Real-World Evidence for Assessing Treatment Effectiveness and Safety in Pediatric Populations

Validation of new medication use algorithms as proxies for worsening disease activity in patients with juvenile idiopathic arthritis

PURPOSE

To facilitate claims-based research on populations with juvenile idiopathic arthritis (JIA), we sought to validate an algorithm of new medication use as a proxy for worsening JIA disease activity.

METHODS

Using electronic health record data from three pediatric centers, we defined new JIA medication use as (re)initiation of disease-modifying antirheumatic drugs or glucocorticoids (oral or intra-articular). Data were collected from 201 randomly selected subjects with (101) or without (100) new medication use. We assessed the positive predictive value (PPV) and negative predictive value (NPV) based on a reference standard of documented worsening of JIA disease activity. The algorithm was refined to optimize test characteristics.

RESULTS

Overall, the medication-based algorithm had suboptimal performance in representing worsening JIA disease activity (PPV 69.3%, NPV 77.1%). However, algorithm performance improved for definitions specifying longer times after JIA diagnosis (≥1-year post-diagnosis: PPV 82.9%, NPV 80.0%) or after initiation of prior JIA treatment (≥1-year post-treatment: PPV 89.7%, NPV 80.0%).

CONCLUSION

An algorithm for new JIA medication use appears to be a reasonable proxy for worsening JIA disease activity, particularly when specifying new use ≥1 year since initiating a prior JIA medication. This algorithm will be valuable for conducting research on JIA populations within administrative claims databases.

Stimulant Patterns, Alone or with Other Psychotropic Classes, in Medicaid-Insured Youth Continuously Enrolled for 3-8 Years

Objective: Little U.S. pharmacoepidemiologic study is based on treatment during continuous enrollment for periods more than a year. This study aims to show pediatric patterns of stimulant use (alone or with other psychotropic classes) from Medicaid administrative claims data for stimulant patterns of 3- to 8-year continuous enrollees. Methods: A retrospective cohort study was derived from Medicaid enrollment, pharmacy, and diagnosis claims data (2007-2014) in a mid-Atlantic state. Youth aged 2-17 years with 3-8 years of continuous enrollment treated with stimulants were compared with a date-matched comparison group treated without stimulants. Major outcomes include prevalence and duration of stimulant use and patterns of stimulant polypharmacy across relatively long enrollments (3-8 years). Results: Among 264,518 unique 2- to 17-year olds with 3-8 years of continuous enrollment, 16.5% had stimulant prescription dispensings, doubling the annual national prevalence of 8.1%. Subgroup analysis showed that the highest prevalence of stimulant use was for 6- to 11-year olds (20.4%), foster care eligible youth (42.3%), and those with 7-8 years of continuous enrollment (20.1%). Externalizing psychiatric disorders were far more common in those treated with stimulants than in those treated without stimulants. The duration of stimulant exposure overall was a median of 487 days, half that of foster care stimulant users. Stimulant polypharmacy with two or more psychotropic classes concomitantly characterized 29.8% of stimulant users. Among those with three or four or more class polypharmacy, 85% and 88%, respectively, had concomitant stimulant and antipsychotic use. The adjusted odds ratio (AOR) of three or more class polypharmacy significantly increased in 12- to 17-year-old age group (AOR = 1.8), foster care eligibility (AOR = 4.5), and among those with the longest enrollment (AOR = 1.7). Conclusions and Relevance: Stimulant prevalence in Medicaid-insured youth with continuous enrollment of 3-8 years was twice as common as in annual data sets. Future research should investigate three to five interclass stimulant polypharmacy effectiveness in reliably diagnosed community populations.

Pediatric oncology drug development and dosage optimization

Oncology drug discovery and development has always been an area facing many challenges. Phase 1 oncology studies are typically small, open-label, sequential studies enrolling a small sample of adult patients (i.e., 3-6 patients/cohort) in dose escalation. Pediatric evaluations typically lag behind the adult development program. The pediatric starting dose is traditionally referenced on the recommended phase 2 dose in adults with the incorporation of body size scaling. The size of the study is also small and dependent upon the prevalence of the disease in the pediatric population. Similar to adult development, the dose is escalated or de-escalated until reaching the maximum tolerated dose (MTD) that also provides desired biological activities or efficacy. The escalation steps and identification of MTD are often rule-based and do not incorporate all the available information, such as pharmacokinetic (PK), pharmacodynamic (PD), tolerability and efficacy data. Therefore, it is doubtful if the MTD approach is optimal to determine the dosage. Hence, it is important to evaluate whether there is an optimal dosage below the MTD, especially considering the emerging complexity of combination therapies and the long-term tolerability and safety of the treatments. Identification of an optimal dosage is also vital not only for adult patients but for pediatric populations as well. Dosage-finding is much more challenging for pediatric populations due to the limited patient population and differences among the pediatric age range in terms of maturation and ontogeny that could impact PK. Many sponsors defer the pediatric strategy as they are often perplexed by the challenges presented by pediatric oncology drug development (model of action relevancy to pediatric population, budget, timeline and regulatory requirements). This leads to a limited number of approved drugs for pediatric oncology patients. This review article provides the current regulatory landscape, incentives and how they impact pediatric drug discovery and development. We also consider different pediatric cancers and potential clinical trial challenges/opportunities when designing pediatric clinical trials. An outline of how quantitative methods such as pharmacometrics/modelling & simulation can support the dosage-finding and justification is also included. Finally, we provide some reflections that we consider helpful to accelerate pediatric drug discovery and development.

Creating a Medication Therapy Observational Research Database from an Electronic Medical Record: Challenges and Data Curation

BACKGROUND

Observational research has shown its potential to complement experimental research and clinical trials by secondary use of treatment data from hospital care processes. It can also be applied to better understand pediatric drug utilization for establishing safer drug therapy. Clinical documentation processes often limit data quality in pediatric medical records requiring data curation steps, which are mostly underestimated.

OBJECTIVES

The objectives of this study were to transform and curate data from a departmental electronic medical record into an observational research database. We particularly aim at identifying data quality problems, illustrating reasons for such problems and describing the systematic data curation process established to create high-quality data for observational research.

METHODS

Data were extracted from an electronic medical record used by four wards of a German university children's hospital from April 2012 to June 2020. A four-step data preparation, mapping, and curation process was established. Data quality of the generated dataset was firstly assessed following an established 3 × 3 Data Quality Assessment guideline and secondly by comparing a sample subset of the database with an existing gold standard.

RESULTS

The generated dataset consists of 770,158 medication dispensations associated with 89,955 different drug exposures from 21,285 clinical encounters. A total of 6,840 different narrative drug therapy descriptions were mapped to 1,139 standard terms for drug exposures. Regarding the quality criterion correctness, the database was consistent and had overall a high agreement with our gold standard.

CONCLUSION

Despite large amounts of freetext descriptions and contextual knowledge implicitly included in the electronic medical record, we were able to identify relevant data quality issues and to establish a semi-automated data curation process leading to a high-quality observational research database. Because of inconsistent dosage information in the original documentation this database is limited to a drug utilization database without detailed dosage information.

Safety of Intravenous Pantoprazole Sodium in Pediatric Patients Aged 1 Month to < 1 Year: A Real-World Retrospective Cohort Study

OBJECTIVE

To estimate the incidence rates (IR) of prespecified outcomes of interest in pediatric patients (1 month to < 1 year) treated with intravenous (IV) pantoprazole using Optum's longitudinal electronic health records database (Optum Market Clarity) from the United States (US).

METHODS

This real-world, non-interventional, retrospective cohort study was conducted from 01 January 2007 to 31 December 2020 in patients who received IV pantoprazole. Premature patients and those weighing < 2.36 kg were excluded. Patients were categorized based on diagnosis of gastroesophageal reflux disease (GERD) and erosive esophagitis (EE) into: Subgroup 1 (GERD and EE), Subgroup 2 (GERD and no EE), and Subgroup 3 (absence of GERD and EE). Overall IRs (per 1000 person-years [PY]) and 95% confidence intervals (CI) of outcomes were estimated (overall and subgroups) and stratified by duration of IV pantoprazole treatment (< 4 days versus ≥ 4 days).

RESULTS

Of 1879 eligible patients, none were identified in Subgroup 1; 851 (45.3%) and 1028 (54.7%) patients were identified in Subgroups 2 and 3, respectively. IRs of outcomes of interest ranged from 0.0 to 742.8 per 1000 PY. IRs were highest for vomiting (742.80), diarrhea (377.77), abdominal distension (214.31), hyponatremia (204.99), and hypokalemia (203.49). IRs were comparable between Subgroups 2 and 3. For most outcomes, IRs were higher among patients treated with IV pantoprazole for ≥ 4 days versus those treated for < 4 days.

CONCLUSION

These results are consistent with the known safety profile of pantoprazole and emphasize the utility of using real-world data from pediatric populations for assessment of safety outcomes.

Overview of global real-world data sources for pediatric pharmacoepidemiologic research

PURPOSE

Given limited information available on real-world data (RWD) sources with pediatric populations, this study describes features of globally available RWD sources for pediatric pharmacoepidemiologic research.

METHODS

An online questionnaire about pediatric RWD sources and their attributes and capabilities was completed by members and affiliates of the International Society for Pharmacoepidemiology and representatives of nominated databases. All responses were verified by database representatives and summarized.

RESULTS

Of 93 RWD sources identified, 55 unique pediatric RWD sources were verified, including data from Europe (47%), United States (38%), multiregion (7%), Asia-Pacific (5%), and South America (2%). Most databases had nationwide coverage (82%), contained electronic health/medical records (47%) and/or administrative claims data (42%) and were linkable to other databases (65%). Most (71%) had limited outside access (e.g., by approval or through local collaborators); only 10 (18%) databases were publicly available. Six databases (11%) reported having >20 million pediatric observations. Most (91%) included children of all ages (birth until 18th birthday) and contained outpatient medication data (93%), while half (49%) contained inpatient medication data. Many databases captured vaccine information for children (71%), and one-third had regularly updated data on pediatric height (31%) and weight (33%). Other pediatric data attributes captured include diagnoses and comorbidities (89%), lab results (58%), vital signs (55%), devices (55%), imaging results (42%), narrative patient histories (35%), and genetic/biomarker data (22%).

CONCLUSIONS

This study provides an overview with key details about diverse databases that allow researchers to identify fit-for-purpose RWD sources suitable for pediatric pharmacoepidemiologic research.

Real world data (RWD) in pediatrics

Unique challenges pertain when studying children, although many research principles are the same as those when studying adult populations. This truism extends to the use of real-world data (RWD). RWD are particularly relevant to pediatrics because they may potentially provide an additional source of data to inform pediatric labeling and practice patterns when clinical trials have not been or cannot be conducted. The purpose of this commentary is to provide a brief overview of the unique issues in using RWD to study the effectiveness or safety of medical therapies in children.

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.

The Role of Real-World Data and Evidence in Oncology Medicines Approved in EU in 2018-2019

Use of Real-World data (RWD) has gained the interest of different stakeholders in cancer care. The aim of this study was to identify and describe the use of RWD/RWE during the pre-authorisation phase of products authorised by the EMA in 2018 and 2019 (n=111), with the focus on oncology medicines (n=24). Information was extracted from the European Public Assessment Report (EPAR) summaries and recorded for 5 stages (11 categories) of the drug development lifecycle (discovery, early development, clinical development, registration/market launch, lifecycle management). Specific chapters of full EPAR were reviewed to substantiate the findings on RWD/RWE use in clinical trial design, efficacy, safety, and effectiveness evaluation. RWD/RWE is present in all stages of the oncology drug development; 100.0% in discovery, 37.5% early development, 58.3% in clinical development, 62.5% in registration decision and 100.0% in post-authorization lifecycle management. Examples showed that trial design supported by RWD/RWE included use of open label/single arm studies; efficacy was about using either comparison of results to historical controls, supplying survey data obtained outside the clinical trial or utilizing expert panel advice; safety about including literature findings in evidence; and effectiveness on comparison of trial results of the given product to historical data or existing standard of care. The findings of this study provide specific insights into how RWD/RWE is used in development of cancer therapeutics, how it contributes to regulatory decision making and can guide further policy developments in this field.

Landscape analysis for a neonatal disease progression model of bronchopulmonary dysplasia: Leveraging clinical trial experience and real-world data

The 21^st Century Cures Act requires FDA to expand its use of real-world evidence (RWE) to support approval of previously approved drugs for new disease indications and post-marketing study requirements. To address this need in neonates, the FDA and the Critical Path Institute (C-Path) established the International Neonatal Consortium (INC) to advance regulatory science and expedite neonatal drug development. FDA recently provided funding for INC to generate RWE to support regulatory decision making in neonatal drug development. One study is focused on developing a validated definition of bronchopulmonary dysplasia (BPD) in neonates. BPD is difficult to diagnose with diverse disease trajectories and few viable treatment options. Despite intense research efforts, limited understanding of the underlying disease pathobiology and disease projection continues in the context of a computable phenotype. It will be important to determine if: 1) a large, multisource aggregation of real-world data (RWD) will allow identification of validated risk factors and surrogate endpoints for BPD, and 2) the inclusion of these simulations will identify risk factors and surrogate endpoints for studies to prevent or treat BPD and its related long-term complications. The overall goal is to develop qualified, fit-for-purpose disease progression models which facilitate credible trial simulations while quantitatively capturing mechanistic relationships relevant for disease progression and the development of future treatments. The extent to which neonatal RWD can inform these models is unknown and its appropriateness cannot be guaranteed. A component of this approach is the critical evaluation of the various RWD sources for context-of use (COU)-driven models. The present manuscript defines a landscape of the data including targeted literature searches and solicitation of neonatal RWD sources from international stakeholders; analysis plans to develop a family of models of BPD in neonates, leveraging previous clinical trial experience and real-world patient data is also described.