On February 9, FDA issued long-awaited guidelines designed, according to FDA drug division director Janet Woodcock, M.D., “to help industry develop biosimilar versions of currently approved biological products.” Paul Calvo, Ph.D., a director at Sterne, Kessler, Goldstein & Fox, told GEN, “There were no major surprises” in the guidelines.
“It is clear that FDA wants to move forward with biosimilar approvals and they will be looking to a totality of the evidence as the standard for a determination of biosimilarity.” He also commented that FDA wants a constant dialog with biosimilar sponsors and all the structural and functional data up front. “Their goal for the up-front data is to be involved in design of the clinical trials in order to maximize the data provided.”
FDA’s new documents describe a step-wise approval pathway, starting with extensive analytical, physico-chemical, and biological characterization data that will have to demonstrate a high degree of similarity to the reference product. FDA will evaluate that data and then provide advice to the sponsor on the extent and scope of animal and human testing needed to show biosimilarity. The agency will consider multiple factors in making study determinations, including product complexity, formulation, stability, structure-function relationships, manufacturing process, and clinical experience with the reference product.
While the pathway to the agency’s decision making will be abbreviated, “it will depend on existing data,” Rachel Sherman, M.D., director of the Office of Medical Policy in FDA’s Center for Drug Evaluation and Research, said during a conference call. “We do not want companies repeating studies that do not need to be done.” As to whether most biosimilar applicants will be expected to carry out clinical trials, decisions will be made on a product by product basis.
Another topic of note is that the FDA has said that there could be extrapolation of clinical data to other diseases to give companies developing biosimilars approval for use in multiple indications for a given product. “But for therapeutics like Rituxan with two disparate indications, one for lymphoma and another for rheumatoid arthiritis, two sets of clinical trials will likely be required,” Dr. Calvo explained.