The panel explores the extrapolation of indications of biosimilars compared with the original product.
Anthony Mato, MD, MSCE: Marc, I want to talk about efficacy, because from a clinician’s perspective and a patient perspective, I’m sure this is where the majority of questions come up. Are there differences in efficacy for the biosimilar compared with the biologic? Then talk about the process of extrapolation of indications. We heard earlier that there are a minimal amount of studies that need to take place for a biosimilar to get approval—sometimes in patient populations that are not necessarily even the patients we might be treating. What are your thoughts about extrapolation to multiple indications based on the reference product’s label?
Marc Earl, PharmD, BCOP: When I think about extrapolating indications, I try to take a step back even from efficacy into what Bhavesh talked about before with the analytical studies that are done on these products. It’s very rigorous, and I think I would encourage folks to look at that science to understand if these products are very similar or not. That first step shows they’re very similar to one another, and most of the indication limitation is related to some patent issues with the branded product and maybe not so much clinical issues. I try to understand if I believe in the science or not, and I do. Therefore, it would be acceptable to extrapolate to any of the indications the FDA has. That’s caused a lot of conversation in our institution with a lot of our physicians and our pharmacy team. But I’ve been working with biosimilars for about 5 years and have really come to that framework.
Anthony Mato, MD, MSCE: Anyone else have any comments about efficacy? I’m sure this has to be the major focus of conversations that are happening around the country.
Tim Peterson, PharmD, BCOP: It’s also important to point out that upon applying for the extrapolation for additional indications for the originator product, that the manufacturer does need to prove that the mechanism of action is similar among those different indications. That’s a very important piece. They also need to prove that the bioactivity is similar regardless of the indication. They also need to show that they have acknowledged the different patient populations that are being treated with the different indications, comorbidities, medications, and even differences potentially in pharmacokinetics and pharmacodynamics in different patient populations for those indications. There is a lot that goes into the FDA approving those additional indications. It’s not simply just an extrapolation for all indications. They could even apply for fewer than the originator indications if they chose to do so.
Anthony Mato, MD, MSCE: Just to clarify for the audience: the biosimilar can never have more indications than the originator product, correct?
Bhavesh Shah, RPh, BCOP: That is correct, absolutely.
Anthony Mato, MD, MSCE: It will always have the same or a lesser number but never more, and it can never be studied in a unique way beyond the originator product.