Unveiling the Biosimilar Paradox of Oncologists' Perceptions and Hesitations in South Korea: A Web-Based Survey Study.

Introduction: Biosimilars offer a cost-effective alternative to original biopharmaceuticals with comparable efficacy and safety. The perception and familiarity of prescribers toward biosimilars play a critical role in their market penetration. Yet, few studies have explored the perception of oncologists toward biosimilars, much less in Asia.

Objectives: The objective of this study is to understand barriers of adopting biosimilars among oncologists and explore strategies to promote their use in clinical practice settings.

Methods: A web-based survey was conducted among Korean oncologists from September to October 2022, assessing their perception of biosimilars and prescribing practices.

Results: Among the 118 surveyed oncologists, 75.4% (89 out of 118) had previously prescribed biosimilars. When asked about their preference, 48.3% (57 out of 118) of the respondents preferred originators to biosimilars, whereas 16.1% (19 out of 118) favored biosimilars over the originators. The primary reason for preferring the originators was trust in safety and efficacy (94.7%, 54 out of 57). Still, a paradox was noted as 87.0% (47 out of 54) and 85.2% (46 out of 54) of these also acknowledged the comparable efficacy and safety of biosimilars. A relatively small number of the respondents (16.1%, 19 out of 118) did not consider prescribing biosimilars to biologic-naïve patients at all, and up to 56.8% (67 out of 118) expressed reluctance to switch prescriptions from originators to biosimilars. However, 90.7% (107 out of 118) of respondents considered changing their prescription to biosimilars if patients faced financial stress. Concerns regarding the efficacy when switching to biosimilars were expressed by 42.7% (38 out of 89) of oncologists with biosimilar prescribing experience, increasing to 69.0% (20 out of 29) among those without such experience.

Conclusion: Korean oncologists perceived biosimilars to be as safe and effective as originators. However, there is a notable mismatch between this perception and their prescribing practices, particularly among those who have not prescribed biosimilars before. The financial burden of patients served as a significant driver for prescribing biosimilars, yet marginal price differences between originators and biosimilars may be associated with the low adoption rate of biosimilars in Korea. Active price competition may enhance market penetration of biosimilars.