Clinical Evaluation Considerations for Pediatric Drugs Evaluated with Adults in Japan

1. Background

The development of pediatric dosages often lags due to challenges in clinical trials and small market size, leading to unapproved uses. Some drugs have approved dosages for pediatric patients 12 years and older matching adults. Information on pediatric use is limited, especially for diseases with fewer pediatric patients, and age categorizations vary across drugs. Globally, ICH guidelines address pediatric clinical studies, including planning, study types, and age categorizations. The U.S. FDA guidance allows including adolescents in adult oncology trials for similar malignancies. https://www.pmda.go.jp/files/000238732.pdf

2. Policy Intent

To streamline and optimize clinical development for pediatric drugs by outlining age groups and diseases where pediatric patients (10 or 12 years and older) can be evaluated together with adults, provided pathology is similar and dosage/formulation matches. This represents general principles, not mandatory for all drugs, and should not delay adult trials. https://www.pmda.go.jp/files/000238732.pdf

3. Target Products

Drugs for diseases where pathology in target pediatric age group is similar to adults, or regarded as similar for clinical evaluation. Includes type 2 diabetes mellitus, familial hypercholesterolemia, allergic diseases (bronchial asthma, allergic rhinitis), antimicrobials/antivirals, and hematopoietic malignancy. Efficacy endpoints must be applicable to both populations. https://www.pmda.go.jp/files/000238732.pdf

4. Eligibility Types

• Age Group: In principle, 10 or 12 years and older, where drug exposure, dosage (same as adults or within range), and formulation match adults. Based on similar drug-metabolizing enzymes, transporters, and renal function in this age group. Specific ages determined by disease and drug characteristics; inclusion of younger children possible if justified (e.g., safety margin). https://www.pmda.go.jp/files/000238732.pdf
• Patient Considerations: Exclude markedly short stature/low body weight for safety; consider impacts on growth/development in long-term studies; obtain informed assent. https://www.pmda.go.jp/files/000238732.pdf

5. Consultation Pathways

Marketing Authorization Holders must be informed by Prefectural Health Departments. Development rationale explained before studies and at marketing application. Collaboration with academic societies for proper use and safety data collection post-approval. https://www.pmda.go.jp/files/000238732.pdf

6. Approval Processes

• Applies to confirmatory/long-term studies after adult dosage established in exploratory studies. https://www.pmda.go.jp/files/000238732.pdf
• Include pediatric patients in adult studies if dosage matches; collect pharmacokinetics, efficacy, safety data. https://www.pmda.go.jp/files/000238732.pdf
• No mandatory subgroup analysis for pediatrics if etiology/dosage similar; useful for data collection. https://www.pmda.go.jp/files/000238732.pdf
• Ethical requirements per ICH guidelines: protect rights, minimize risks, obtain assent. https://www.pmda.go.jp/files/000238732.pdf
• For individual drugs: Assess nonclinical juvenile animal studies if data insufficient; explain dosage appropriateness via pharmacokinetics/PK/PD/exposure-response (e.g., simulations); consider body height/weight limits for special populations. https://www.pmda.go.jp/files/000238732.pdf

7. Post-Approval Obligations

• For limited pre-marketing pediatric data: Collect additional information shortly after launch, focusing on safety; provide to professionals; consider limited initial use in select institutions. https://www.pmda.go.jp/files/000238732.pdf
• For sufficient pre-marketing data: As-needed collection; active collaboration with societies for use and safety monitoring. https://www.pmda.go.jp/files/000238732.pdf
• Label limited information at approval; promptly update with post-marketing data. https://www.pmda.go.jp/files/000238732.pdf
• For hematopoietic malignancies: Step-by-step expansion if limited data; ongoing exploration for better dosages. https://www.pmda.go.jp/files/000238732.pdf

8. Practical Considerations

• Safety measures: Hypoglycemia frequency higher in pediatrics due to variability; avoid oral steroids in children for allergic rhinitis; prevent resistant bacteria/viruses. https://www.pmda.go.jp/files/000238732.pdf
• Disease-Specific: For T2DM, target 10+ years; monitor growth for GLP-1/SGLT2 drugs. For FH, target 10+ years; consider pubertal stages. For asthma/rhinitis, target 12+ years; assess self-assessment feasibility. For infections, target 12+ years; consider global development. For malignancies, target 12+ years; justify younger inclusion if mechanism clear. https://www.pmda.go.jp/files/000238732.pdf
• Not extrapolation-based but combined evaluation where similar. https://www.pmda.go.jp/files/000238732.pdf

9. Effective Date

Administrative Notice dated June 30, 2020; provisional translation as of January 2021. https://www.pmda.go.jp/files/000238732.pdf