To assess the patients' information about biosimilars and to identify the patients' incentives and deterrents to concur with the use of biosimilars.
Nation-wide cross-sectional study assessing information and concerns about biosimilars of French patients treated for rheumatic inflammatory diseases, whether they were treated or not by a biological DMARD. The assessment was available online from March to July 2017.
Among the 629 respondents, 43% knew what biosimilars were. The main sources of information were rheumatologists and patient associations. Among patients treated with a biosimilar, 44% were not informed before they received the treatment. The patients' concerns focused on the non-similar molecular structure (46%), efficacy (60%) and safety (57%) comparatively to the originator biologic. 15% of respondents would refuse to switch their biologic to its biosimilar. More than 50% of respondents would warily accept to switch medications and interrupt the treatment if in doubt. Being informed about biosimilars and a good understanding of the definition of biosimilars were characteristics associated with better adherence to biosimilars. The rheumatologist was considered the most influent source of information about biosimilars and was considered reliable when deciding to switch a biologic to its biosimilar. Patient were reluctant to substitution of the medications by pharmacists (2%). Medico-economical issues acted as an incentive and a deterrent to accept the switch of medication.
Biosimilars are largely unknown to patients. Information seems to be instrumental in improving the patients' adherence to biosimilars and could help preserving the therapeutic relationship and avoiding a nocebo effect.