The Perception among Israeli Gastroenterologists Regarding Treatment of Patients with Biosimilar Medications.

: The ever-expanding entry of biosimilar drugs into the Israeli market requires doctors to decide whether to prescribe these medications. We aimed to assess the prevalence of biosimilar use and Israeli gastroenterologists' knowledge, experience, and perception of biosimilar treatment. : A cross-sectional survey was conducted among Israeli Gastroenterology Association (IGA) members between March and May 2022 using a structured 20-item questionnaire. : The questionnaire was completed by 108 gastroenterologists. Sixty-two percent prescribed biosimilars to their patients in the past year. Most of the patients (81%) were biologically naïve and only 19% were switched to a biosimilar. Most gastroenterologists (75%) answered that the effectiveness is the same. The rates of resistance to switching were 19%, 36%, and 70% for patients in remission for over two years, pregnant women, and difficulty reaching remission, respectively. In cases seeing a lack of response after switching, most physicians chose to change the mechanism of action, with only a small percentage returning to the brand-name drug. : Most Israeli gastroenterologists are not concerned about biosimilars' safety and efficacy. Despite this, most physicians will prefer the brand-name drug, especially regarding adalimumab. The populations in which physicians most oppose switching are those who have had difficulty achieving remission and pregnant women.