Perceptions towards biologic and biosimilar therapy of patients with rheumatic and gastroenterological conditions.

Background: Biologic and targeted synthetic disease modifying agents (b/tsDMARDs) have broadened the treatment landscape for autoimmune diseases particularly in patients refractory to conventional DMARDs. More recently, the introduction of biosimilars has reduced the price of bDMARDs, potentially improving accessibility. Though efficacy and safety have been described, patient attitudes to b/tsDMARDs are not well-understood. We aim to investigate patients' beliefs about biologic and biosimilar therapy, and the factors influencing their perceptions.

Methods: Patient consumer groups (Arthritis Australia, Crohn's and Colitis Australia) assisted in advertising an online questionnaire for people with a self-reported diagnosis of inflammatory arthritis (IA) or inflammatory bowel disease (IBD). The questionnaire incorporated the Belief about Medicines Questionnaire (BMQ) and the single-item literacy screener (SILS). Sources and favourability of biologic/biosimilar information were analysed, using the chi-square and a non-parametric trend test for unordered and ordered categorical variables respectively, comparing respondents with IA and IBD.

Results: Eight hundred and thirty eight people (686-IA, 144-IBD, 8 both) responded. 658 (79%) used b/tsDMARDs. The BMQ demonstrated high necessity belief (median 4.2) with moderate concerns (median 2.8) about biologics. 95% of respondents obtained medication information from specialists though most used multiple sources (median 4). The most positive resources were specialists and specialist nurses. 73/141 (52%) respondents with IBD obtained information from specialist nurses compared with 202/685 (29%) with IA (p = 0.012). Respondents with limited reading ability on SILS were more likely to discuss information with a general practitioner or pharmacist. Younger respondents and those with higher BMQ concern scores more frequently consulted less reliable sources (e.g. social media). 502 respondents (60%) answered the biosimilar questions. Only 23 (4.6%) reported currently using a biosimilar and 336 (66.9%) were unsure if biosimilars were available in Australia. Specialist recommendation was the most frequent factor that would influence a patient to change from originator to biosimilar (352/495, 71.1%).

Conclusions: There is a high level of trust in specialists' recommendations about b/tsDMARDs, although most people also utilise additional information sources. Contextual factors influencing resource selection include age, reading ability and degree of concern about medicines. People with IA and IBD have similar attitudes though those with IBD more frequently access specialist nurse advice.