A year and a half after US Food and Drug Administration (FDA) officials called for including adolescent patients in adult oncology clinical trials, the agency has issued draft guidance providing recommendations to industry on how to do so.
The draft guidance, which addresses many of issues laid out in a 2016 article in Clinical Cancer Research, says that adolescent patients, ages 12 to 17, “should be eligible for enrollment in adult oncology clinical trials at all stages of drug development” when the cancer being studied or the molecular target of the drug under investigation is the same in both adults and adolescents.
“Adolescents, because of their age, generally are not eligible for enrollment in adult oncology trials, and the initial pediatric trials for many drugs are conducted years later, often after the drug is approved in adults,” FDA writes.
This, FDA says, leads to delayed access to potentially effective treatments for adolescent patients and makes enrolling adolescent patients in pediatric trials after approval more difficult as many adolescent patients will be given the treatment off-label rather than wait to participate in a study.
Specifically, the guidance provides recommendations for the appropriate inclusion criteria; dosing and pharmacokinetic (PK) evaluations; safety monitoring; and ethical requirements for enrolling adolescent patients in adult oncology trials.
While FDA says that adolescents should be eligible for studies at all stages of development, the agency does make specific recommendations for adolescent inclusion in early stage trials.
FDA says that adolescents should only be enrolled in first-in-human or dose-escalation trials after initial adult PK and toxicity data are obtained. The agency also says that adolescent patients should only be enrolled in early phase trials when they have relapsed or refractory cancer, or a cancer with no curative standard treatment available.
But for activity estimating and confirmatory trials, FDA says that adolescents can be enrolled at the same time as adult patients.
When it comes to dosing, FDA says that the appropriate dose for adolescents should be based on whether the adult dose is adjusted for body size or fixed.
For drugs with an adjusted dose, FDA says adolescents should receive the same body size-adjusted dose as adults. For drugs given as a fixed dose, FDA says that sponsors should define a minimum weight threshold to prevent smaller than average adolescents from exceeding the intended exposure to the drug.
FDA also says that sponsors should pay close attention to any age-related differences in safety data, and that sponsors should have a plan for evaluating potential developmental toxicities.
In addition, FDA says that institutional review boards (IRBs) reviewing trials that allow for adolescent enrollment must adhere to regulations under 21 CRF 50 subpart D, which lays out additional safeguards for children in clinical studies.