Combined Pediatric and Adult Trials Submitted to the US Food and Drug Administration 2012-2018

How the French national authority for health assesses medicines for use in pediatrics

Children deserve to be treated with appropriate medicines based on robust assessments. Despite the introduction of new regulations, the availability of medicines for children is suboptimal because of the frequent lack of relevant clinical trials due to the difficulty of conducting such trials. Thus, the Transparency Committee (TC) of the French National Authority for Health, who oversees the assessment of medicinal products in France, set up a pediatric working group with two aims: (1) The first aim was to review all opinions on medicines for pediatric use. Out of 536 opinions delivered between 2020 and 2022, 181 (34 %) concerned medicines for pediatric use. Whereas oncology largely dominated the medicines for adults, medicines for infectious diseases, endocrinology/metabolism, neurology, and hematology mostly prevailed for children. (2) The second aim was to clarify the evaluation criteria assessed by the TC, namely, the clinical benefit (CB), the clinical added value (CAV), and the public health impact (PHI) for pediatric medicinal products. An important CB was given to 113 out of 161 (71 %) opinions on medicines for pediatric use when it concerned pathologies with a severe prognosis. The quality of the demonstration (e.g., double-blind randomized trial vs. placebo or another active medicine) played a major role in the CB level. Clinical pediatric studies were also consistently associated with higher CAV levels: levels I (major) to III (moderate) in 26 out of 42 (62 %) opinions, level IV (minor) and level V (no therapeutic progress) in 43 out of 84 (51 %) and 30 out of 43 (70 %) opinions granting a sufficient CB, respectively. Conversely, 22 out of 30 (73 %) dossiers based only on literature reviews were given a level V. The main criteria leading to the qualification of a medicine for pediatric use as providing a PHI included a significant change in the morbidity and mortality of the disease and an improvement in the care pathway. Assessments were mostly aligned on the adults in the case of subsequent extensions of indications to children. Lastly, new measures were taken aimed at shortening median delays in the assessment process in order to reduce off-label use of medicines in France.

Achievement of therapeutic antibiotic exposures using Bayesian dosing software in critically unwell children and adults with sepsis

PURPOSE

Early recognition and effective treatment of sepsis improves outcomes in critically ill patients. However, antibiotic exposures are frequently suboptimal in the intensive care unit (ICU) setting. We describe the feasibility of the Bayesian dosing software Individually Designed Optimum Dosing Strategies (ID-ODS™), to reduce time to effective antibiotic exposure in children and adults with sepsis in ICU.

METHODS

A multi-centre prospective, non-randomised interventional trial in three adult ICUs and one paediatric ICU. In a pre-intervention Phase 1, we measured the time to target antibiotic exposure in participants. In Phase 2, antibiotic dosing recommendations were made using ID-ODS™, and time to target antibiotic concentrations were compared to patients in Phase 1 (a pre-post-design).

RESULTS

175 antibiotic courses (Phase 1 = 123, Phase 2 = 52) were analysed from 156 participants. Across all patients, there was no difference in the time to achieve target exposures (8.7 h vs 14.3 h in Phase 1 and Phase 2, respectively, p = 0.45). Sixty-one courses in 54 participants failed to achieve target exposures within 24 h of antibiotic commencement (n = 36 in Phase 1, n = 18 in Phase 2). In these participants, ID-ODS™ was associated with a reduction in time to target antibiotic exposure (96 vs 36.4 h in Phase 1 and Phase 2, respectively, p < 0.01). These patients were less likely to exhibit subtherapeutic antibiotic exposures at 96 h (hazard ratio (HR) 0.02, 95% confidence interval (CI) 0.01-0.05, p < 0.01). There was no difference observed in in-hospital mortality.

CONCLUSIONS

Dosing software may reduce the time to achieve target antibiotic exposures. It should be evaluated further in trials to establish its impact on clinical outcomes.

Assessment of Dosing Strategies for Pediatric Drug Products

Pediatric drug dosing is challenged by the heterogeneity of developing physiology and ethical considerations surrounding a vulnerable population. Often, pediatric drug dosing leverages findings from the adult population; however, recent regulatory efforts have motivated drug sponsors to pursue pediatric-specific programs to meet an unmet medical need and improve pediatric drug labeling. This paradigm is further complicated by the pathophysiological implications of obesity on drug distribution and metabolism and the roles that body composition and body size play in drug dosing. Therefore, we sought to understand the landscape of pediatric drug dosing by characterizing the dosing strategies from drug products recently approved for pediatric indications identified using FDA Drug Databases and analyze the impact of body size descriptors (age, body surface area, weight) on drug pharmacokinetics for several selected antipsychotics approved in pediatric patients. Our review of these pediatric databases revealed a dependence on body size-guided dosing, with 68% of dosing in pediatric drug labelings being dependent on knowing either the age, body surface area, or weight of the patient to guide dosing for pediatric patients. This dependence on body size-guided dosing drives the need for special consideration when dosing a drug in overweight and obese patients. Exploratory pharmacokinetic analyses in antipsychotics illustrate possible effects of drug exposure when applying different dosing strategies for this class of drugs. Future efforts should aim to further understand the pediatric drug dosing and obesity paradigm across pediatric age ranges and drug classes to optimize drug development and clinical care for this patient population.

Clinical trial considerations for pediatric cancer drug development

Oncology has been one of the most active therapeutic areas in medicinal products development. Despite this fact, few drugs have been approved for use in pediatric cancer patients when compared to the number approved for adults with cancer. This disparity could be attributed to the fact that many oncology drugs have had orphan drug designation and were exempt from Pediatric Research Equity Act (PREA) requirements. On August 18, 2017, the RACE for Children Act, i.e. Research to Accelerate Cures and Equity Act, was signed into law as Title V of the 2017 FDA Reauthorization Act (FDARA) to amend the PREA. Pediatric investigation is now required if the drug or biological product is intended for the treatment of an adult cancer and directed at a molecular target that FDA determines to be "substantially relevant to the growth or progression of a pediatric cancer." This paper discusses the specific considerations in clinical trial designs and statistical methodologies to be implemented in oncology pediatric clinical programs.

Pediatric Drug Development: Reviewing Challenges and Opportunities by Tracking Innovative Therapies

The paradigm of pediatric drug development has been evolving in a "carrot-and-stick"-based tactic to address population-specific issues. However, the off-label prescription of adult medicines to pediatric patients remains a feature of clinical practice, which may compromise the age-appropriate evaluation of treatments. Therefore, the United States and the European Pediatric Formulation Initiative have recommended applying nanotechnology-based delivery systems to tackle some of these challenges, particularly applying inorganic, polymeric, and lipid-based nanoparticles. Connected with these, advanced therapy medicinal products (ATMPs) have also been highlighted, with optimistic perspectives for the pediatric population. Despite the results achieved using these innovative therapies, a workforce that congregates pediatric patients and/or caregivers, healthcare stakeholders, drug developers, and physicians continues to be of utmost relevance to promote standardized guidelines for pediatric drug development, enabling a fast lab-to-clinical translation. Therefore, taking into consideration the significance of this topic, this work aims to compile the current landscape of pediatric drug development by (1) outlining the historic regulatory panorama, (2) summarizing the challenges in the development of pediatric drug formulation, and (3) delineating the advantages/disadvantages of using innovative approaches, such as nanomedicines and ATMPs in pediatrics. Moreover, some attention will be given to the role of pharmaceutical technologists and developers in conceiving pediatric medicines.

Elbasvir/grazoprevir in children aged 3-18 years with chronic HCV genotype 1 or 4 infection: a pharmacokinetic modeling study

BACKGROUND

Approximately 3.5 million children and adolescents worldwide are chronically infected with HCV. This study uses pharmacokinetic modeling to identify pediatric doses of elbasvir/grazoprevir (EBR/GZR) that achieve plasma concentrations similar to those seen in adults receiving the approved fixed-dose combination regimen of EBR/GZR.

PATIENTS AND METHODS

We conducted a nonrandomized, single-arm, multicenter, open-label phase 2b trial in children and adolescents aged 3 to <18 years with chronic HCV genotype 1 or 4 infection (NCT03379506). Pharmacokinetic data were used to bridge efficacy and safety data from adults to children in a stepwise (oldest to youngest) manner. A total of 57 participants were enrolled: cohort 1 (aged 12 to <18 y), n=22; cohort 2 (aged 7 to <12 y), n=17; and cohort 3 (aged 3 to <7 y), n=18.

RESULTS

Steady-state plasma exposures were achieved by week 4 for EBR and GZR in all cohorts and daily dosing achieved geometric mean steady-state area under the concentration-time curve at 0-24 hours that fell within comparability bounds established for adults. All participants achieved sustained virologic response 12 weeks after completing treatment (ie, undetectable HCV RNA 12 wk following completion of treatment). Headache (n=4), fatigue (n=4), and nausea (n=2) were the most common treatment-related adverse events (all mild or moderate); no participant discontinued because of an adverse event.

CONCLUSIONS

Pediatric EBR/GZR pharmacokinetic models were successfully developed based on complex adult population pharmacokinetic models. At appropriate age-related doses, EBR/GZR is safe and effective in pediatric and adolescent participants with HCV infection.

Denials, Dilly-dallying, and Despair: Navigating the Insurance Labyrinth to Obtain Medically Necessary Medications for Pediatric Inflammatory Bowel Disease Patients

Increasingly, in the United States, the prescribing of high-cost drugs has become a challenge for physicians and other practitioners. Such drugs are highly regulated by third-party payers (aka insurance), as well as pharmacy benefit managers. Not infrequently, a clinician prescribing a medication will have the payment for the prescription denied by the third-party payer, with the end result being a delay in getting a medically necessary medication to a patient. This article highlights the challenges involved in the prior authorization and denial process, with a focus on pediatric inflammatory bowel disease. The article reviews the role of pharmacy benefits managers in restricting access to drugs, and the reasons why denials of medically necessary medications may occur. The article also provides information on how to appeal denials, how to write a letters of medical necessity, and how to conduct a proper peer-to-peer review. Advocacy from patients and clinicians will be important, as we want to reform the process in the future.

Accelerating the Availability of Medications to Pediatric Patients by Optimizing the Use of Extrapolation of Efficacy

Improving pediatric therapeutic development is a mission of universal importance among health authorities, pharmaceutical companies, academic institutions, and healthcare professionals. Following the passage of legislation in the United States and Europe, we witnessed the most significant advancement yet in pediatric data generation, resulting in added pediatric use information to almost 700 product labels. Tools to accelerate generation of data for the pediatric population are available for use today, and when utilized in accordance with current practices and laws, these tools could increase the amount and timeliness of pediatric information available for clinicians and patients. If we utilize the current laws that allow regulators to incentivize and require evidence generation, apply extrapolation, and utilize modeling and simulation, as well as including adolescents in the pivotal studies alongside adults as appropriate, two strategic goals could be achieved by 2030: (1) reduce the time to pediatric approval by 50%, and (2) renew pediatric labeling information for 15 priority pediatric drugs without patent and/or exclusivity.

Pediatric and Adult Placebo Response Rates in Placebo-Controlled Clinical Trials Submitted to the US FDA 2012-2020

The use of placebo concurrent control (placebo-controlled) is the most rigorous method of evaluating the safety and efficacy of investigational treatments. However, the use of a placebo group in pediatric product development can be challenging due to ethical considerations and potential differences in placebo response rates between adults and children. This study reports the US Food and Drug Administration's experience with placebo response rates in the pediatric population. Products studied under the Best Pharmaceuticals for Children Act and the Pediatric Research Equity Act between 2012 and 2020 were screened. Study characteristics including study type, primary efficacy endpoint(s), placebo response rates for the primary efficacy endpoint(s) and studied age range were collected. A total of 71 drug products used a placebo-controlled trial. Of these, thirteen products had an identical study design and trial characteristics including the primary efficacy endpoints between pediatric and adult studies. Fifteen products were studied in trials with identical study design but only different primary efficacy endpoints in pediatric and adult populations. Ten products had combined adolescent and adult trials with separate pediatric trials in younger age groups. In each of these cases, the pediatric placebo response was greater, for some trials, and less, for other trials, than the adult placebo response. The pediatric placebo response can vary within an age group for a drug product. Future studies should examine the factors leading to a similarity or dissimilarity in placebo response between pediatric patients and adults. This article is protected by copyright. All rights reserved.

Pediatric Drug Development Studies for Familial Hypercholesterolemia Submitted to the US Food and Drug Administration Between 2007 and 2020

Familial hypercholesterolemia (FH) is an autosomal dominant genetic disorder of lipoprotein metabolism that leads to an increased risk of developing atherosclerosis and coronary artery disease. Hypercholesterolemia in pediatric patients is typically due to FH. Treatment of pediatric FH is achieved through lifestyle modifications, lipid-modifying pharmacotherapy, and/or apheresis. The primary objective of this review is to describe the characteristics of clinical trials conducted in pediatric patients with FH with data submitted to the US Food and Drug Administration from 2007 to 2020. Of 10 trials with 8 products in pediatric FH submitted to the Food and Drug Administration, 1 product was studied in both the heterozygous and the homozygous phenotypes, 5 were studied for heterozygous hypercholesterolemia only, and 2 were studied for homozygous familial hypercholesterolemia only. Most of the trials included pediatric patients ≥10 years of age and older. Clinical trial characteristics including the primary efficacy end points between pediatric and adult trials were mostly identical. Many lipid-lowering drugs with novel mechanisms of action have been recently approved or are currently being studied. In summary, the drug treatment of hypercholesterolemia in pediatric patients is expanding beyond the use of statins, and now involves multiple mechanisms of action involving cholesterol metabolism. As younger pediatric patients are diagnosed and treated for heterozygous familial hypercholesterolemia and homozygous familial hypercholesterolemia, optimizing the doses of these agents and safety studies specific to younger pediatric patients will be necessary.

The Revolution in Pediatric Drug Development and Drug Use: Therapeutic Orphans No More

This lecture was given by Dr. Burckart in association with presentation of the 2014 Sumner J. Yaffe Lifetime Achievement Award in Pediatric Pharmacology and Therapeutics, which is selected by the Pediatric Pharmacy Association. Multiple factors make conducting drug studies in the pediatric population difficult, resulting in a historic lack of information surrounding safe and efficacious drug dosing in children. The paradigm in pediatric drug development has shifted from normal science being that children are therapeutic orphans in the drug development system, to a model drift caused by pediatric legislation, to a model crisis caused by failed pediatric drug development trials, to finally a model revolution that includes pediatric patients routinely in drug development. Major regulatory actions and the accumulation of scientific evidence has created an environment where clinicians can expect properly labeled drug usage information for the pediatric population.