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Human Absorption, Metabolism, and Excretion (hAME) Mass Balance Studies in Patients With Cancer
Begoña de Las Heras1,2,3, Claudine Oelke3, Pamela Atwell3
1Oncology Consultants, Madrid, Spain.
Clinical and Translational Science
|May 29, 2026
Summary
Radiolabeled mass balance studies in cancer patients (CPs) are crucial for drug development when healthy volunteers (HVs) are unsuitable. This guide details key considerations for successfully conducting these vital absorption, metabolism, and excretion (AME) studies in CPs.
Area of Science:
- Clinical Pharmacology
- Drug Development
- Radiopharmaceutical Science
Background:
- Radiolabeled mass balance studies are essential for understanding drug absorption, metabolism, and excretion (AME).
- These studies typically involve healthy volunteers (HVs).
- Certain drug characteristics or toxicity may preclude the use of HVs, necessitating the enrollment of cancer patients (CPs).
Purpose of the Study:
- To provide an overview of critical aspects for conducting radiolabeled mass balance studies in cancer patients (CPs).
- To highlight the unique challenges and considerations when using CPs instead of HVs.
- To ensure successful execution of AME studies in a patient population.
Main Methods:
- Review of essential factors for AME studies in CPs.
- Consideration of pharmacologic properties and dose administration.
- Addressing patient clinical status, comorbidities, and study logistics.
Main Results:
- Successful conduct of AME studies in CPs requires careful management of specific factors.
- Key considerations include patient selection, dose management, clinical status, confinement, and study extension.
- Training and hospital requirements are also crucial for successful study delivery.
Conclusions:
- Conducting radiolabeled mass balance studies in cancer patients is feasible and necessary in certain drug development scenarios.
- Proactive planning and management of patient-specific and logistical factors are essential for study success.
- These studies provide critical human AME data for investigational drugs.
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