Special population considerations and regulatory affairs for clinical research

How PBPK Can Help to Understand Old Drugs and Inform their Dosing in Elderly: Amantadine Case Study

Amantadine, despite being on the market for 55 years, has several unknown aspects of its pharmacokinetics especially related to the influence of covariates such as age, disease, or interactions linked to amantadine's renal elimination. As amantadine is used in Parkinson's disease and is considered a potential candidate in COVID treatment and other diseases, there is an unmet need for thorough understanding of its pharmacokinetic in special populations, such as the elderly. We aimed to mechanistically describe amantadine pharmacokinetics in healthy subjects and shed some light on the differences in drug behavior between healthy volunteers (18-65 years) and an elderly/geriatric population (65-98 years) using PBPK modeling and simulation. The middle-out PBPK model includes mechanistic description of drug renal elimination, specifically an organic cation transporter (OCT)2-mediated electrogenic bidirectional transport (basolateral) and multidrug and toxic compound extrusion (MATE)1-mediated efflux (apical). The model performance was verified against plasma and urine data reported after single and multiple dose administration in healthy volunteers and elderly patients from 18 independent studies. The ratios of predicted vs. observed maximal plasma concentration and area under the concentration-time curve values were within 1.25-fold. The model illustrates that renal transporter activity is expected to decrease in healthy elderly compared to healthy volunteers, which is in line with literature proteomic data for OCT2. The model was applied to assess the potential of reaching toxicity-related plasma concentrations in different age groups of geriatric subjects.

Evaluation of gender differences in the pharmacokinetics of oral zileuton nanocrystalline formulation using a rat model

Zileuton is a leukotriene inhibitor used to treat asthma. As a BCS class II drug it exhibits challenges with solubility which likely impact its absorption. As patient gender significantly impacts the pharmacokinetics of many drugs, this study aimed to investigate potential gender-based pharmacokinetic differences after oral zileuton administration in rats. Male and female Sprague Dawley rats received single oral gavage doses of pure zileuton as an active pharmaceutical ingredient (30 mg/kg body weight (bw)), physical mixture (PM; at 30 mg/kg bw of the formulation contains zileuton, kollidon VA64 fine, dowfax2A1 and trehalose), and nanocrystalline formulation of zileuton (NfZ; at 30 mg/kg bw of the formulation). Plasma, tissue, and urine concentrations were quantified using high performance liquid chromatography (HPLC). Noncompartmental pharmacokinetic analysis showed higher zileuton levels in the plasma of female versus male rats across all evaluated forms of zileuton (API, PM, and NfZ). Female rats demonstrated higher peak plasma concentrations (Cmax) and increased area under the plasma concentration-time curve (AUC) relative to males, regardless of formulation. These findings reveal substantial gender disparities in the pharmacokinetics of zileuton in the rat model. This study emphasizes the critical need to evaluate gender differences during preclinical drug development to enable gender-based precision dosing strategies for equivalent efficacy/safety outcomes in male and female patients. Additional studies are warranted to investigate underlying mechanisms of such pharmacokinetic gender divergences.

In the land of not-unhappiness: On the state-of-the-art of targeting aging and age-related diseases by biomedical research

The concept of the Land of Not-Unhappiness refers to the potential achievement of eliminating the pathologies of the aging process. To inform of how close we are to settling in the land, we summarize and review the achievements of research on anti-aging interventions over the last hundred years with a specific focus on strategies that slow down metabolism, compensate for aging-related losses, and target a broad range of age-related diseases. We critically evaluate the existing interventions labeled as "anti-aging," such as calorie restriction, exercise, stem cell administration, and senolytics, to provide a down-to-earth evaluation of their current applicability in counteracting aging. Throughout the text, we have maintained a light tone to make it accessible to non-experts in biogerontology, and provide a broad overview for those considering conducting studies, research, or seeking to understand the scientific basis of anti-aging medicine.

Global prevalence of onychomycosis in general and special populations: An updated perspective

BACKGROUND

Onychomycosis is a chronic nail disorder commonly seen by healthcare providers; toenail involvement in particular presents a treatment challenge.

OBJECTIVE

To provide an updated estimate on the prevalence of toenail onychomycosis.

METHODS

We conducted a literature search using PubMed, Embase and Web of Science. Studies reporting mycology-confirmed diagnoses were included and stratified into (a) populations-based studies, and studies that included (b) clinically un-suspected and (c) clinically suspected patients.

RESULTS

A total of 108 studies were included. Based on studies that examined clinically un-suspected patients (i.e., with or without clinical features suggestive of onychomycosis), the pooled prevalence rate of toenail onychomycosis caused by dermatophytes was 4% (95% CI: 3-5) among the general population; special populations with a heightened risk include knee osteoarthritis patients (RR: 14.6 [95% CI: 13.0-16.5]), chronic venous disease patients (RR: 5.6 [95% CI: 3.7-8.1]), renal transplant patients (RR: 4.7 [95% CI: 3.3-6.5]), geriatric patients (RR: 4.7 [95% CI: 4.4-4.9]), HIV-positive patients (RR: 3.7 [95% CI: 2.9-4.7]), lupus erythematosus patients (RR: 3.1 [95% CI: 1.2-6.3]), diabetic patients (RR: 2.8 [95% CI: 2.4-3.3]) and hemodialysis patients (RR: 2.8 [95% CI: 1.9-4.0]). The prevalence of onychomycosis in clinically suspected patients was significantly higher likely due to sampling bias. A high degree of variability was found in a limited number of population-based studies indicating that certain pockets of the population may be more predisposed to onychomycosis. The diagnosis of non-dermatophyte mould onychomycosis requires repeat sampling to rule out contaminants or commensal organisms; a significant difference was found between studies that performed single sampling versus repeat sampling. The advent of PCR diagnosis results in improved detection rates for dermatophytes compared to culture.

CONCLUSION

Onychomycosis is an underrecognized healthcare burden. Further population-based studies using standardized PCR methods are warranted.

Safety and effectiveness of certolizumab pegol in Japanese patients with rheumatoid arthritis: Up to 3-year results from a postmarketing surveillance study

OBJECTIVES

To report up to 3-year safety and effectiveness of certolizumab pegol (CZP) in Japanese patients with rheumatoid arthritis from a postmarketing surveillance study.

METHODS

Patients enrolled previously completed 24 weeks of CZP in the 24-week postmarketing surveillance study. Adverse drug reactions (ADRs) were recorded for patients who received ≥1 CZP dose. Effectiveness outcomes were 28-joint Disease Activity Score with erythrocyte sedimentation rate and European Alliance of Associations for Rheumatology response. Week 24-156 safety and Week 0-52 effectiveness data are reported here.

RESULTS

A total of 781 patients were enrolled, with 735 and 376 patients evaluated for safety and effectiveness, respectively. Within the safety set, 17.8% (131/735) of patients reported ADRs; 9.4% (69/735) reported serious ADRs. Among patients with history of respiratory, thoracic, and mediastinal disorders, 38.4% (28/73) reported ADRs. The most frequent ADRs were infections and infestations (11.8%; 87/735); skin and subcutaneous tissue disorders (1.9%; 14/735); respiratory, thoracic, and mediastinal disorders (1.6%; 12/735). Mean 28-joint Disease Activity Score with erythrocyte sedimentation rate reduced from 4.6 (Week 0) to 2.8 (Week 52). At Week 52, 51.8% (161/311) of patients achieved European Alliance of Associations for Rheumatology Good response.

CONCLUSIONS

The long-term safety and effectiveness of CZP in the real-world setting in Japan were consistent with previously reported data; no new safety signals were identified.

Adult and pediatric physiologically-based biopharmaceutics modeling to explain lamotrigine immediate release absorption process

Physiologically-based biopharmaceutics modeling (PBBM) has potential to accelerate the development of new drug and formulations. An important application of PBBM is for special populations such as pediatrics that have pharmacokinetics dependent on the maturation process. Lamotrigine (LTG) is a Biopharmaceutics Classification System (BCS) II drug and is widely prescribed. Therefore, the goal of this study was to assess the biopharmaceutics risk of the low-soluble drug LTG when the ontogeny on gastrointestinal tract (GIT) physiological parameters are considered. An oral physiologically-based pharmacokinetic model and a PBBM were developed and verified using GastroPlus™ software for both adults and children (2-12 years old, 12-52 kg). The biopharmaceutics properties and GIT physiological parameters were evaluated by sensitivity analysis. High doses were simulated assuming a worst case scenario, that is, the dose of 200 mg for adults and 5 mg/kg (up to the maximum of 200 mg) for 2-year-old children. Although several authors have suggested that ontogeny may have an effect on gastrointestinal fluid volume, our study found no evidence of interference between fluid and dose volumes with in vivo dissolution of LTG. The most impactful parameter was found to be the gastric transit time. Therefore, the hypothesis is developed to examine whether LTG exhibits characteristics of a BCS II classification in vitro while showing BCS I-like behavior in vivo. This hypothesis could act as a base for conducting novel studies on model-informed precision dosing, tailored to specific populations and clinical conditions. In addition, it could be instrumental in assessing the influence of various release profiles on in vivo performance for both adult and pediatric populations.

Reconsideration of the current models of estimated kidney function-based drug dose adjustment in older adults: The role of biological age

Human lifespan has increased from a median of 46.5 years in 1950 to 71.7 years in 2022. As people age, one of the inevitable consequences is a decline in kidney function and glomerular filtration rate (GFR) which can have direct or indirect effects on the pharmacokinetic and pharmacodynamic profiles of many drugs. Numerous equations have been developed to generate estimated GFR (eGFR) using the two principal biomarkers: serum creatinine and serum cystatin C. However, the trajectory of changes with aging is dissimilar in these equations. In addition, there is recognition that chronological age (lifespan) often does not reflect biological age (healthspan) as an essential parameter in kidney function equations. In the past decade, there has been an increasing interest in quantifying biological age and new commercially available assays have entered the marketplace. In this narrative review, we illustrate how dominant equations of eGFR model the fractional change in this parameter very differently across chronological age. In addition, we review various biological age indicators (aging clocks) and challenges to their application in clinical practice. Importantly, by comparing vancomycin's mean clearance as a drug with limited metabolism and unchanged elimination between two age milestones in some recent population pharmacokinetic models, we show how efforts to quantify kidney function in older adults optimally remain under-explored, particularly those at the upper end of their lifespan. We also propose considering new models that integrate biological age as a new pathway to improve precision drug dosing in older adults.

Guidance on interim analysis methods in clinical trials

Interim analyses in clinical trials can take on a multitude of forms. They are often used to guide Data and Safety Monitoring Board (DSMB) recommendations to study teams regarding recruitment targets for large, later-phase clinical trials. As collaborative biostatisticians working and teaching in multiple fields of research and across a broad array of trial phases, we note the large heterogeneity and confusion surrounding interim analyses in clinical trials. Thus, in this paper, we aim to provide a general overview and guidance on interim analyses for a nonstatistical audience. We explain each of the following types of interim analyses: efficacy, futility, safety, and sample size re-estimation, and we provide the reader with reasoning, examples, and implications for each. We emphasize that while the types of interim analyses employed may differ depending on the nature of the study, we would always recommend prespecification of the interim analytic plan to the extent possible with risk mitigation and trial integrity remaining a priority. Finally, we posit that interim analyses should be used as tools to help the DSMB make informed decisions in the context of the overarching study. They should generally not be deemed binding, and they should not be reviewed in isolation.

Systemic treatment of psoriasis in special population

Psoriasis is a common skin disorder affecting approximately 1% of the general population. The treatment of psoriasis depends on the body surface area involvement, quality of life impairment and associated co-morbidities. Special population comprising of pregnant women, lactating mothers, elderly individuals and children, is more vulnerable. They are not included in drug trials; rendering the data for use of systemic treatment scant and is mainly based on anecdotal evidence. In this narrative review, we discuss systemic treatment options in this special population. Though couples planning a family are not considered a special population, they form a subset that require special therapeutic consideration and have also been included in this review.

Recent clinical trials with stem cells to slow or reverse normal aging processes

Aging is associated with a decline in the regenerative potential of stem cells. In recent years, several clinical trials have been launched in order to evaluate the efficacy of mesenchymal stem cell interventions to slow or reverse normal aging processes (aging conditions). Information concerning those clinical trials was extracted from national and international databases (United States, EU, China, Japan, and World Health Organization). Mesenchymal stem cell preparations were in development for two main aging conditions: physical frailty and facial skin aging. With regard to physical frailty, positive results have been obtained in phase II studies with intravenous Lomecel-B (an allogeneic bone marrow stem cell preparation), and a phase I/II study with an allogeneic preparation of umbilical cord-derived stem cells was recently completed. With regard to facial skin aging, positive results have been obtained with an autologous preparation of adipose-derived stem cells. A further sixteen clinical trials for physical frailty and facial skin aging are currently underway. Reducing physical frailty with intravenous mesenchymal stem cell administration can increase healthy life expectancy and decrease costs to the public health system. However, intravenous administration runs the risk of entrapment of the stem cells in the lungs (and could raise safety concerns). In addition to aesthetic purposes, clinical research on facial skin aging allows direct evaluation of tissue regeneration using sophisticated and precise methods. Therefore, research on both conditions is complementary, which facilitates a global vision.

Sex Differences in Pain and Its Treatment

Pain is a highly personal experience. Pain is often considered to be a purely neurologic phenomenon, but in actuality, it is a combination of both sensory and emotional experiences. This has sometimes been translated clinically toward a more mechanistic approach to the assessment and treatment of pain instead of one that does not discount pain mechanisms, but also is more inclusive of the need for humanism - considering the individual. In today's medical environment, more than ever before there is a significant amount of attention being paid to educating clinicians to better understand that several physiological, neurophysiological, and psychosocial factors can significantly impact responses to pain. The composition of these factors will be unique to that individual's life narrative, context, sex, and prior life experiences. Thus, the concept that a templated approach to pain assessment and pharmacotherapeutic treatment planning should not be expected to provide optimal patient satisfaction and treatment outcomes in the majority. The hypotheses that there may be sex-based differences in the pain experience in a variety of ways including pain sensitivity, tolerance to pain, threshold at which something becomes painful, and the effectiveness of endogenous pain modulation systems are not new and have been well represented in the literature. This chapter reviews important key findings in the scientific literature with respect to sex-based differences in pain and pain responses to experimentally induced painful stimuli, pain experienced in commonly occurring painful medical conditions, and variations in responses to pain treatments. Possible explanations to account for observed differences or similarities will also be discussed.

Predicting transporter mediated drug-drug interactions via static and dynamic physiologically based pharmacokinetic modeling: A comprehensive insight on where we are now and the way forward

The greater utilization and acceptance of physiologically-based pharmacokinetic (PBPK) modeling to evaluate the potential metabolic drug-drug interactions is evident by the plethora of literature, guidance's, and regulatory dossiers available in the literature. In contrast, it is not widely used to predict transporter-mediated DDI (tDDI). This is attributed to the unavailability of accurate transporter tissue expression levels, the absence of accurate in vitro to in vivo extrapolations (IVIVE), enzyme-transporter interplay, and a lack of specific probe substrates. Additionally, poor understanding of the inhibition/induction mechanisms coupled with the inability to determine unbound concentrations at the interaction site made tDDI assessment challenging. Despite these challenges, continuous improvements in IVIVE approaches enabled accurate tDDI predictions. Furthermore, the necessity of extrapolating tDDI's to special (pediatrics, pregnant, geriatrics) and diseased (renal, hepatic impaired) populations is gaining impetus and is encouraged by regulatory authorities. This review aims to visit the current state-of-the-art and summarizes contemporary knowledge on tDDI predictions. The current understanding and ability of static and dynamic PBPK models to predict tDDI are portrayed in detail. Peer-reviewed transporter abundance data in special and diseased populations from recent publications were compiled, enabling direct input into modeling tools for accurate tDDI predictions. A compilation of regulatory guidance's for tDDI's assessment and success stories from regulatory submissions are presented. Future perspectives and challenges of predicting tDDI in terms of in vitro system considerations, endogenous biomarkers, the use of empirical scaling factors, enzyme-transporter interplay, and acceptance criteria for model validation to meet the regulatory expectations were discussed.

Dupilumab for the treatment of adult atopic dermatitis in special populations

BACKGROUND

Special populations (SPs) involve people who require additional consideration in clinical research. Effectiveness of treatment or occurrence of side effects may be different in SPs with respect to not-SPs.

OBJECTIVES

To retrospectively compare the effectiveness and safety of dupilumab in AD treatment of SPs versus not-SPs.

METHODS

A 52-weeks retrospective study was performed enrolling patients with a diagnosis of moderate-to-severe AD undergoing treatment with dupilumab at labelled dosage. Patients were divided in Group A (SPs patients) and Group B (not-SPs patients). Disease severity was assessed using Eczema Area Severity Index (EASI), Pruritus-Numerical Rating Scale (P-NRS), and Dermatology Life Quality Index (DLQI) score at baseline and after 4 weeks (W4), W16, W24, and W52.

RESULTS

A total of 263 patients were enrolled and divided in Group A (25) and Group B (238). SPs included history of cancer, severe kidney failure, viral hepatitis, neurological diseases, acquired immunodeficiency syndrome, and transplanted patients. A statistically significant reduction of EASI, DLQI, and P-NRS was assessed in both groups at each follow-up visit (p < 0.0001), without significant differences between the groups. No differences were recorded for safety.

CONCLUSIONS

There are not significant differences between SPs and not-SPs as regards effectiveness and safety of dupilumab in AD management.

The Promise of Nanotechnology in Personalized Medicine

Both personalized medicine and nanomedicine are new to medical practice. Nanomedicine is an application of the advances of nanotechnology in medicine and is being integrated into diagnostic and therapeutic tools to manage an array of medical conditions. On the other hand, personalized medicine, which is also referred to as precision medicine, is a novel concept that aims to individualize/customize therapeutic management based on the personal attributes of the patient to overcome blanket treatment that is only efficient in a subset of patients, leaving others with either ineffective treatment or treatment that results in significant toxicity. Novel nanomedicines have been employed in the treatment of several diseases, which can be adapted to each patient-specific case according to their genetic profiles. In this review, we discuss both areas and the intersection between the two emerging scientific domains. The review focuses on the current situation in personalized medicine, the advantages that can be offered by nanomedicine to personalized medicine, and the application of nanoconstructs in the diagnosis of genetic variability that can identify the right drug for the right patient. Finally, we touch upon the challenges in both fields towards the translation of nano-personalized medicine.

Drug-Drug Interactions in People Living with HIV at Risk of Hepatic and Renal Impairment: Current Status and Future Perspectives

Despite the advancement of antiretroviral therapy (ART) for the treatment of human immunodeficiency virus (HIV), drug–drug interactions (DDIs) remain a relevant clinical issue for people living with HIV receiving ART. Antiretroviral (ARV) drugs can be victims and perpetrators of DDIs, and a detailed investigation during drug discovery and development is required to determine whether dose adjustments are necessary or coadministrations are contraindicated. Maintaining therapeutic ARV plasma concentrations is essential for successful ART, and changes resulting from potential DDIs could lead to toxicity, treatment failure, or the emergence of ARV‐resistant HIV. The challenges surrounding DDI management are complex in special populations of people living with HIV, and often lack evidence‐based guidance as a result of their underrepresentation in clinical investigations. Specifically, the prevalence of hepatic and renal impairment in people living with HIV are between five and 10 times greater than in people who are HIV‐negative, with each condition constituting approximately 15% of non‐AIDS‐related mortality. Therapeutic strategies tend to revolve around the treatment of risk factors that lead to hepatic and renal impairment, such as hepatitis C, hepatitis B, hypertension, hyperlipidemia, and diabetes. These strategies result in a diverse range of potential DDIs with ART. The purpose of this review was 2‐fold. First, to summarize current pharmacokinetic DDIs and their mechanisms between ARVs and co‐medications used for the prevention and treatment of hepatic and renal impairment in people living with HIV. Second, to identify existing knowledge gaps surrounding DDIs related to these special populations and suggest areas and techniques to focus upon in future research efforts.

Translation of Pharmacodynamic Biomarkers of Antibiotic Efficacy in Specific Populations to Optimize Doses

Antibiotic efficacy determination in clinical trials often relies on non-inferiority designs because they afford smaller study sample sizes. These efficacy studies tend to exclude patients within specific populations or include too few patients to discern potential differences in their clinical outcomes. As a result, dosing guidance in patients with abnormal liver and kidney function, age across the lifespan, and other specific populations relies on drug exposure-matching. The underlying assumption for exposure-matching is that the disease course and the response to the antibiotic are similar in patients with and without the specific condition. While this may not be the case, clinical efficacy studies are underpowered to ensure this is true. The current paper provides an integrative review of the current approach to dose selection in specific populations. We review existing clinical trial endpoints that could be measured on a more continuous rather than a discrete scale to better inform exposure-response relationships. The inclusion of newer systemic biomarkers of efficacy can help overcome the current limitations. We use a modeling and simulation exercise to illustrate how an efficacy biomarker can inform dose selection better. Studies that inform response-matching rather than exposure-matching only are needed to improve dose selection in specific populations.

Orodispersible films: Conception to quality by design

Orodispersible films (ODFs) are ultra-thin, stamp-sized, elegant, portable and patient-centric pharmaceutical dosage forms that do not need water to be ingested. They are particularly useful for paediatric and geriatric patient populations with special needs such as dysphagia, Parkinson's disease, and oral cancer. Accordingly, they hold tremendous potential in gaining patient compliance, convenience and pharmacotherapy. In the present review, conception and evolution of ODFs as a product and its technology are discussed. The review continues by providing overview about the potential of ODFs as carriers for delivering drugs, herbal extracts, probiotics and vaccines. Besides, strategies employed in drug cargo loading, taste masking of bitter drugs and enhancing drug stability are discussed. Finally, the review concludes by providing a brief overview about quality by design (QbD) principles in development of ODFs.

Systematic review of research focused on pregnant and postpartum women living with HIV: A relational ethics perspective

Historically, maternal HIV research has focused on prevention of mother-to-child transmission and child outcomes, with little focus on the health outcomes of mothers. Over the course of the HIV epidemic, the approach to including pregnant women in research has shifted. The current landscape lends itself to reviewing the public health ethics of this research. This systematic review aims to identify ethical barriers and considerations for including pregnant and postpartum women living with HIV in treatment adherence and retention research. We completed a systematic literature review following PRISMA guidelines with analysis using a relational ethics perspective. The included studies (n = 7) identified ethical barriers related to (a) women research participants as individuals, (b) partner and family dynamics, (c) community perspectives on research design and conduct, and (d) policy and regulatory implications. These broader contextual factors will yield research responsive to, and respectful of, the needs of pregnant and postpartum women living with HIV. While current regulatory and policy environments may be slow to change, actions can be taken now to foster enabling environments for research. We suggest that a relational approach to public health ethics can best support the needs of pregnant and postpartum women living with HIV; acknowledging this population as systematically disadvantaged and inseparable from their communities will best support the health of this population.

Nanoparticulate Drug Delivery Strategies to Address Intestinal Cytochrome P450 CYP3A4 Metabolism towards Personalized Medicine

Drug dosing in clinical practice, which determines optimal efficacy, toxicity or ineffectiveness, is critical to patients' outcomes. However, many orally administered therapeutic drugs are susceptible to biotransformation by a group of important oxidative enzymes, known as cytochrome P450s (CYPs). In particular, CYP3A4 is a low specificity isoenzyme of the CYPs family, which contributes to the metabolism of approximately 50% of all marketed drugs. Induction or inhibition of CYP3A4 activity results in the varied oral bioavailability and unwanted drug-drug, drug-food, and drug-herb interactions. This review explores the need for addressing intestinal CYP3A4 metabolism and investigates the opportunities to incorporate lipid-based oral drug delivery to enable precise dosing. A variety of lipid- and lipid-polymer hybrid-nanoparticles are highlighted to improve drug bioavailability. These drug carriers are designed to target different intestinal regions, including (1) local saturation or inhibition of CYP3A4 activity at duodenum and proximal jejunum; (2) CYP3A4 bypass via lymphatic absorption; (3) pH-responsive drug release or vitamin-B12 targeted cellular uptake in the distal intestine. Exploitation of lipidic nanosystems not only revives drugs removed from clinical practice due to serious drug-drug interactions, but also provide alternative approaches to reduce pharmacokinetic variability.

Updated analysis of pediatric clinical studies registered in ClinicalTrials.gov, 2008-2019

Background

Since the national clinical trials registry (ClinicalTrials.gov) launched in February 2000, more than 360,000 research studies in the United States and over 200 countries have registered. As the characteristics of pediatric clinical studies keep changing over time and the results-reporting mechanism is under evolving, to know about the relevant updates of data elements and the effect of policies on the quality of reporting results is significant.

Methods

In this research, 53,060 clinical studies related to children registered from January 2008 to December 2019 were downloaded from ClinicalTrials.gov on August 1st, 2020. Different types of studies and critical categorical variables were identified, based on which, Cochran-Armitage test was performed to explore temporal trend of study characteristics and common pediatric clinical conditions in four time subsets. Further, to examine heterogeneity among subgroups (funding sources, funding sites, pediatric clinical conditions,etc), chi-squared test was applied.

Results

A total of 36,136 clinical trials and 16,692 observational studies were identified during the study period. The pediatric clinical trials increased from 7,029 (January 2008–December 2010) to 11,738 (January 2017–December 2019). The number of missing data has declined, with the maximum extent decline from 3.7 to 0.0% (Z = − 15.90, p <  0.001). Drug trials decreased from 48.8 to 28.9% (Z = − 24.68, p <  0.001). Behavioral trials, on the other hand, increased from 12.6 to 20.4% (Z = 12.28, p <  0.001). Most pediatric clinical trials were small-scale (58.9% enrolling 1–100 participants), single-site (61.4%) and funded neither by industry nor by the NIH (59.2%). The proportion of reporting study results varied by study type (χ² = 1,256.8, p <  0.001), lead sponsor (χ² = 4,545.6, p <  0.001), enrollment (χ² = 29.4, p <  0.001) and trial phase (χ² = 218.8, p <  0.001).

Conclusion

Pediatric clinical studies registered in ClinicalTrials.gov were dominated by small-scale interventional trials, containing significant heterogeneity in funding sources, funding sites, pediatric clinical conditions and study characteristics. Although the results database has evolved in the past decade, efforts to strengthen the practice of systematic reporting must be continued.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12887-021-02658-4.

Concept and utility of population pharmacokinetic and pharmacokinetic/pharmacodynamic models in drug development and clinical practice

Due to frequent clinical trial failures and consequently fewer new drug approvals, the need for improvement in drug development has, to a certain extent, been met using model-based drug development. Pharmacometrics is a part of pharmacology that quantifies drug behaviour, treatment response and disease progression based on different models (pharmacokinetic - PK, pharmacodynamic - PD, PK/PD models, etc.) and simulations. Regulatory bodies (European Medicines Agency, Food and Drug Administration) encourage the use of modelling and simulations to facilitate decision-making throughout all drug development phases. Moreover, the identification of factors that contribute to variability provides a basis for dose individualisation in routine clinical practice. This review summarises current knowledge regarding the application of pharmacometrics in drug development and clinical practice with emphasis on the population modelling approach.

Prevalence of medication discrepancies in pediatric patients transferred between hospital wards

Background Children are more susceptible to harm from medication errors and adverse drug reactions when compared to adults. Such events may occur from medication discrepancies while transitioning patients throughout the healthcare system. Contributing factors include medication discontinuity and lack of information by the healthcare team. Objective To analyze the prevalence of medication discrepancies in transition points of care in a pediatric department. Setting Pediatric department of a public hospital in Northeast Brazil. Method A cross-sectional study was carried out from August 2017 to March 2018. Data collection consisted of the following steps: collection of sociodemographic data, clinical interview with the patient's caregiver, registration of patient prescriptions, and evaluation of medical records. Medication discrepancies were classified as intentional and unintentional. The unintentional medication discrepancies were classified as omission of medication, therapeutic duplicity, and differences in dose, frequency, or route of administration. Main outcomes measure Discrepancy profile identified at admission, internal transfer and hospital discharge. Results Among the 114 patients included in the study, 85 (74.5%) patients had at least one unintentional medication discrepancy, of which 16 (14.0%) patients presented medication discrepancies at hospital admission, 42 (36.8%) patients at internal transfer, and 52 (45.6%) patients during discharge. Omission of medication represented 20 (74.1%) errors at admission, 26 (37.7%) errors at internal transfer, and 80 (100.0%) errors at hospital discharge. Conclusions The main transition points of care where unintentional discrepancies occurred in the studied pediatric department were at internal transfer and hospital discharge, with omission being the most common type of unintentional discrepancy.

Identification and analysis of ongoing registered clinical intervention trials on COVID-19

Introduction

The World Health Organization declared the disease caused by the novel coronavirus (SARS-CoV-2), a pandemic on March 11, 2020. Several studies have been proposed and started since then, mainly covering prevention, diagnosis, management, and treatment.

Objective

To identify and categorize all intervention studies up to the end of May related to SARS-CoV-2 infection, according to population and geo-graphical location (emphasis in Latin America) and to verify if there is any correlation according to purpose, phase, and recruitment status.

Methods

One thousand six hundred seventy-two trials were selected from 1705 until May 24 on the World Health Organization clinical trials platform related to COVID-19. Jupyter and Python tools were used for data processing and cleaning.

Results

One thousand six hundred seventy-two intervention studies related to SARS-CoV-2 infection were found. China, The United States, Iran, France, and Spain are the countries participating in the largest number of studies, while only 4,1% are from Latin America (mostly Brazilian). 28 studies are focusing only on older adults, and ten studies are based exclusively on populations under 19 years of age.

Conclusion

The worldwide interest in this new disease is reflected in the increasing number of intervention studies that are being carried out to date. How-ever, the studies analyzed do not cover the most vulnerable age groups proportionally and do not have equitable participation of all the coun-tries. In Latin America, this problem is exacerbated by the region's social, economic, and political limitations. Because it is an emerging disease, there is still not enough information to establish strong correlations between the analyzed variables, and the standardization of protocols is not yet definite because most of the studies are in progress.

Duodenum Intestine-Chip for preclinical drug assessment in a human relevant model

Induction of intestinal drug metabolizing enzymes can complicate the development of new drugs, owing to the potential to cause drug-drug interactions (DDIs) leading to changes in pharmacokinetics, safety and efficacy. The development of a human-relevant model of the adult intestine that accurately predicts CYP450 induction could help address this challenge as species differences preclude extrapolation from animals. Here, we combined organoids and Organs-on-Chips technology to create a human Duodenum Intestine-Chip that emulates intestinal tissue architecture and functions, that are relevant for the study of drug transport, metabolism, and DDI. Duodenum Intestine-Chip demonstrates the polarized cell architecture, intestinal barrier function, presence of specialized cell subpopulations, and in vivo relevant expression, localization, and function of major intestinal drug transporters. Notably, in comparison to Caco-2, it displays improved CYP3A4 expression and induction capability. This model could enable improved in vitro to in vivo extrapolation for better predictions of human pharmacokinetics and risk of DDIs.

Commentary: The Problems of Grouping All Adversity Into a Special Populations Label

"Special populations" refer to groups of people whose needs are not fully addressed by traditional health services delivery. Greater access to these services, or tailored services, must be provided to reduce inequities in physical and mental health-care systems. Many different groups have been identified as special populations. We comment on controversies regarding the use of the term special populations in health practice and policy. Applicable conceptual issues include intersectionality, unitization, definitional drawbacks, and looping effects. There is a need to make clear the challenges posed by use of this term (e.g., discrimination, workability). An approach that acknowledges the diversity of groups and accommodates them where necessary without discrimination and unequal treatment is needed.

Chinese herbal medicines for treating gestational diabetes mellitus

This is a protocol for a Cochrane Review (Intervention). The objectives are as follows:

To assess the effectiveness and safety of Chinese herbal medicines for the treatment of women with gestational diabetes mellitus.

Pediatric Trials Run in India: An Analysis of Clinical Trials.gov 2006-2015

OBJECTIVE

To present a snapshot of 10 y of pediatric research, with a focus on trials with at least one enrolling site in India.

METHODS

The study included all interventional trials registered at ClinicalTrials.gov from January 2006 through December 2015, enrolling patients aged 0 to 18 y. The database for Aggregate Analysis of ClinicalTrials.gov (AACT) was the data source used.

RESULTS

Nine thousand, six hundred forty-eight pediatric clinical studies were identified. Of these, 193 had at least one enrolling site in India. The primary purpose for most of these trials was treatment (n = 92) and prevention (n = 65) coupled with an efficacy and/or safety endpoint (n = 158). Infant and toddlers were eligible for enrollment in the majority of trials (97%) while neonates only in 22% of trials. The rate of early termination or withdrawal was 5%. The most commonly studied conditions were bacterial infections, viruses, digestive and mental diseases. Overall, communicable diseases (n = 75) and major non-communicable diseases (n = 72) were equally investigated.

CONCLUSIONS

The most commonly studied therapeutic areas in trials enrolling from India and registered in ClinicalTrials.gov were appropriate for India public health needs and patients were not enrolled into studies inappropriately from this perspective.

Dose adjustment in orphan disease populations: the quest to fulfill the requirements of physiologically based pharmacokinetics

INTRODUCTION

While the media is engaged and fascinated by the idea of 'Precision Medicine', the nuances related to 'Precision Dosing' seem to be largely ignored. Assuming the 'right drug' is selected, clinicians still need to decide on the 'right dose' for individuals. Ideally, optimal dosing should be studied in clinical trials; however, many drugs on the market lack evidence-based dosing recommendations, and small groups of patients (orphan disease populations) are dependent on local guidance and clinician experience to determine drug dosage adjustments. Areas Covered: This report explores the current understanding of dosing adjustment in special populations and examines the requirements for developing 'in silico' models for pediatric, elderly and pregnant patients. The report also highlights current use of modeling to provide evidence-based recommendations for drug labeling in the absence of complete clinical trials in orphan disease populations. Expert Opinion: Physiologically based pharmacokinetics (PBPK) is an attractive prospect for determining the best drug dosage adjustments in special populations. However, it is not sufficient for individualized, or even stratified dosing, unless the systems (drug-independent) data required to build robust PBPK models are obtained. Such models are not a substitute for clinical trials, but they are an alternative to undocumented and inconsistent guesswork.

The emerging role of physiologically based pharmacokinetic modelling in solid drug nanoparticle translation

The use of solid drug nanoparticles (SDN) has become an established approach to improve drug delivery, supporting enhancement of oral absorption and long-acting administration strategies. A broad range of SDNs have been successfully utilised for multiple products and several development programmes are currently underway across different therapeutic areas. With some approaches, a large range of material space is available with diversity in physical characteristics, excipient choice and pharmacological behaviour. The selection of SDN lead candidates is a complex process including a broad range of in vitro and in vivo data, and a better understanding of how physical characteristics relate to performance is required. Physiologically-based pharmacokinetic (PBPK) modelling is based upon a comprehensive integration of experimental data into a mathematical description of drug distribution, allowing simulation of SDN pharmacokinetics that can be qualified in vivo prior to human prediction. This review aims to provide a description of how PBPK can find application into the development of SDN. Integration of predictive PBPK modelling into SDN development allows a better understanding of the SDN dose-response relationship, supporting a framework for rational optimisation while reducing the risk of failure in developing safe and effective nanomedicines.

Orodispersible films: Towards drug delivery in special populations

Orodispersible films (ODF) hold promise as a novel delivery method, with the potential to deliver tailored therapies to different patient populations. This article reviews the current strides of ODF technology and some of its unmet quality and manufacturing aspects. A topic highlights opportunities and limitations of inkjet printed ODF as a population-specific drug delivery. Overall, this article aims to stimulate further research to fill the current knowledge gap between manufacturing and administration requirements of ODF targeting specific patient subpopulations such as geriatrics.

Signal detection activity on EudraVigilance data: analysis of the procedure and findings from an Italian Regional Centre for Pharmacovigilance

BACKGROUND

In July 2012 a new European legislation (Directive 2010/84/EU and Regulation No. 1235/2010) regarding pharmacovigilance has become effective. It has boosted the activity of Signal Detection through a monthly analysis of potential safety signals on EudraVigilance (EV). Our aim is to describe the procedure of signal detection on EV data and to present results obtained by the our pharmacovigilance centre.

METHOD

Data are extracted from EV database, which collects suspected Adverse Drug Reactions (ADRs) of medicinal products in Europe. We are appointed to supervise digoxin, nicardipine, delapril, manidipine and hydrochlorothiazide/ramipril. ADRs are coded through MedDRA Preferred Terms and collected in the electronic Reaction Monitoring Report (eRMR). Statistical analysis is based on the Proportional Reporting Ratio (PRR) as a measure of disproportionality.

RESULTS

Up to April 2016 we have analyzed 45 eRMR for each drug. Two signals for nicardipine were submitted to the Pharmacovigilance Risk Assessment Committee of European Medicines Agency (EMA): acute pulmonary oedema (off-label use as tocolytic) and thrombocytopenia.

CONCLUSIONS

Our experience shows the scientific and regulatory value of signal detection activity on EV data in order to continuously evaluate the benefit/risk profile of recent and older drugs.

Design and conduct of early phase drug studies in children: challenges and opportunities

It has historically been very difficult to conduct early phase drug studies in children for a number of reasons related to ethics, acceptability, rarity, standardization, end points, safety, dosing and feasibility. Over the past decade there have been a number of developments including novel clinical trial design, in silico pharmacology and microdosing that have significantly enhanced the ability of investigators to conduct early phase drug studies in children. While the evolution of drug therapy is creating a series of new challenges, there has never been a better time for conducting drug studies in children.