“If we could see that in the U.S., where we spend so much money on all these biologics, if the biosimilar could lower competitors’ prices, that would be a good thing, even if it’s only to a 30% discount,” Dr. Kim says.
Another potential reason for the lower-than-expected uptake level is that “Inflectra is basically the biosimilar of infliximab. It’s not the most common or popular TNF inhibitor, probably because it’s one of the oldest TNF inhibitors, and it requires an infusion,” Dr. Kim explains. “The initial impact of this biosimilar infliximab on the overall market may not be that big because we don’t prescribe even the branded infliximab that much. I think this is just a first step.”
In preparation for the availability of biosimilars, it’s important to explain the distinction to patients. Dr. Kim says.,“I think these concepts or the term biosimilar’need to be recognized. They are similar to the branded drug, but not necessarily the same thing.”
She adds, “The other lesson there—and that we could potentially expect in the U.S.—is potentially to have some impact on the use of other biologic drugs, and maybe there’s an indirect effect on the overall use of biologic drugs in the U.S. It may not be true at the end, but that’s what I’m thinking.”
Yet another factor that may have affected Dr. Kim’s study is that “physicians are not likely to switch [a patient] from the branded to a biosimilar drug if the patient is doing well on the branded.” So, she adds, “it is likely that you will see the use of the biosimilar in patients who are newly starting infliximab, but the proportion of these people may be quite small.”
The introduction of additional biosimilars to market, and even multiple versions of biosimilar infliximab, for example, will inherently make things more complicated. For one thing, “safety or effectiveness related to two-way switching is unknown,” Dr. Kim says. Further, it would be ideal if biosimilar drugs [even for the same reference drug] are recorded in medical records and by third-party payers (e.g., Healthcare Common Procedure Coding System “J” codes) specific to each version of the drugs, but that will become increasingly complicated as more alternatives are introduced to a single reference drug. And then, “later on, we also need to worry about switching from branded to biosimilar #1 or to biosimilar #2, or between #1 and #2, so it will get more and more complicated in potentially unexpected ways,” Dr. Kim says.
