FDA Finalizes Guidance on Placebos and Blinding for Cancer Trials

The US Food and Drug Administration (FDA) on Wednesday finalized guidance recommending that drugmakers only use placebos in cancer clinical trials in select circumstances due to ethical concerns that would arise when alternative therapies are available.
 
According to guidance, placebos should only be considered in randomized controlled trials to treat oncologic disease or hematologic malignancy “when surveillance is standard of care” or in studies with “certain trial design features (e.g., when the trial uses an add-on design).”
 
“A placebo-controlled study design may be useful or preferred in maintenance therapy, in add-on trial designs, in trials of adjuvant therapies (for which standard of care is surveillance), and for indications where no treatment is available,” FDA writes.
 
The guidance provides a set of considerations for sponsors weighing a placebo-controlled trial design, noting that sponsors “should provide the rationale for the trial design” and a description of their plan for blinding and unblinding patients during the trial.
 
The six-page guidance finalizes a draft version issued in August 2018 and has been updated to clarify issues related to unblinding that were raised during the public consultation.
 
In a change from the draft guidance, FDA clarifies that when unblinding due to disease recurrence or progression that only the patient and investigator be unblinded, whereas the draft guidance only specified that the patient be unblinded.
 
FDA also maintains that patients and investigators should be unblinded when patients experience an adverse event suspected to be related to the investigational drug when managing the adverse drug would require treatment with “one or more drug products with substantial toxicity or invasive procedures.”
 
If the sponsor plans on maintaining blinding when a patient’s disease recurs or progresses or after an adverse event, FDA says the sponsor should provide a justification for maintaining blinding and acknowledge the risks of the approach in the informed consent documents.
 
FDA also updated the guidance to note that it does not address statistical considerations when unblinding data and simplified its title.
 
FDA