What Influences Physicians' Decisions About Patient Suitability for Biosimilar Infliximab?

Prescribing physicians play a large role in the adoption of biosimilars for the treatment of patients with rheumatic diseases, so it is important to understand physicians’ perceptions of which patients are suitable for treatment with biosimilars in clinical practice.

A study of physicians in the European Union suggests that physicians were more likely to consider rheumatoid arthritis (RA) patients suitable for biosimilar infliximab when,

• The patients had been in care for a relatively shorter period
• Had higher disease severity
• Were more involved in their treatment decisions.

The investigators performed a medical chart review of RA patients of physicians (primarily rheumatologists) in hospitals and private practices in the United Kingdom, France, Germany, Italy, and Spain to collect de-identified data on patient diagnoses, treatment patterns, dynamics, and patient symptomology and disease status. Physicians identified whether patients were suitable for biosimilar infliximab, and if they were, rated how likely they would be to prescribe the product to them when it became available. [Biosimilar infliximab (Inflectra/Remsima) was approved by the EMA in September 2013.] The analysis compared patients who were considered suitable for biosimilar infliximab with those who were not considered suitable per physician judgment, excluding those who previously failed infliximab.

Patients currently on (or discontinued within the past 3 months) a biologic drug and who were visiting each center during the screening period were selected for medical chart review. A total of 1204 patients were included in the analysis, 425 of whom were identified by the physicians as being suitable for biosimilar infliximab. Fifty-five percent of these were rated greater than or equal to 5 and 26% at 4, on their likelihood of being prescribed the infliximab biosimilar (7, extremely likely; 1, not at all likely). The physicians were screened for practice duration and patient volume, and were recruited to be geographically representative.

The study also concluded that physicians were not “readily prepared to prescribe the biosimilar to all infliximab biosimilar—suitable RA patients,” and the authors recommend studying this issue further to understand the drivers behind physician perception of which RA patients are suitable for treatment with biosimilar infliximab.

Among physicians, concerns about switching patients from Remicade to biosimilar infliximab remain because the approved infliximab biosimilar has not been designated as interchangeable by the FDA. Some studies have suggested that biosimilar switching is not suitable for all patients. For example, a 2016 Spanish study presented at the 2016 European League Against Rheumatism Annual Congress suggested antibody-positive patients being treated with Remicade should not be switched to treatment with the biosimilar infliximab because the antibodies will interact with the new drug and potentially lead to a loss of response. Lead author Daniel Nagore, MD, said, “While most studies show there are no significant differences in clinical response between a biosimilar and the original product, some physicians and patient advocacy groups have expressed concern about how interchangeable they really are, and whether it is safe to switch from the brand name version to the biosimilar.”