As the development of biosimilars in rheumatology is exploding, will the promise of costs savings/containment be realized?
There are studies that suggest that a modest reduction in cost must be present before prescribers will use a less costly copy (true in the generic world and seems to be true with biosimilars). Is that a 30% minimum reduction (or more, or less)?
Will we just treat more patients by rationalizing that the cost savings allow for more patients to have access since the biologics market in rheumatology has been increasing by at least 6% per year for 15 years?
Why don't prescribers do non-medical switches?
If one believes (once regulators approve a biosimilar) that the expected safety, benefits, side effects, immunogenicity and tolerability are virtually the same with a biosimilar compared to an originator, and they are less costly, why aren't more switches occurring? There is a psychology of leaving well enough alone, inertia to have the discussion with patients if not forced to switch, and uncertainty about long-term benefit/risk/durability, despite the evidence from switching trials.
We are used to having someone else mandate a generic when we prescribe a branded product and thus do not enter into the usual discussion about generics' pricing and automatic substitutions. Our gastroenterologist colleagues have totally switched their opinions on biosimilars over the last few years with >70% opposing switching to >70% now supporting biosimilars. Some of that may be due to the infliximab Crohn's study (Inflectra/Remsima vs Remicade). The attitude shift does not yet extend to switching all patients who are stable on their current biologic.
Scandanavia takes the lead in biologic switches from originator to biosimilar, likely due to extreme price cuts in the cost of the latter group of drugs. At this year's ACR meeting, the Danish presented data on non-medical infliximab switches (Glintborg B, et al. #1997). In stable Remicade users who switched to Remsima, there was no negative impact on drug concentration or presence of anti-drug antibodies at 3 and 6 months.
Guro Løvik Goll et al. (#19L) presented data from the real-world randomized switch trial (NOR-SWITCH) that included multiple diseases where patients were randomized to stay on Remicade or switch to biosimilar infliximab (CT-P13, also known as Remsima or Inflectra). The study found comparable results (the biosimilar was not inferior to the originator). Some people pointed out minor between-group differences, but one would expect some differences in a RCT even if there was a trial of Remicade vs. Remicade, so these differences did not affect the overall conclusion.
One unanswered question is, which biosimilar to use? There are approximately 35 biosimilars in development for rheumatology, so many will not survive within each country and the advantages of one over another will be access and/or data (trials within the diseases we use them in). We may have patients switching from one product to another based on availability of drug or best cost negotiations changing over time, but that is how it works in a system where the players (available biosimilars), costs and payers change over time.
So, what will you do when you talk to your patients after this meeting who are on biologics that have or will have biosimilars approved in your area? You will have to weigh your belief in the similarity of these products, your fear of unknown long-term immunogenicity, and your ability to potentially save money. Not an easy answer for most...
Dr. Janet Pope is Professor of Medicine at Western University and Division Head of Rheumatology. Dr. Pope's research interests include epidemiologic studies in scleroderma, classification criteria in systemic sclerosis, systemic lupus erythematosus and rheumatoid arthritis.View Full Bio