Biosimilar drugs could receive expedited FDA endorsement

Washington -- A manufacturer of a so-called biosimilar drug can receive expedited approval if it demonstrates that the product has no meaningful clinical differences from an approved original biologic drug, according to a Food and Drug Administration draft proposal released Feb. 9.

However, the FDA is not proposing one standardized process for approval of categories or classes of biosimilars. The agency will examine each application to determine the clinical requirements for approval, which may or may not include clinical studies, according to the proposal.

"If you are a biosimilar developer, this [proposal] will help clarify much of what's been on your mind," said Rachel E. Sherman, MD, MPH, associate director for medical policy at the FDA's Center for Drug Evaluation and Research, during a Feb. 9 conference call with reporters. "We're trying to send the signal that it's not one size fits all. It's product by product."

Biologics include a variety of vaccines, blood and blood components, gene therapies, tissues and proteins, according to the FDA guidance. Biologics are made using complex, large molecules and typically are significantly more difficult to manufacture than small-molecule drugs, such as aspirin. A biosimilar is a product based on an original biologic that has no meaningful clinical differences from the original.

The 2010 national health system reform law gave the FDA the authority to develop an approval pathway for biosimilars. The FDA issued the draft proposal to explain in greater detail its scientific requirements for approval. Under the proposal, biosimilar drugs could have different delivery mechanisms, formulations, narrower clinical uses and other differences with the biologics after which they are patterned.

The health reform law also provided at least 12 years of protection to original biologic drugmakers before other manufacturers can use data from the original drug to make a biosimilar.

The FDA will consider relying on existing data from European clinical trials and other studies to help expedite biosimilar approvals, Dr. Sherman said. "We do not want companies doing studies that do not need to be done."

The FDA intends to render a decision on each biosimilar application within 10 months of receiving it, she said. The agency continuously has been advising drug manufacturers on its approval process but had not yet received a biosimilar application as of early February.

Dr. Sherman said biosimilar manufacturers could apply to have their products certified as interchangeable at the time they seek biosimilar designations for the same products. The FDA also would render decisions on these certifications within the 10-month review window. An interchangeability designation would allow a biosimilar drug to be substituted by a pharmacy without physician approval.

Interchangeability will require clinical trial data and will be a high standard to meet, but not an impossible one, Dr. Sherman said. Manufacturers would be required to demonstrate that switching back and forth -- perhaps multiple times -- between an original biologic and a biosimilar produces the same clinical results in patients, she said.

American Medical Association policy supports the development of an approval pathway for biosimilars, also known as follow-on biologics. But the Association had said such a pathway should not compel physicians to consider biosimilars as interchangeable.

"The AMA is pleased the FDA's proposed approval pathway for biosimilars prioritizes product efficacy and patient safety and creates a more rigorous standard for achieving interchangeability," said AMA President Peter W. Carmel, MD. "We look forward to clear FDA guidance about the naming of biosimilars to avoid confusion among prescribers and patients and also about strategies for physician and patient education on these products."

The Biotechnology Industry Organization and the Generic Pharmaceutical Assn. said they will study the FDA proposal carefully and submit comments to the agency, which are due by April 16.

The Biotechnology Industry Organization "encourages the FDA not to delay approval for new innovator biologics as it undertakes a pathway for approving biosimilars," BIO President and CEO Jim Greenwood said in a statement. "The needs of patients awaiting innovative cures and therapies for unmet medical needs must remain paramount."

The FDA also provided a question-and-answer document to address some common inquiries the agency has received since holding a public meeting on a biosimilar approval pathway more than a year ago. The agency intends to have another public meeting to solicit feedback on the guidance and to help develop the next steps on biosimilars, Dr. Sherman said. It also plans to update the Q&A document periodically.