The U.S. Food and Drug Administration (FDA) Oncology Center of Excellence, Center for Drug Evaluation and Research, and Center for Biologics Evaluation and Research released multiple draft guidances related to Cancer Clinical Trial Eligibility Criteria(s) last Thursday (25 March 2024).
A clinical trial’s eligibility criteria (for inclusion and exclusion) are essential components of the trial, defining the characteristics of the study population.
The purpose of eligibility criteria for cancer clinical trials is to select the intended patient population and reduce potential risks to trial participants. Although eligibility criteria are sometimes too restrictive, expanding them to be more inclusive may increase the diversity of clinical trial populations.
In particular, this guidance provides recommendations on the appropriate use of washout periods and the exclusion of concomitant medications.
A washout period is a treatment-free period between the most recent anti-cancer treatment and treatment with the investigational drug. This treatment-free period is intended to allow a prior therapy and/or its effects on the body to be eliminated or reduced to acceptable levels preventing additional toxicity when a new therapy is started.
Specifically, this guidance includes recommendations regarding the appropriate use of washout periods and concomitant medication exclusions.
Performance status (PS), a measure of how well a patient is able to perform ordinary tasks and carry out activities of daily living, is one of the most common eligibility criteria in oncology trials. Many trials are limited to high-functioning participants (i.e., “good” PS) and exclude lower-functioning patients (i.e., “poor” PS) based on one of two main scales: Eastern Cooperative Oncology Group (ECOG) and Karnofsky (KPS).
Specifically, this guidance includes recommendations regarding expanding eligibility criteria to include patients with a wider range of performance status.
Laboratory value-based eligibility criteria are one of the most common categories of eligibility criteria in clinical trials. Laboratory values within a range demonstrating that organs are functioning above a minimum acceptable level are often required for drugs that pose toxicity risks to specific organ systems or are metabolized and cleared by that organ system(s).
Specifically, this guidance includes recommendations for selecting appropriate laboratory values as trial eligibility criteria to avoid unjustified exclusions of diverse trial participants.
The purpose of these guidances is to assist stakeholders, such as sponsors and/or institutional review boards, that are responsible for clinical trials development and oversight.