by Amanda Conschafter, blog editor
The Food and Drug Administration has released its long-anticipated draft guidance on biosimilar labeling – but the document may leave some health care providers and patient advocates disappointed.
The draft guidance reminds readers that labeling, also known as prescribing information, must provide information that allows physicians to “use the drug safely.” For the agency, that means requiring a biosimilarity statement that identifies the medication as a biosimilar for health care providers and patients.
It also means requiring biosimilar drug labels to acknowledge the complexity of patients’ immunogenic responses to the sophisticated drugs. The draft guidance requires a label to state, in a subsection on immunogenic adverse reactions, that applying the reference product’s data on antibody development directly to the biosimilar may be “misleading.”
Taking the Generics Approach
On the topic of clinical trials data, however, the agency favors an approach more similar to that used by generic versions of traditional drugs. Clinical studies on biosimilars are designed to demonstrate biosimilarity to the reference product, the agency explains, not to independently establish the safety and efficacy of the biosimilar. Thus, the FDA considers the biosimilar’s clinical trials data to be inessential for labeling. The data would not be “relevant” to health care providers, the agency argues, suggesting that including the data could even “cause confusion” and encourage an “inaccurate” understanding of the biosimilar’s risks and benefits.
The agency instead directs biosimilar prescribing information to use data from the reference product’s label.
The decision clashes with requests from health care providers and patient advocates. They have urged the FDA to require clinical trials data from the biosimilar itself, as well as a statement on whether the data’s source were trials on the biologic or the biosimilar. This information could aid health care providers in determining which biosimilars might be appropriate for which patients.
The draft also overlooks physicians and advocates’ requests on the issue of indication extrapolation, the process by which the FDA relies upon a drug’s biosimilarity to approve it to treat diseases for which it has not been thoroughly tested. Given the wide range of conditions some biologic medicines treat, extrapolation may carry varying degrees of risk for patients. As physician and Alliance for Patient Access member Joshua Stolow, MD, explained during a recent FDA hearing, physicians need “transparent and clear information about what disease states have been tested and what the clinical outcomes and potential side effects of the approved product are for that indication.”
By directing biosimilar drugs to use indication information consistent with the reference product’s, however, the draft guidance undercuts physicians’ ability to know which approved uses reflect rigorous testing and which result from extrapolation.
The Food and Drug Administration will accept comments on its draft guidance for 60 days.