older Japanese patients with cancer. The CARG risk score may be effective in predicting the development of non-hematologic toxicities. These results should be considered when administering chemotherapy to older Japanese patients with advanced solid tumors.

Pharmacokinetics and Safety of the Tyrosine Kinase 2 Inhibitor Deucravacitinib in Healthy Chinese Subjects

INTRODUCTION

Deucravacitinib, an oral, selective, allosteric tyrosine kinase 2 inhibitor, blocks cytokine signaling involved in psoriasis pathogenesis. This ethnic-bridging study evaluated deucravacitinib pharmacokinetics, tolerability, and safety in healthy Chinese subjects.

METHODS

This phase I, double-blind, single-/multiple-dose study randomized healthy Chinese subjects 4:1 to a single dose of deucravacitinib 6 mg or placebo (group 1) or deucravacitinib 12 mg or placebo (group 2) on day 1; groups 1 and 2 received deucravacitinib 6 mg and 12 mg once daily, respectively, or placebo on days 5-19. Blood samples were collected on days 1-5 (0 predose-96 h postdose), day 5 (0-24 h postdose), days 9 and 12 (0 h), and day 19 (0-24 h postdose). Deucravacitinib and metabolite (BMT-153261, BMT-158170) concentrations were determined using liquid chromatography/mass spectrometry; pharmacokinetic parameters were calculated using noncompartmental analysis. Urine was collected on days 1-4 (4 h predose-96 h postdose). Safety was monitored throughout.

RESULTS

Forty healthy Chinese subjects (groups 1 and 2: deucravacitinib, n = 32; placebo, n = 8) were enrolled. Deucravacitinib was rapidly absorbed after single-/multiple-dose administration, with median time to maximal plasma concentration of 1.5-2.3 h. Systemic exposure after single or multiple doses increased approximately twofold with twofold dose increase. Modest deucravacitinib accumulation was observed after multiple-dose administration (1.3- to 1.4-fold increase in area under the curve [AUC] under one dosing interval). Metabolite-to-parent ratios for maximal plasma concentration and AUC remained consistent in each dose group. Mean urinary percent recovery and renal clearance were similar between dose groups. Most adverse events (AEs) were mild/moderate, with no serious treatment-related AEs, deaths, or discontinuations due to AEs.

CONCLUSION

Deucravacitinib was safe and well tolerated in healthy Chinese subjects. Deucravacitinib exhibited rapid absorption, dose-related increases in exposure, comparable half-life, and no evidence of time-dependent pharmacokinetics, suggesting minimal effect of Chinese ethnicity on deucravacitinib pharmacokinetics.

CLINICAL TRIAL REGISTRATION

NCT03956953.

A Phase 1 Study of Ensitrelvir Fumaric Acid Tablets Evaluating the Safety, Pharmacokinetics and Food Effect in Healthy Adult Populations

BACKGROUND

A reported clinical pharmacokinetics and safety study of suspension formulation of ensitrelvir, a therapeutic agent used in severe acute respiratory syndrome coronavirus 2 infection, demonstrated favorable pharmacokinetics and was well tolerated in healthy male Japanese and White participants. Understanding the safety and pharmacokinetic features of ensitrelvir (using the formulation approved for clinical use) in various populations, and the effect of food, is crucial for optimal clinical use.

OBJECTIVES

The objectives of this study were to (1) assess the safety, tolerability, and pharmacokinetics of ensitrelvir following multiple-dose administration of ensitrelvir tablets in populations with different races, ages, and sex; and (2) assess the effect of food on the pharmacokinetics of ensitrelvir tablets in the fasted or fed state.

METHODS

A phase 1, multicenter, double-blinded, randomized, placebo-controlled study was conducted to evaluate the safety and pharmacokinetics of once-daily ensitrelvir tablets at loading/maintenance doses of 375/125 mg or 750/250 mg for 5 days in healthy Japanese females, Japanese elderly (only 375/125 mg), and White male and female participants. An open-label, two-group, two-period crossover study was also conducted to estimate the effect of food on the pharmacokinetics of ensitrelvir at single dose of 375 mg. The nature, frequency, and severity of treatment-emergent adverse events were evaluated and recorded in safety assessments in both studies.

RESULTS

The maximum plasma concentration (Cmax) and area under the plasma concentration-time curve (AUC) were similar within these populations. The geometric mean half-life of ensitrelvir following multiple-dose administration was 48.7-58.9 h across all cohorts. The Cmax and AUC increased in a dose-proportional manner in Japanese female participants, and increased in a less than dose-proportional manner in White participants. Furthermore, there was no clear relationship between the dose and geometric mean half-life of ensitrelvir. The plasma concentration at 24 h (C24) after an initial dose of 375/125 mg exceeded the target plasma concentration (6.09 µg/mL) in all populations. Regarding the effect of food on the pharmacokinetics of ensitrelvir, although time to Cmax in the fed state was delayed, there was no clinically meaningful difference in the exposure levels (Cmax and AUC) of ensitrelvir between the fasted and fed states. Most treatment-emergent adverse events were mild in nature and had resolved.

CONCLUSION

Ensitrelvir (375/125 mg and 750/250 mg tablet formulation) was well tolerated, without any major safety concerns. The pharmacokinetics of ensitrelvir between all populations in the study were similar and C24 exceeded the target plasma concentration at 375/125 mg. These results suggest that ensitrelvir can be effectively administered with no necessity for dose adjustment for age, sex, and race without food restriction.

CLINICAL TRIAL REGISTRATION

Japan Registry of Clinical Trials identifier: jRCT2031210202, registered on 16 July 2021.

Race, Ethnicity, and Pharmacogenomic Variation in the United States and the United Kingdom

The relevance of race and ethnicity to genetics and medicine has long been a matter of debate. An emerging consensus holds that race and ethnicity are social constructs and thus poor proxies for genetic diversity. The goal of this study was to evaluate the relationship between race, ethnicity, and clinically relevant pharmacogenomic variation in cosmopolitan populations. We studied racially and ethnically diverse cohorts of 65,120 participants from the United States All of Us Research Program (All of Us) and 31,396 participants from the United Kingdom Biobank (UKB). Genome-wide patterns of pharmacogenomic variation-6311 drug response-associated variants for All of Us and 5966 variants for UKB-were analyzed with machine learning classifiers to predict participants' self-identified race and ethnicity. Pharmacogenomic variation predicts race/ethnicity with averages of 92.1% accuracy for All of Us and 94.3% accuracy for UKB. Group-specific prediction accuracies range from 99.0% for the White group in UKB to 92.9% for the Hispanic group in All of Us. Prediction accuracies are substantially lower for individuals who identified with more than one group in All of Us (16.7%) or as Mixed in UKB (70.7%). There are numerous individual pharmacogenomic variants with large allele frequency differences between race/ethnicity groups in both cohorts. Frequency differences for toxicity-associated variants predict hundreds of adverse drug reactions per 1000 treated participants for minority groups in All of Us. Our results indicate that race and ethnicity can be used to stratify pharmacogenomic risk in the US and UK populations and should not be discounted when making treatment decisions. We resolve the contradiction between the results reported here and the orthodoxy of race and ethnicity as non-genetic, social constructs by emphasizing the distinction between global and local patterns of human genetic diversity, and we stress the current and future limitations of race and ethnicity as proxies for pharmacogenomic variation.

Race and Ethnicity in Lewy Body Dementia: A Narrative Review

Lewy body dementia is the third most common and costliest type of dementia. It is an umbrella term for dementia with Lewy bodies and Parkinson's disease dementia, both of which place a substantial burden on the person and society. Recent findings outline ethnoracial differences in dementia risk. Delayed and misdiagnosis across ethnoracial groups contribute to higher levels of burden. In this context, we aimed to summarize current knowledge, gaps, and unmet needs relating to race and ethnicity in Lewy body dementia. In this narrative review, we provide an overview of studies on Lewy body dementia focusing on differences across ethnoracial groups and outline several recommendations for future studies. The majority of the findings comparing different ethnoracial groups were from North American sites. There were no differences in clinical prevalence and progression across ethnoracial groups. Compared to people identifying as non-Hispanic White, co-pathologies were more common and clinical diagnostic accuracy was lower for people identifying as Black. Co-morbidities (e.g., diabetes, hypertension) were more common and medication use rates (e.g., antidepressants, antiparkinsonian agents) were lower for people identifying as Black or Hispanic compared to people identifying as White. More than 90% of clinical trial participants identified as non-Hispanic White. Despite increasing efforts to overcome disparities in Alzheimer's disease and related dementias, inclusion of individuals from minoritized communities in Lewy body dementia studies continues to be limited and the findings are inconclusive. Representation of diverse populations is crucial to improve the diagnostic and therapeutic efforts in Lewy body dementia.

Pharmacokinetic, Safety, and Tolerability Evaluations of Gepotidacin (GSK2140944) in Healthy Japanese Participants

Gepotidacin is a novel, bactericidal, first-in-class triazaacenaphthylene antibiotic in late-phase development for uncomplicated urinary tract infection and uncomplicated urogenital gonorrhea. Two clinical studies were conducted to assess the pharmacokinetics (PK) and interethnic comparisons of oral gepotidacin (free-base and to-be-marketed mesylate formulations) administered as single doses ranging from 1500 to 3000 mg in fed and fasted states, and as 2 × 3000-mg doses given 12 hours apart under fed conditions in healthy participants of Japanese ancestry. Dose proportionality was observed in plasma exposures, and comparable area under the concentration-time curve (AUC) and maximum concentration were observed in fed and fasted states. Interethnic comparisons for Japanese versus non-Japanese participant data showed slightly higher plasma maximum concentration (7%-30%) yet similar plasma AUCs; slightly lower urine AUCs (11%-18%) were observed. The slightly higher plasma exposures in healthy Japanese versus White participants in the same study were attributed to lower mean body weights (64 kg versus ≈80 kg). Adverse events were primarily gastrointestinal, and when administered with food, gastrointestinal tolerability was improved. Overall, the gepotidacin PK and safety-risk profiles in healthy Japanese support potential evaluation of the global clinical doses in future studies.

Diversity in Alzheimer's disease drug trials: The importance of eligibility criteria

INTRODUCTION

To generalize safety and efficacy findings, it is essential that diverse populations are well represented in Alzheimer's disease (AD) drug trials. In this review, we aimed to investigate participant diversity in disease-modifying AD trials over time, and the frequencies of participant eligibility criteria.

METHODS

A systematic review was performed using Medline, Embase, the Cochrane Library, and Clinicaltrials.gov, identifying 2247 records.

RESULTS

In the 101 included AD trials, participants were predominantly White (median percentage: 94.7%, interquartile range: 81.0-96.7%); and this percentage showed no significant increase or decrease over time (2001-2019). Eligibility criteria such as exclusion of persons with psychiatric illness (78.2%), cardiovascular disease (71.3%) and cerebrovascular disease (68.3%), obligated caregiver attendance (80.2%), and specific Mini-Mental State Examination scores (90.1%; no significant increase/decrease over time) may have led to a disproportionate exclusion of ethnoracially diverse individuals.

DISCUSSION

Ethnoracially diverse participants continue to be underrepresented in AD clinical trials. Several recommendations are provided to broaden eligibility criteria.

Genotypic and phenotypic landscapes of 51 pharmacogenes derived from whole-genome sequencing in a Thai population

Differences in drug responses in individuals are partly due to genetic variations in pharmacogenes, which differ among populations. Here, genome sequencing of 171 unrelated Thai individuals from all regions of Thailand was used to call star alleles of 51 pharmacogenes by Stargazer, determine allele and genotype frequencies, predict phenotype and compare high-impact variant frequencies between Thai and other populations. Three control genes, EGFR, VDR, and RYR1, were used, giving consistent results. Every individual had at least three genes with variant or altered phenotype. Forty of the 51 pharmacogenes had at least one individual with variant or altered phenotype. Moreover, thirteen genes had at least 25% of individuals with variant or altered phenotype including SLCO1B3 (97.08%), CYP3A5 (88.3%), CYP2C19 (60.82%), CYP2A6 (60.2%), SULT1A1 (56.14%), G6PD (54.39%), CYP4B1 (50.00%), CYP2D6 (48.65%), CYP2F1 (46.41%), NAT2 (40.35%), SLCO2B1 (28.95%), UGT1A1 (28.07%), and SLCO1B1 (26.79%). Allele frequencies of high impact variants from our samples were most similar to East Asian. Remarkably, we identified twenty predicted high impact variants which have not previously been reported. Our results provide information that contributes to the implementation of pharmacogenetic testing in Thailand and other Southeast Asian countries, bringing a step closer to personalized medicine.

Genetic Ancestry Inference for Pharmacogenomics

Genetic ancestry inference can be used to stratify patient cohorts and to model pharmacogenomic variation within and between populations. We provide a detailed guide to genetic ancestry inference using genome-wide genetic variant datasets, with an emphasis on two widely used techniques: principal components analysis (PCA) and ADMIXTURE analysis. PCA can be used for patient stratification and categorical ancestry inference, whereas ADMIXTURE is used to characterize genetic ancestry as a continuous variable. Visualization methods are critical for the interpretation of genetic ancestry inference methods, and we provide instructions for how the results of PCA and ADMIXTURE can be effectively visualized.

Using increased trust in medical researchers to increase minority recruitment: The RECRUIT cluster randomized clinical trial

While extensive literature exists on barriers and strategies to increase minority participation in clinical trials, progress is limited. Few strategies were evaluated in randomized trials. We studied the impact of RECRUIT, a trust-based, cluster randomized minority recruitment trial layered on top of four traditional NIH-funded parent trials (BMT CTN, CABANA, PACES, STEADY-PD III; fifty specialty sites). RECRUIT was conducted from July 2013 through April 2017. Intervention sites implemented trust-based approaches customized to individual sites, promoting relationships between physician-investigators and minority-serving physicians and their minority patients. Control sites implemented only parent trials' recruitment procedures. Adjusting for within-site clustering, we detected no overall intervention effect, odds ratio 1.3 (95% confidence limits 0.7,2.4). Heterogeneity among parent trials may have obscured the effect. Of the four parent trials, three enrolled more minorities in intervention versus control sites. CABANA odds ratio = 4.2 (adjusted 95%CL 1.5,11.3). PACES intervention sites enrolled 63% (10/16) minorities; control sites enrolled one participant in total, a minority, yielding an incalculable odds ratio. STEADY-PD III odds ratio = 2.2 (adjusted 95%CL 0.6,8.5). BMT CTN odds ratio < 1, 0.8 (adjusted 95%CL 0.4,1.8). In conclusion, RECRUIT findings suggest the unique trust-based intervention increased minority recruitment to intervention trials in ¾ of studied trials. Physician-investigators' participation was critical to recruitment success. Lack of commitment to minority recruitment remained a barrier for some physician-investigators, especially in control sites. We recommend prospective physician investigators commit to minority recruitment activities prior to selection as site investigators and trial funding include some compensation for minority recruitment efforts. TRIAL REGISTRATION ClinicalTrials.govNCT01911208.

Population pharmacokinetic and exposure-response analysis of apremilast in Japanese subjects with moderate to severe psoriasis

Apremilast is an orally available phosphodiesterase 4 inhibitor used for the treatment of moderate to severe psoriasis. The aims of this analysis were to develop a population pharmacokinetic (PPK) model of apremilast based on observed data from phase 1 studies combined with clinical trial data from subjects with moderate to severe psoriasis, and to develop exposure–response (E‐R) models to determine whether Japanese subjects with moderate to severe psoriasis achieve response to apremilast treatment similar to that observed in non‐Japanese, predominantly Caucasian subjects with moderate to severe psoriasis. The PPK model demonstrated that apremilast plasma concentrations and overall apparent clearance rate were comparable between the Japanese and Caucasian subgroups. The E‐R analyses of ≥75% or ≥50% improvement from baseline in Psoriasis Area and Severity Index score and achievement of static Physician Global Assessment score of 0 (clear) or 1 (almost clear) at week 16 indicated that apremilast treatment in Japanese subjects approached the maximal effect with response rates comparable to those in predominantly Caucasian subjects. Overall, the analyses confirm that the approved apremilast 30 mg b.i.d. dose is appropriate for Japanese subjects with moderate to severe psoriasis, with an efficacy profile similar to that previously observed in Caucasian subjects.

Modifiable Barriers for Recruitment and Retention of Older Adults Participants from Underrepresented Minorities in Alzheimer's Disease Research

Clinical Alzheimer's disease (AD) trials currently face a critical shortfall of thousands of eligible participants, which inflates the duration and cost of the clinical study as well as threatens the scientific merit of promising clinical interventions. This recruitment crisis is further compounded by the fact that underrepresented and marginalized populations-particularly those identifying as a racial or ethnic minority, those with low socioeconomic status, or living in rural areas-have been historically underrepresented in ongoing AD clinical trials despite overwhelming evidence that such populations are at increased risk for developing dementia. As a result of various recruitment barriers, current AD clinical studies frequently reflect a decreasingly representative segment of the US population, which threatens the overall generalizability of these findings. The current narrative review provides an updated examination and critique of common recruitment barriers and potential solutions, as well as a discussion of theoretical approaches that may address barriers disproportionately experienced by underrepresented communities. AD clinical researchers are encouraged to take purposive action aimed at increasing diversity of enrolled AD clinical trial cohorts by actively identifying and quantifying barriers to research participation-especially recruitment barriers and health disparities that disproportionately prevent underrepresented and marginalized populations from participating in research. Furthermore, researchers are encouraged to closely track which individuals who express interest in AD research ultimately enroll in research studies to examine whether AD research participation is appropriately representative of the intended population for whom these new and novel AD interventions are being designed.

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.

Population structure and pharmacogenomic risk stratification in the United States

BACKGROUND

Pharmacogenomic (PGx) variants mediate how individuals respond to medication, and response differences among racial/ethnic groups have been attributed to patterns of PGx diversity. We hypothesized that genetic ancestry (GA) would provide higher resolution for stratifying PGx risk, since it serves as a more reliable surrogate for genetic diversity than self-identified race/ethnicity (SIRE), which includes a substantial social component. We analyzed a cohort of 8628 individuals from the United States (US), for whom we had both SIRE information and whole genome genotypes, with a focus on the three largest SIRE groups in the US: White, Black (African-American), and Hispanic (Latino). Our approach to the question of PGx risk stratification entailed the integration of two distinct methodologies: population genetics and evidence-based medicine. This integrated approach allowed us to consider the clinical implications for the observed patterns of PGx variation found within and between population groups.

RESULTS

Whole genome genotypes were used to characterize individuals' continental ancestry fractions-European, African, and Native American-and individuals were grouped according to their GA profiles. SIRE and GA groups were found to be highly concordant. Continental ancestry predicts individuals' SIRE with > 96% accuracy, and accordingly, GA provides only a marginal increase in resolution for PGx risk stratification. In light of the concordance between SIRE and GA, taken together with the fact that information on SIRE is readily available to clinicians, we evaluated PGx variation between SIRE groups to explore the potential clinical utility of race and ethnicity. PGx variants are highly diverged compared to the genomic background; 82 variants show significant frequency differences among SIRE groups, and genome-wide patterns of PGx variation are almost entirely concordant with SIRE. The vast majority of PGx variation is found within rather than between groups, a well-established fact for almost all genetic variants, which is often taken to argue against the clinical utility of population stratification. Nevertheless, analysis of highly differentiated PGx variants illustrates how SIRE partitions PGx variation based on groups' characteristic ancestry patterns. These cases underscore the extent to which SIRE carries clinically valuable information for stratifying PGx risk among populations, albeit with less utility for predicting individual-level PGx alleles (genotypes), supporting the concept of population pharmacogenomics.

CONCLUSIONS

Perhaps most interestingly, we show that individuals who identify as Black or Hispanic stand to gain far more from the consideration of race/ethnicity in treatment decisions than individuals from the majority White population.

Pharmacokinetics, Safety, and Tolerability of Single- and Multiple-Dose Once-Daily Baricitinib in Healthy Chinese Subjects: A Randomized Placebo-Controlled Study

The objective of this phase 1 study was to evaluate the pharmacokinetics, safety, and tolerability of baricitinib after single and multiple doses in healthy Chinese adults. Eligible subjects received a once‐daily dose of baricitinib 2, 4, or 10 mg or placebo on day 1 (single dose) and days 4 through 10 for 7 consecutive days (multiple doses). Plasma pharmacokinetic samples were collected up to 48 hours after dosing on days 1 and 10, with predose samples collected before dosing on day 1 and days 4 through 10. Safety and tolerability were also assessed. Baricitinib was rapidly absorbed, reaching peak plasma concentrations within 0.5 to 1 hour (median). Plasma concentrations declined rapidly following the attainment of peak concentrations, with a mean terminal half‐life of 5.7 to 7.3 hours. Steady‐state plasma concentrations of baricitinib were achieved after the second day of once‐daily dosing, with minimal accumulation of baricitinib in plasma (up to 10% increase in area under the plasma concentration–time curve). Single‐ and multiple‐dose mean values for area under the plasma concentration–time curve from time zero to infinity and maximum plasma concentration appeared to increase in an approximately dose‐proportional manner across the dose range. Single and multiple oral doses of once‐daily baricitinib up to 10 mg were well tolerated by healthy Chinese subjects.

Pharmacokinetics and Pharmacodynamics of Two Formulations of Pegylated Recombinant Human Granulocyte Colony-Stimulating Factor in Healthy Chinese Subjects: An Open-Label, Randomized, Parallel-Design Bioavailability Study

Pegylated recombinant human granulocyte colony-stimulating factor (PEG-rhG-CSF, pegfilgrastim) is a long-acting derivative of recombinant human granulocyte colony-stimulating factor with limited renal clearance and a longer half-life. It is used for the prevention of febrile neutropenia, owing to its capacity to promote neutrophil recovery. In this study, the pharmacokinetics, pharmacodynamics, safety, and immunogenicity of 2 formulations of PEG-rhG-CSF were evaluated in healthy Chinese subjects. Twenty-four male subjects who received a single dose of subcutaneous PEG-rhG-CSF 100 µg/kg were randomized to either treatment A (3 mg/mL) or treatment B (1 mg/mL). Noncompartmental pharmacokinetic parameters of PEG-rhG-CSF were derived from serum concentration-time data. In addition, absolute neutrophil count (ANC) as a pharmacodynamic maker, immunogenicity through antidrug antibody testing, and safety were evaluated. The mean area under the concentration-time curve from time zero to the last quantifiable concentration (AUC_0-t ) and the mean maximum concentration (C_max ) of PEG-rhG-CSF after treatment A were 5070 ng·h/mL and 125 ng/mL, respectively; these values were comparable to those measured after treatment B (5340 ng·h/mL and 123 ng/mL, respectively). The mean value of area under the △ANC (baseline-adjusted ANC)-time curve and the maximum △ANC values were 4380 × 10⁹  h/L and 33.1 × 10⁹ /L, respectively, in the treatment A group, and 5170 × 10⁹  h/L and 38.6 × 10⁹ /L, respectively, in the treatment B group. The pharmacokinetic and pharmacodynamic profiles were similar for the 2 PEG-rhG-CSF formulations following a single dose of 100 µg/kg. The safety and immunogenicity profiles were also similar, with no significant differences. The dose adjustment of PEG-rhG-CSF was not considered necessary for formulation transformation.

Pharmacokinetics of Oral Levonorgestrel in Women After Roux-en-Y Gastric Bypass Surgery and in BMI-Matched Controls

BACKGROUND

Women are advised to primarily use non-oral contraceptive alternatives after Roux-en-Y gastric bypass since it is not known if the surgery affects the pharmacokinetics of oral contraceptives.

METHODS

This is a multi-center, open label, phase 2 pharmacokinetic study performed at the University Hospital of Linköping and the Clinical Trials Center, Department of Obstetrics and Gynecology, Danderyd Hospital, Karolinska Institutet, Stockholm, Sweden. Fifteen women aged 18-40 years who had previously undergone Roux-en-Y gastric bypass surgery and reached a BMI < 30 were included. Fifteen BMI-matched women with no previous history of Roux-en-Y gastric bypass surgery served as a control group. After administration of a single dose of a combined oral contraceptive containing 0.03 mg ethinylestradiol/0.15 mg levonorgestrel, serum levonorgestrel concentrations were determined during a 24-h period using ultra performance liquid chromatography/tandem mass spectrometry. The area under the plasma concentration time curve of levonorgestrel (AUC0-24h) was the main outcome measure.

RESULTS

There were no significant differences in the studied pharmacokinetic parameters, AUC0-24h, total AUC, peak serum concentration (Cmax), time to peak serum concentrations (Tmax), apparent oral clearances of levonorgestrel (CLoral), or terminal half-lives (t½) between the groups.

CONCLUSION

This is to our knowledge the first study to evaluate the pharmacokinetics of oral levonorgestrel in women with a BMI < 30 at least 1 year after RYGB compared with a BMI-matched group of women. We could not find any significant pharmacokinetic differences between the groups, suggesting that oral levonorgestrel may be used in non-obese women after Roux-en-Y gastric bypass once a stable body weight has been reached.

CLINICAL TRIAL NUMBER

EudraCT 2014-004677-17.

The Effects of Cruciferous Vegetable-Enriched Diets on Drug Metabolism: A Systematic Review and Meta-Analysis of Dietary Intervention Trials in Humans

Relatively few studies exist in the literature that discuss the effects of diet on drug metabolism and how this can affect interindividual differences in systemic drug exposure. Several studies have investigated the effects of cruciferous vegetables (Cruciferae) or their constituents on drug-metabolizing activity, as these vegetables form an important part of many peoples' diets. In general, the ingestion of cruciferous vegetables is associated with induction of cytochrome P450 (CYP) 1A2 activity in vivo; however, there is contention between reports, and the clinical significance of potential diet-drug interactions remains unclear. This study reports a systematic review, critical appraisal, and meta-analysis of the published literature in this area, and discusses the clinical significance of Cruciferae-enriched diets in the context of diet-drug interactions. Twenty-three dietary intervention trials with drug metabolism end points were identified across Embase, Medline, and the Cochrane Controlled Register of Trials (CENTRAL). Cruciferous vegetables represented in the literature included broccoli, Brussels sprout, cabbage, cauliflower, radish, and watercress. A range of phase I and II drug-metabolizing enzymes and phenotyping metrics were represented in the literature. The meta-analyses performed demonstrated a significant effect on CYP1A2 and glutathione S-transferase-alpha (GST-α), with consumption of Cruciferae increasing the activities of these enzymes by 20-40% and 15-35%, respectively. The results herein suggest that patients undergoing pharmacotherapy with CYP1A2 or GST-α substrates could have altered drug exposure profiles if they regularly eat large or variable amounts of cruciferous vegetables. Recommendations regarding the design of future randomized, controlled trials to test hypotheses in this area are included.

Pharmacokinetics of thiotepa in high-dose regimens for autologous hematopoietic stem cell transplant in Japanese patients with pediatric tumors or adult lymphoma

Purpose

Thiotepa is used in high-dose chemotherapy (HDT) before autologous hematopoietic stem cell transplantation (HSCT) to treat solid tumors and hematological malignancies. This Phase 1 study was conducted to establish the pharmacokinetics (PK) of thiotepa in a Japanese population.

Methods

HDT/HSCT was performed in pediatric patients (≥ 2 years) with solid tumors or brain tumors (thiotepa 200 mg/m²/day IV-infused over 24 h on HSCT Days − 12, − 11, − 5, and − 4 and melphalan 70 mg/m²/day IV-infused over 1 h on Days − 11, − 5, and − 4) and adult patients (≥ 16 years) with malignant lymphoma (thiotepa 200 mg/m²/day 2-h IV-infusion on HSCT Days − 4 and − 3 plus busulfan 0.8 mg/kg 2-h IV-infusion every 6 h from HSCT Days − 8 to − 5). Pharmacokinetics of thiotepa were assessed following initial dose. Safety and efficacy were also evaluated.

Results

Nine pediatric and 10 adult patients were enrolled. Mean volume of distribution (V_z) of thiotepa normalized with body surface area (BSA) was lower for pediatric patients (16.4 L/m²) compared with adult patients (26.4 L/m²) as expected due to the higher specific surface area of children. Clearance and biological half-life were similar between pediatric and adult patients. Two serious adverse events (cardiac arrest and pulmonary edema) were observed. Survival rate (Day 100 post-HSCT) was 77.8% (95% CI 36.5–93.9%) for pediatric patients and 100% for adult patients.

Conclusion

Thiotepa elimination was comparable in pediatric and adult patients with cancer. Lower V_z in pediatric compared with adult patients was expected. HDT with thiotepa prior to autologous HSCT was well tolerated.

Study registration

Japic CTI-163433.

Electronic supplementary material

The online version of this article (10.1007/s00280-019-03914-2) contains supplementary material, which is available to authorized users.

Inconsistency in race and ethnic classification in pharmacogenetics studies and its potential clinical implications

Introduction

Racial and ethnic categories are frequently used in pharmacogenetics literature to stratify patients; however, these categories can be inconsistent across different studies. To address the ongoing debate on the applicability of traditional concepts of race and ethnicity in the context of precision medicine, we aimed to review the application of current racial and ethnic categories in pharmacogenetics and its potential impact on clinical care.

Methods

One hundred and three total pharmacogenetics papers involving the CYP2C9, CYP2C19, and CYP2D6 genes were analyzed for their country of origin, racial, and ethnic categories used, and allele frequency data. Correspondence between the major continental racial categories promulgated by National Institutes of Health (NIH) and those reported by the pharmacogenetics papers was evaluated.

Results

The racial and ethnic categories used in the papers we analyzed were highly heterogeneous. In total, we found 66 different racial and ethnic categories used which fall under the NIH race category “White”, 47 different racial and ethnic categories for “Asian”, and 62 different categories for “Black”. The number of categories used varied widely based on country of origin: Japan used the highest number of different categories for “White” with 17, Malaysia used the highest number for “Asian” with 24, and the US used the highest number for “Black” with 28. Significant variation in allele frequency between different ethnic subgroups was identified within 3 major continental racial categories.

Conclusion

Our analysis showed that racial and ethnic classification is highly inconsistent across different papers as well as between different countries. Evidence-based consensus is necessary for optimal use of self-identified race as well as geographical ancestry in pharmacogenetics. Common taxonomy of geographical ancestry which reflects specifics of particular countries and is accepted by the entire scientific community can facilitate reproducible pharmacogenetic research and clinical implementation of its results.

Early Hemoconcentration Is Associated With Increased Opioid Use in Hospitalized Patients With Acute Pancreatitis

OBJECTIVES

Opioids are commonly required for abdominal pain in hospitalized patients with acute pancreatitis (AP). The factors associated with increased opioid requirements are unknown.

METHODS

The medical records of adult inpatients with AP from 2006 to 2016 were reviewed. Patients with chronic pancreatitis, psychiatric comorbidities, intubation, chronic opioid, and illicit drug use were excluded. The total quantity of opioids required during the first 7 days of hospitalization was converted to oral morphine equivalents (OME), divided by the number of days opioids were required to obtain the mean OME per day(s) of treatment (MOME). Multiple regression analysis was performed to identify factors associated with MOME.

RESULTS

A total of 267 patients were included. The mean (standard deviation) age was 46.9 (13.9) years and 56% were males. The most common etiology was alcohol (55.4%). The mean (standard deviation) MOME was 59.1 (54.5) mg. Although age (P = 0.008), black race (P = 0.004), and first episode of AP (P = 0.049) were associated with a lower MOME, early hemoconcentration (hematocrit ≥44%) (P < 0.001) was associated with an increased MOME.

CONCLUSIONS

Early hemoconcentration is associated with an increased opioid requirement in hospitalized patients with AP. The impact of fluid therapy in these patients merits prospective study.

Evaluation of the single-dose pharmacokinetics and pharmacodynamics of apixaban in healthy Japanese and Caucasian subjects

Purpose

This double-blind, placebo-controlled, intra-subject, dose-escalation study assessed single-dose safety, pharmacokinetics, and pharmacodynamics of apixaban in healthy Japanese and Caucasian subjects.

Subjects and methods

Sixteen healthy male Japanese and sixteen healthy male Caucasian subjects, matched for age, weight, and smoking status were randomized to receive four sequential single oral doses of either apixaban (2.5, 10, 25, and 50 mg) or matched placebo. Doses were separated by a ≥5-day washout. Blood samples were collected for the determination of apixaban plasma concentration, clotting times (international normalized ratio [INR], activated partial thromboplastin time, and modified prothrombin time [mPT]), and ex vivo thrombin generation (TG). Urine samples were collected for the analysis of apixaban concentration.

Results

Ascending single doses of apixaban 2.5–50 mg were safe and well tolerated by all subjects. Apixaban exposure increased the dose proportionally up to 10 mg. Apixaban reached maximum concentrations (C_max) 3–4 h postdose, with mean C_max ranging from 52.5–485.0 to 44.8–494.3 ng/mL in Japanese and Caucasian subjects. The mean half-life was ~8 and ~13 h and the renal clearance was 1.1 and 0.8 L/h in Japanese and Caucasian subjects, respectively. Pharmacodynamic assessments were similar between ethnic groups, with comparable dose-related prolongation of INR and mPT and inhibition of TG.

Conclusion

Ascending single doses of apixaban over a 20-fold dose range were safe and well tolerated in Japanese and Caucasian subjects in this study. The consistency between pharmacokinetic and pharmacodynamic measures in Japanese and Caucasian subjects indicates that apixaban may be administered as a fixed dose with no need for adjustment in Japanese patients.

Optimal dose selection accounting for patient subpopulations in a randomized Phase II trial to maximize the success probability of a subsequent Phase III trial

Phase II clinical trials are conducted to determine the optimal dose of the study drug for use in Phase III clinical trials while also balancing efficacy and safety. In conducting these trials, it may be important to consider subpopulations of patients grouped by background factors such as drug metabolism and kidney and liver function. Determining the optimal dose, as well as maximizing the effectiveness of the study drug by analyzing patient subpopulations, requires a complex decision-making process. In extreme cases, drug development has to be terminated due to inadequate efficacy or severe toxicity. Such a decision may be based on a particular subpopulation. We propose a Bayesian utility approach (BUART) to randomized Phase II clinical trials which uses a first-order bivariate normal dynamic linear model for efficacy and safety in order to determine the optimal dose and study population in a subsequent Phase III clinical trial. We carried out a simulation study under a wide range of clinical scenarios to evaluate the performance of the proposed method in comparison with a conventional method separately analyzing efficacy and safety in each patient population. The proposed method showed more favorable operating characteristics in determining the optimal population and dose.

Pharmacokinetics and pharmacodynamics in Japanese and Caucasian subjects after oral administration of dabigatran etexilate

Ethnic differences in drug disposition may potentially influence therapeutic response to dabigatran, a reversible direct thrombin inhibitor used for the prevention and/or treatment of various thromboembolic disorders. This analysis of data from 18 clinical studies in healthy volunteers and patients with non-valvular atrial fibrillation (AF) or undergoing knee or hip arthroplasty investigated whether there were any clinically relevant differences in the pharmacokinetics and pharmacodynamics of dabigatran, the active form of dabigatran etexilate, between Japanese and Caucasian subjects. In pooled data from 14 phase I trials, total exposure (i.e. area under the plasma concentration-time curve [AUC]) after administration of dabigatran 150 mg once or twice-daily was on average 20% higher in Japanese than Caucasian subjects (median [10th to 90th percentile] 1,110 [644–1,824] vs. 924 [420–1,654] ng·h/ml) although the difference between the groups was not significant. Within-trial comparisons in subjects treated with dabigatran 150 mg twice-daily showed that AUC and maximum plasma concentration differed by less than 10% between the two groups. In patients with AF, trough concentrations after administration of 150 mg twice-daily were similar in Japanese and Caucasian subjects (80.1 [34.5–193.8] vs. 71.0 [34.0–190] ng/ml). Various factors, including body weight and renal clearance, may explain these observed pharmacokinetic differences. The relationship between plasma concentration and coagulation markers was similar and indicative of no difference in the exposure-pharmacodynamic response between these two groups. In conclusion, the results of this analysis show that the pharmacokinetics and pharmacodynamics of dabigatran are similar in Japanese and Caucasian subjects and suggest that there is no need for dose adjustment of dabigatran in Japanese subjects.

Pharmacokinetics of CYP2C9, CYP2C19, and CYP2D6 substrates in healthy Chinese and European subjects

PURPOSE

The aim of this analysis is to compare the pharmacokinetics of drug substrates in healthy Chinese and European subjects of aligned CYP2C9, CYP2C19, or CYP2D6 enzyme activity, providing further insight into drivers of interethnic differences in pharmacokinetics.

METHODS

Following identification of appropriate drug substrates, a comprehensive and structured literature search was conducted to identify single-dose pharmacokinetic data in healthy Chinese or European subjects with reported CYP2C9, CYP2C19, or CYP2D6 activity (genotype or phenotype). The ratio of drug AUC in the Chinese and European subjects classified with aligned enzyme activity was calculated (ethnicity ratio (ER)).

RESULTS

For 22/25 drugs identified, the ERs calculated indicated no or only limited interethnic differences in exposure (<twofold) in Chinese and European subjects with aligned polymorphic enzyme activity. The interethnic differences observed can reflect differences across populations in additional determinants of pharmacokinetics, although the notable between study variation and change over time in methods used to assign enzyme activity may also be contributing factors. There was no association between drug substrate fraction metabolized (fm) for CYP2C9, CYP2C19, or CYP2D6 and the ERs calculated.

CONCLUSION

The spectrum of pharmacokinetic determinants for each drug substrate and their differences across ethnic groups must be considered on a case-by-case basis in addition to metabolism by CYP2C9, CYP2C19, or CYP2D6. This analysis has also highlighted the challenges which arise when comparing published datasets if consistent methods to assign polymorphic enzyme activity have not been used.

Efficacy and safety of mepolizumab in Japanese patients with severe eosinophilic asthma

BACKGROUND

The MENSA trial assessed the efficacy and safety of mepolizumab in patients with severe eosinophilic asthma. This report describes the efficacy and safety of mepolizumab in Japanese patients from MENSA.

METHODS

A post hoc analysis of the Japanese subgroup from the randomized, double-blind, placebo-controlled, double-dummy, Phase III MENSA trial (NCT01691521). Patients ≥12 years with severe eosinophilic asthma received mepolizumab 75 mg intravenously (IV), 100 mg subcutaneously (SC), or placebo, every 4 weeks for 32 weeks. The primary endpoint was the annualized rate of exacerbations. Secondary and other endpoints included annualized rate of exacerbations requiring emergency department (ED) visit/hospitalization, morning peak expiratory flow (PEF), St George's Respiratory Questionnaire (SGRQ) score and eosinophil counts. Adverse events (AEs) were monitored.

RESULTS

In the Japanese subgroup (N = 50), the rate of clinically significant exacerbations was reduced by 90% (rate ratio [RR]: 0.10; 95% confidence interval [CI]: 0.02-0.57; P = 0.010) with mepolizumab IV and 62% (RR: 0.38; 95% CI: 0.12-1.18; P = 0.094) with mepolizumab SC, versus placebo. No exacerbations requiring ED visit/hospitalization were reported with mepolizumab IV; exacerbations were reduced by 73% (RR: 0.27; 95% CI: 0.06-1.29; P = 0.102) with mepolizumab SC versus placebo. Compared with placebo, mepolizumab IV and SC numerically increased morning PEF from baseline by 40 L/min and 13 L/min, improved quality of life by greater than the minimal clinically important difference (SGRQ: 9.5 [P = 0.083] and 7.9 [P = 0.171] points) and reduced eosinophil counts. AE incidence was similar between treatments. Results were broadly consistent with the overall population.

CONCLUSIONS

Mepolizumab was efficacious and well tolerated in Japanese patients with severe eosinophilic asthma, producing similar responses to the overall MENSA population.

Design of a cluster-randomized minority recruitment trial: RECRUIT

BACKGROUND

Racial/ethnic minority groups remain underrepresented in clinical trials. Many strategies to increase minority recruitment focus on minority communities and emphasize common diseases such as hypertension. Scant literature focuses on minority recruitment to trials of less common conditions, often conducted in specialty clinics and dependent on physician referrals. We identified trust/mistrust of specialist physician investigators and institutions conducting medical research and consequent participant reluctance to participate in clinical trials as key-shared barriers across racial/ethnic groups. We developed a trust-based continuous quality improvement intervention to build trust between specialist physician investigators and community minority-serving physicians and ultimately potential trial participants. To avoid the inherent biases of non-randomized studies, we evaluated the intervention in the national Randomized Recruitment Intervention Trial (RECRUIT). This report presents the design of RECRUIT. Specialty clinic follow-up continues through April 2017.

METHODS

We hypothesized that specialist physician investigators and coordinators trained in the trust-based continuous quality improvement intervention would enroll a greater proportion of minority participants in their specialty clinics than specialist physician investigators in control specialty clinics. Specialty clinic was the unit of randomization. Using continuous quality improvement, the specialist physician investigators and coordinators tailored recruitment approaches to their specialty clinic characteristics and populations. Primary analyses were adjusted for clustering by specialty clinic within parent trial and matching covariates.

RESULTS

RECRUIT was implemented in four multi-site clinical trials (parent trials) supported by three National Institutes of Health institutes and included 50 associated specialty clinics from these parent trials. Using current data, we have 88% power or greater to detect a 0.15 or greater difference from the currently observed control proportion adjusting for clustering. We detected no differences in baseline matching criteria between intervention and control specialty clinics (all p values > 0.17).

CONCLUSION

RECRUIT was the first multi-site randomized control trial to examine the effectiveness of a trust-based continuous quality improvement intervention to increase minority recruitment into clinical trials. RECRUIT's innovations included its focus on building trust between specialist investigators and minority-serving physicians, the use of continuous quality improvement to tailor the intervention to each specialty clinic's specific racial/ethnic populations and barriers to minority recruitment, and the use of specialty clinics from more than one parent multi-site trial to increase generalizability. The effectiveness of the RECRUIT intervention will be determined after the completion of trial data collection and planned analyses.

Ethnic sensitivity assessment of the antibody-drug conjugate trastuzumab emtansine (T-DM1) in patients with HER2-positive locally advanced or metastatic breast cancer

PURPOSE

Trastuzumab emtansine (T-DM1) is indicated for previously treated HER2-positive metastatic breast cancer. Ethnic sensitivity assessment of T-DM1 was conducted using data from eight clinical studies to ensure that the clinically recommended dose is appropriate across ethnicities.

METHODS

Four approaches were used: (1) non-compartmental analysis (NCA) comparing pharmacokinetic parameters of T-DM1 and relevant analytes across ethnic groups, (2) population pharmacokinetic (popPK) analysis assessing the impact of ethnicity on pharmacokinetics, (3) comparison of T-DM1 pharmacokinetics in Japanese patients versus the global population, and (4) exposure-response analyses assessing the impact of ethnicity on safety and efficacy.

RESULTS

NCA pharmacokinetic parameters (T-DM1, total trastuzumab, DM1) were comparable across ethnic groups; mean cycle 1 T-DM1 AUCinf was 475, 442, and 518 day µg/mL for white (n = 461), Asian (n = 68), and others (n = 57), respectively. PopPK analysis showed that ethnicity (white, Asian, and others) was not a significant covariate for T-DM1 pharmacokinetics (n = 671). Additionally, visual predictive check plots indicated that observed pharmacokinetic profiles in Japanese patients (n = 42) were within the prediction interval generated from the final PopPK model. Exposure-response analyses showed that ethnicity was not a significant covariate impacting efficacy or hepatotoxicity risk, but there was a trend of greater thrombocytopenia risk among Asians versus non-Asians, which could not be explained by similar exposure between the ethnic groups. Most Asians with thrombocytopenia were able to continue T-DM1 using dose-adjustment rules recommended for the global population.

CONCLUSIONS

These results suggest that T-DM1 pharmacokinetics are comparable across ethnic groups and that use of the current dosing regimen is appropriate across ethnicities.

Use of the Foreign Studies: Transposition of the Results, Prediction of the Therapeutic Effects in the French Population, Modelling of the Public Health Interest

More and more frequently, the health authorities and the French assessment agencies are led to issue Marketing Authorizations (MAs), give opinions on the eligibility for reimbursement of drugs or to draft recommendations for clinical practice based on the results of foreign studies. The results of these studies are more or less difficult to transpose to French practice. These difficulties generate varying degrees of uncertainty concerning the effect to be expected of a drug. A more or less extensive loss of effect is sometimes even predictable. Some of the difficulties in transposition are discussed in this article and proposals for action are made in order to allow one, in the long term, to predict in the most precise manner possible the effects to be expected from a drug in the French population and be able to verify this prediction at an interval from its eligibility for reimbursement.

Exploring Willingness of Elder Chinese in Houston to Participate in Clinical Research

Background and objectives

Inadequate minority participation in clinical research can threaten the applicability and strength of scientific findings. Previous research suggests that trial participation rates are lowest among Asian Americans, compared to other groups. This study explored barriers to clinical research participation among elder Chinese living in Houston, Texas. Additionally we administered the Trust in Medical Researchers Scale (TIMRS), used previously in researching trust in medical researchers as related to research participation.

Design

In this mixed methods study, a semi-structured interview, including the TIMRS were administered to 30 adults of Chinese ancestry aged 50 years or older recruited from a Chinese community center. Interviews were conducted in English, Mandarin and Cantonese and independently coded and analyzed using thematic content analysis. TIMRS scores were calculated for participants.

Results

Participants were 70% female, 70% were 60 or elder, all were foreign born and on average lived in the US for 21.8 years. Participants perceived risks to research participation and preferred language concordant research staff. Interviewees were more willing to participate if they perceived personal and community health-related benefits. The overall TIMRS score was 23.9 (±5.0), lower than the overall TIMRS for Whites in a previous study (P < 0.001).

Conclusions

The barriers and facilitators to research participation confirmed previous research among Asians. Our participant TIMRS scores were consistent with decreased levels of trust observed in the original TIMRS study for African Americans as compared and lower than Whites. Employing strategies that utilize language concordant staff who build trust with participants may aid in recruiting elder Chinese, especially if the research is personally relevant to those being recruited.

The global conduct of cancer clinical trials: challenges and opportunities

The nature of clinical research has changed substantially over the last 2 decades, evolving from being centered almost exclusively in developed countries to a more global scenario that is increasingly involving less developed regions of the world. Pharmaceutical companies and some academic cooperative groups have been conducting challenging, large pivotal registration studies with multinational participation. The much more needed globalization of academic research demands particular attention and represents a worthwhile subject for a more profound discussion. The requirement of large sample sizes and the potential for fast recruitment leading to a speedy completion of clinical studies are probably the most important factors that have fueled globalization of studies. Reduced operational costs and the ability to expedite the regulatory approval of drugs in various countries or regions are also important drivers. Globalization of research should be seen as having a much wider effect in the societies involved, in particular, when we consider public health, economic, social, and ethical implications. Most importantly, the process of expanding the network of clinical research sites also fosters the integration and the development of closer relationships among investigators at a global level. We consider this an essential element that should remain a prominent element in the discussion. In this article, we address the underlying reasons for globalization and we highlight some of the scientific and ethical concerns arising as a consequence. Finally, some strategies to address and mitigate the challenges of conducting multinational clinical research are proposed.

Ethnic sensitivity assessment of fluticasone furoate/vilanterol in East Asian asthma patients from randomized double-blind multicentre Phase IIb/III trials

Background

Fluticasone furoate (FF)/vilanterol (VI) is a once daily (OD) inhaled corticosteroid/long-acting β₂-agonist combination asthma therapy approved in Japan and the EU. FF/VI efficacy and safety data from asthma studies including patients in East Asia were evaluated to assess ethnic sensitivity.

Methods

Randomized, double-blind, multicenter Phase IIb/III trials were assessed. Change from baseline relative to placebo or twice-daily fluticasone propionate 500 μg in trough FEV₁ was compared between patients from Japan (N = 148) and Not-Japan (N = 3,066; three studies). Adverse events (AEs), laboratory results, and electrocardiograms were compared between patients from Japan + Korea (N = 188) and Not-Japan + Korea (N = 3,840; five studies).

Results

For trough FEV₁, improvements from baseline (least-squares mean difference [95 % confidence interval]) were reported for FF/VI 100/25 μg OD versus placebo at Week 12 (Japan: 0.323 L [0.104–0.542]; Not-Japan: 0.168 L [0.095–0.241]). Improvements from baseline (least-squares mean change [standard error]) were reported with FF/VI 200/25 μg OD at Week 24 (Japan: 0.355 L [0.1152]; Not-Japan: 0.396 L [0.0313]). A greater proportion of patients from Japan + Korea versus Not-Japan + Korea reported AEs in all treatment arms including placebo (FF/VI 100/25 μg: 79 % versus 57 %; FF/VI 200/25 μg: 64 % versus 45 %; placebo: 41 % versus 23 %). There were no notable differences in treatment-related or class-related AEs. No clinically significant changes in electrocardiogram assessments or statistically significant differences in 24 h urinary cortisol excretion were observed between the Japan + Korea and Not-Japan + Korea cohorts.

Conclusions

Good efficacy and an acceptable safety profile were observed for FF/VI 100/25 μg and 200/25 μg OD in East Asian asthma patients; these globally recommended doses are appropriate for asthma patients in Japan.

Trial registration

Clinicaltrials.gov registration numbers: NCT01165138, NCT01134042, NCT01086384, NCT00603278, NCT00603382.

Electronic supplementary material

The online version of this article (doi:10.1186/s12890-015-0159-z) contains supplementary material, which is available to authorized users.

Single and Multiple Dose Pharmacokinetics, Pharmacodynamics and Safety of the Novel Lipoprotein-Associated Phospholipase A2 Enzyme Inhibitor Darapladib in Healthy Chinese Subjects: An Open Label Phase-1 Clinical Trial

Background and Objectives

Darapladib is a lipoprotein-associated phospholipase A₂ (Lp-PLA₂) inhibitor. This study evaluated the pharmacokinetics, pharmacodynamics and safety of darapladib in healthy Chinese subjects.

Methods

Twenty-four subjects received darapladib 160 mg orally, approximately 1 hour after a standard breakfast, as a single dose and once daily for 28 days. Non-compartmental methods were used to determine the single and multiple dose pharmacokinetics of darapladib and its metabolite SB-553253. Repeat dose Lp-PLA₂ activity and safety were evaluated.

Results

Systemic exposure (AUC_(0-T), Cmax geometric mean (CVb%)) of darapladib was higher after multiple-dosing (519 ng.h/mL (33.3%), 34.4 ng/mL (49.9%)) compared to single-dose administration (153 ng.h/mL (69.0%), 17.9 ng/mL (55.2%). The steady-state accumulation ratio was less than unity (Rs = 0.80), indicating time-dependent pharmacokinetics of darapladib. Darapladib steady-state was reached by Day 14 of once daily dosing. Systemic exposure to SB-553253 was lower than darapladib with median (SB-553253: darapladib) ratios for AUC_(0-τ) of 0.0786 for single dose and 0.0532 for multiple dose administration. On Day 28, pre-dose and maximum inhibition of Lp-PLA₂ activity was approximately 70% and 75% relative to the baseline value, respectively and was dependent of darapladib concentration. The most common adverse events (≥ 21% subjects) were abnormal faeces, abnormal urine odour, diarrhoea and nasopharyngitis.

Conclusion

Darapladib 160 mg single and repeat doses were profiled in healthy Chinese subjects. Single dose systemic exposure to darapladib in healthy Chinese subjects was consistent with that observed previously in Western subjects whereas steady-state systemic exposure was approximately 65% higher in Chinese than Western subjects. The Lp-PLA₂ activity and adverse event profile were similar in healthy Chinese and previous reports in Western subjects. Ethnic-specific dose adjustment of darapladib is not considered necessary for the Chinese population.

Trial Registration

ClinicalTrials.gov NCT02000804

Evaluating the Responsiveness to Therapeutic Change with Routine Outcome Monitoring: A Comparison of the Symptom Questionnaire-48 (SQ-48) with the Brief Symptom Inventory (BSI) and the Outcome Questionnaire-45 (OQ-45)

Assessment of psychological distress is important, because it may help to monitor treatment effects and predict treatment outcomes. We previously developed the 48-item Symptom Questionnaire (SQ-48) as a public domain self-report psychological distress instrument and showed good internal consistency as well as good convergent and divergent validity among clinical and non-clinical samples. The present study, conducted among psychiatric outpatients in a routine clinical setting, describes additional psychometric properties of the SQ-48. The primary focus is on responsiveness to therapeutic change, which to date has been rarely examined within psychiatry or clinical psychology. Since a questionnaire should also be stable when no clinically important change occurs, we also examined test-retest reliability within a test-retest design before treatment (n = 43). A pre-treatment/post-treatment design was used for responsiveness to therapeutic change, comparing the SQ-48 with two internationally widely used instruments: the Brief Symptom Inventory (n = 97) and the Outcome Questionnaire-45 (n = 109). The results showed that the SQ-48 has excellent test-retest reliability and good responsiveness to therapeutic change, without significant differences between the questionnaires in terms of responsiveness. In sum, the SQ-48 is a psychometrically sound public domain self-report instrument that can be used for routine outcome monitoring, as a benchmark tool or for research purposes. Copyright © 2015 John Wiley & Sons, Ltd. Key Practitioner Message The SQ-48 is developed as a public domain self-report questionnaire, in line with growing efforts to develop clinical instruments that are free of charge. The SQ-48 has excellent test-retest reliability and good responsiveness to therapeutic change or patient progress. There were no significant differences in terms of responsiveness between the SQ-48 and BSI or OQ-45. The SQ-48 can be used as a routine evaluation outcome measure for quality assurance in clinical practice. Providing feedback on patient progress via outcome measures could contribute to the enhancement of treatment outcomes.

Association of Extrarenal Adverse Effects of Posttransplant Immunosuppression With Sex and ABCB1 Haplotypes

Extrarenal adverse effects (AEs) associated with calcineurin inhibitor (CNI) and mycophenolic acid (MPA) occur frequently but are unpredictable posttransplant complications. AEs may result from intracellular CNI accumulation and low activity of P-glycoprotein, encoded by the ABCB1 gene. Since ABCB1 single nucleotide polymorphisms (SNPs) and sex influence P-glycoprotein, we investigated haplotypes and extrarenal AEs. A prospective, cross-sectional study evaluated 149 patients receiving tacrolimus and enteric coated mycophenolate sodium or cyclosporine and mycophenolate mofetil. Immunosuppressive AE assessment determined individual and composite gastrointestinal, neurologic, aesthetic, and cumulative AEs. Lipids were quantitated after 12-hour fast. ABCB1 SNPs: c.1236C>T (rs1128503), c.2677G>T/A (rs2032582), and c.3435C>T (rs1045642) were determined with haplotype associations computed using the THESIAS program, and evaluated by immunosuppression, sex and race using multivariate general linear models. Tacrolimus patients exhibited more frequent and higher gastrointestinal AE scores compared with cyclosporine with association to CTT (P = 0.018) and sex (P = 0.01). Aesthetic AE score was 3 times greater for cyclosporine with TTC haplotype (P = 0.005). Females had higher gastrointestinal (P = 0.022), aesthetic (P < 0.001), neurologic (P = 0.022), and cumulative AE ratios (P < 0.001). Total cholesterol (TCHOL), low-density lipoproteins (LDL), and triglycerides were higher with cyclosporine. The TTC haplotype had higher TCHOL (P < 0.001) and LDL (P = 0.005). Higher triglyceride (P = 0.034) and lower high-density lipoproteins (P = 0.057) were associated with TTT with sex-adjusted analysis. ABCB1 haplotypes and sex were associated with extrarenal AEs. Using haplotypes, certain female patients manifested more AEs regardless of CNI. Haplotype testing may identify patients with greater susceptibility to AEs and facilitate CNI individualization.

Comparing recruitment, retention, and safety reporting among geographic regions in multinational Alzheimer's disease clinical trials

INTRODUCTION

Most Alzheimer's disease (AD) clinical trials enroll participants multinationally. Yet, few data exist to guide investigators and sponsors regarding the types of patients enrolled in these studies and whether participant characteristics vary by region.

METHODS

We used data derived from four multinational phase III trials in mild to moderate AD to examine whether regional differences exist with regard to participant demographics, safety reporting, and baseline scores on the Mini Mental State Examination (MMSE), the 11-item Alzheimer's Disease Assessment Scale-Cognitive subscale (ADAS-cog11), the Clinical Dementia Rating scale Sum of Boxes (CDR-SB), the Alzheimer's Disease Cooperative Study-Activities of Daily Living Inventory (ADCS-ADL), and the Neuropsychiatric Inventory (NPI). We assigned 31 participating nations to 7 geographic regions: North America, South America/Mexico, Western Europe/Israel, Eastern Europe/Russia, Australia/South Africa, Asia, and Japan.

RESULTS

North America, Western Europe/Israel, and Australia/South Africa enrolled similar proportions of men, apolipoprotein E ε4 carriers, and participants with spouse study partners, whereas Asia, Eastern Europe/Russia, and South America/Mexico had lower proportions for these variables. North America and South America/Mexico enrolled older subjects, whereas Asia and South America/Mexico enrolled less-educated participants than the remaining regions. Approved AD therapy use differed among regions (range: 73% to 92%) and was highest in North America, Western Europe/Israel, and Japan. Dual therapy was most frequent in North America (48%). On the MMSE, North America, Western Europe/Israel, Japan, and Australia/South Africa had higher (better) scores, and Asia, South America/Mexico, and Eastern Europe/Russia had lower scores. Eastern Europe/Russia had more impaired ADAS-cog11 scores than all other regions. Eastern Europe/Russia and South America/Mexico had more impaired scores for the ADCS-ADL and the CDR-SB. Mean scores for the CDR-SB in Asia were milder than all regions except Japan. NPI scores were lower in Asia and Japan than in all other regions. Participants in North America and Western Europe/Israel reported more adverse events than those in Eastern Europe/Russia and Japan.

CONCLUSIONS

These findings suggest that trial populations differ across geographic regions on most baseline characteristics and that multinational enrollment is associated with sample heterogeneity. The data provide initial guidance with regard to the regional differences that contribute to this heterogeneity and are important to consider when planning global trials.

Efficacy and safety of fluticasone furoate/vilanterol (50/25 mcg; 100/25 mcg; 200/25 mcg) in Asian patients with chronic obstructive pulmonary disease: a randomized placebo-controlled trial

BACKGROUND AND OBJECTIVE

Three strengths of fluticasone furoate/vilanterol (FF/VI) were previously evaluated for the treatment of chronic obstructive pulmonary disease (COPD) in a program of global Phase 3 studies that included only a small subgroup of Asian patients. This study further evaluated the efficacy and safety of the same three strengths of FF/VI exclusively in Asian patients.

METHODS

A randomized, double-blind, placebo-controlled, parallel-group, multicenter study. Patients with post-bronchodilator FEV1/FVC ≤0.70, FEV1 ≤70% predicted and modified Medical Research Council score ≥2 were randomized (1:1:1:1) to placebo, FF/VI 50/25 mcg, 100/25 mcg or 200/25 mcg once daily via the ELLIPTA dry powder inhaler. The primary efficacy endpoint was change from baseline in trough FEV1 at Week 24.

RESULTS

The intent-to-treat population comprised 643 patients. Statistically significant (p < 0.001) improvements in trough FEV1 were observed with all strengths of FF/VI versus placebo at Week 24 (0.14-0.19 L). Reduction of supplemental albuterol use was observed with all strengths of FF/VI versus placebo. The incidence of on-treatment adverse events (AEs) was 48% with FF/VI 200/25 mcg and 37-40% with other treatments. The incidence of on-treatment serious AEs was 4-9% with FF/VI treatments versus 9% with placebo; however, the study only covered a 6 month treatment period and was not powered to assess effects on exacerbations. No clinically significant treatment effects versus placebo were identified for electrocardiogram, vital signs, 24 hour urinary cortisol excretion and pneumonia.

CONCLUSIONS

All strengths of FF/VI improved lung function with an acceptable safety profile. There is no evidence to suggest that dose adjustment may be required in Asian patients using FF/VI 100/25 mcg for the treatment of COPD.

CLINICAL TRIAL REGISTRATION

NCT01376245.

Safety, tolerability, pharmacokinetics, and pharmacodynamics of losmapimod in healthy Japanese volunteers

This phase 1 study characterized the safety, tolerability, pharmacokinetics, and pharmacodynamics of losmapimod and its metabolite GSK198602 following single and repeat doses of oral losmapimod in healthy Japanese volunteers. Subjects (n = 41) received single oral doses of losmapimod (2.5, 7.5, 20 mg) or matching placebo on 3 separate days (n = 20) or losmapimod 7.5 mg or matching placebo twice daily for 14 days (n = 21). Assessments included maximum observed plasma concentration (Cmax ), time to Cmax (Tmax ), apparent terminal-phase half-life (t1/ )2 , area under the curve (AUC), and change in C-reactive protein and phosphorylated heat shock protein 27 levels. No serious adverse events occurred during the study, and there were no safety concerns regarding clinical laboratory parameters, 12-lead electrocardiogram, or vital signs. The losmapimod Tmax was 3-4 hours, and the mean t1/2 was approximately 7.9-9.0 hours, with no appreciable difference in Tmax and apparent clearance following oral dosing between dosing regimens. Single and repeat oral doses of losmapimod were well tolerated in healthy Japanese volunteers. The Tmax of GSK198602 was similar to and t1/2 was slightly longer than those of losmapimod. Approximate dose-proportional increases in exposure to losmapimod and GSK198602 were observed in AUC with single-dose administration. Repeat-dose trough concentrations reached steady state within 2 days, with an observed accumulation ratio of 1.56 and 1.91 for losmapimod and GSK198602, respectively.

Pharmacokinetics and tolerability of inhaled umeclidinium and vilanterol alone and in combination in healthy Chinese subjects: a randomized, open-label, crossover trial

Inhaled umeclidinium (UMEC) and the combination of inhaled UMEC with vilanterol (UMEC/VI) are approved maintenance treatments for chronic obstructive pulmonary disease in the US and EU. This was a randomized, open-label, three-period crossover, single- and repeat-dose study to assess the pharmacokinetics (PK), safety, and tolerability of inhaled UMEC/VI 62.5/25 μg (delivering 55/22 μg) and UMEC/VI 125/25 μg (delivering 113/22 μg) compared with their monotherapy components (UMEC 62.5 μg, UMEC 125 μg and, VI 25 μg [delivering 55, 113, and 22 μg, respectively]) in healthy Chinese subjects (n=20). UMEC and VI were rapidly absorbed following single and repeat dosing (time to maximum plasma concentration [t_max]: UMEC = 5 min; VI = 5 min). The median t_last was 2–4 h for UMEC and 1–2 h for VI following single doses of UMEC/VI and UMEC monotherapy (both doses). UMEC reached steady-state prior to Day 10; steady-state for VI could not be assessed. UMEC accumulation following repeat dosing was 11–34% based on C_max and 19–59% based on area under the concentration-time curve from time zero to 2 h (AUC_(0-2)). VI accumulation following repeat dosing was 25–66% based on C_max and 17–43% based on AUC_(0-2). The evidence was not sufficient to suggest that systemic exposure was substantially different between UMEC/VI combination therapy and the constituent monotherapies following single or repeat dosing. Following both single- and repeat-dose administration, the inter-subject coefficient of variation for all UMEC PK parameter estimates ranged from 12% to 165% for all treatments, indicating a wide range of variability in inhaled PK parameters. Twelve subjects experienced ≥1 adverse event (AE). Six subjects experienced ≥1 treatment-related AE; the most commonly reported treatment-related AE was chest discomfort (n=3 [15%]). No clinically important changes in vital signs or electrocardiogram parameters were reported. These data suggest that single- and repeat-dose administration of UMEC/VI combination therapy in healthy Chinese subjects did not result in substantial differences in systemic exposure compared with UMEC and VI as monotherapies.

Fluticasone furoate/vilanterol 200/25 mcg in Asian asthma patients: a randomized trial

BACKGROUND

This study investigated the efficacy and safety of the inhaled corticosteroid (ICS)/long-acting beta2-agonist (LABA) combination fluticasone furoate (FF)/vilanterol (VI) in Asian asthma patients.

METHODS

A 12-week, double-blind, double-dummy, active-comparator, parallel-group, multicenter study. 309 Asian asthma patients (≥12 years, uncontrolled with high-strength ICS or mid-dose ICS/LABA) were randomized (1:1) and included in the intent-to-treat population; 155 received once-daily FF/VI 200/25 mcg and 154 received twice-daily fluticasone propionate (FP) 500 mcg. The primary endpoint was change from baseline in daily evening peak expiratory flow (PEF) averaged over 12 weeks. Secondary endpoints were mean change from baseline in % rescue-free 24-h periods, daily morning PEF, % symptom-free 24-h periods, and overall Asthma Quality of Life Questionnaire score. Safety assessments were performed.

RESULTS

For change from baseline in daily evening PEF, the adjusted mean treatment difference for FF/VI versus FP of 28.5 L/min (95% confidence interval [CI]: 20.1, 36.9) was clinically and statistically significant (p < 0.001). For change from baseline in % rescue-free 24-h periods, the adjusted mean treatment difference (1.0%; 95% CI: -7.3, 9.2) was not statistically significant (p = 0.821). Statistical significance could not be inferred for the remaining endpoints due to the statistical hierarchy employed. Incidence of on-treatment adverse events was similar with FF/VI (26%; 3% treatment-related; n = 1 serious) and FP (27%; 3% treatment-related; n = 2 serious); none were fatal. No further safety concerns were identified.

CONCLUSIONS

FF/VI improved evening PEF over 12 weeks versus FP in Asian patients, with a similar safety profile. The results are generally consistent with a global study comparing the same treatments.