“If I see a good response, I may recommend staying the course or adding additional DMARDs. However, if the response is minor and the burden of disease is high, I will recommend a self-injectable biologic therapy. This requires a lengthier discussion [because] patients are not only concerned about administering injections and understanding how to minimize infectious risk, but also [in] gaining a sense of the financial cost.”
Dr. Piecyk says self-injectable forms of biologics are becoming more popular as an alternative to intravenous infusions. Abatacept and tocilizumab are two biologics that were previously available only as intravenous infusions. “Many patients prefer fewer trips to the doctor’s office,” she says.
Follow-on Biologic Response Modifiers
Follow-on biologics are generic biologics, and are made to be similar to existing biologics. However, unlike generic forms of synthetic DMARDs, these are complex biologic compounds, and they require biotechnological manufacturing using living tissue.
The U.S. Food and Drug Administration (FDA) recognizes two categories of follow-on biologics: biosimilars, which have the same mechanism of action but no clinically significant differences in safety or efficacy as the original biologic (also called a reference product), and interchangeables, which must meet the biosimilar standard and are expected to produce the same result in any given patient. In some states, pharmacists can substitute interchangeables without the prescribers’ knowledge.
Although no biosimilars are currently approved for rheumatology use in the U.S., an infliximab biosimilar called Remsima has been used in Europe to treat RA. The drug’s manufacturer, Celltrion Healthcare, is applying for FDA approval in the U.S.
‘I’ll explore the patient’s values, their concerns about the disease & what they have read about in terms of its treatment & risk tolerance. Finally, we develop clear goals for treatment.’ —Dr. Vivian Bykerk
The introduction of follow-on biologics and the approval of the first biosimilar in the U.S., Sandoz’s filgrastim-sndz (Zarxio) for Amgen’s reference product, filgrastim (Neupogen), is used by hematologists. “Approval of biosimilars will add complexity to rheumatology practice when RA drugs are approved in the United States,” Dr. Goodman says. “The advantage of follow-on biologics is that they cost less than current biologics and will, therefore, be more available to RA patients.”
Because biologics are large, complex molecules manufactured using cell lines in a precisely controlled environment, concern exists that small changes could result in an immune response to the drug with loss of efficacy. This concern will have to be addressed in large, long-term clinical trials, Dr. Goodman says.
