On April 11, 2016, the FDA approved a second biosimilar product— Inflectra is biosimilar to Janssen Biotech, Inc.’s Remicade (infliximab), which was originally licensed in 1998. Inflecta is used for multiple indications and is administered by intravenous infusion. The agency expects to approve other biosimilars in the future. The FDA approved Zarxio (filgrastim-sndz), a biosimilar to Neupogen (filgrastim), in March 2015. Neupogen is used to treat neutropenia, a lack of certain white blood cells caused by cancer or a bone marrow transplant.
“Biologics are different from conventional medications. Conventional medications—drugs—are generally made from chemicals, or chemically synthesized, and therefore their structure can be relatively easily defined,” according to Leah Christl, Ph.D., Associate Director for Therapeutic Biologics at the FDA.
Biologics are medicines that generally come from living organisms, which can include humans, animals and microorganisms such as yeast and bacteria. Unlike conventional medications, biologics cannot be made by following a chemical “recipe.” “Biologics come from living organisms that are variable in nature. In addition, they are generally more complex and not as easy to define and characterize,” Christi adds. Because of that, developing biologics is a far more complex process than manufacturing drugs.
Just as it does for drugs, the FDA rigorously and thoroughly evaluates a biologic’s safety and effectiveness before granting it approval. Currently, biologics are among the fastest growing segments of the prescription product market.
A biosimilar is a type of biologic that is highly similar to another, already FDA-approved biologic (known as the reference product). “It is important to note that a biosimilar is not just like a generic drug,” Christl adds. “Because of the differences in complexity of the structure of the biologic and the process used to make a biologic, biosimilars are not as easy to produce as generics, which are copies of brand name drugs. A biosimilar is not an exact duplicate of another biologic; rather, a biosimilar is highly similar to the reference product.”
Before approving a biosimilar, FDA experts must also first verify that there are no clinically meaningful differences between the biosimilar and its reference product. In other words, it will work the same way as the reference product for its approved indications. This abbreviated licensure pathway under section 351(k) of the Public Health Service Act permits reliance on certain existing scientific knowledge about the safety and effectiveness of the reference product, and enables a biosimilar biological product to be licensed based on less than a full complement of product-specific preclinical and clinical data.
Also, the biosimilar must have the same strength and dosage form and route of administration as the reference product. The biosimilar must be manufactured following Current Good Manufacturing Practices. “Patients can rest assured that they’ll be able to rely upon the safety and effectiveness of an FDA-approved biosimilar, just as they can rely on the reference product that the biosimilar was compared to,” Christl says.
“Biosimilars are likely to create greater competition in the medical marketplace,” Christl says. This could not only increase treatment options for patients but also lead to less expensive alternatives to comparable products. With an increasing number of biosimilars on the market, consumers may expect to get equally safe and effective treatment, but at lower costs, she says.
For example, Inflectra is biosimilar to Remicade (infliximab) and both products are approved for multiple conditions, including Crohn’s disease, ulcerative colitis, rheumatoid arthritis, psoriatic arthritis, plaque psoriasis, and ankylosing spondylitis.
See the FDA Consumer Update
See the FDA Announcement
See also Medical Law Perspectives, September 2015 Report: Arthritis Pain and Inflammation: Diagnosis and Treatment Risks
See also Medical Law Perspectives, May 2013 Report: Drugs, Dosage, and Damage: Physician Liability for Prescribing or Administering Medication