Biosimilar uptake in Thailand: from physician's attitudes through budget impact

Background: Biosimilars offer potential to reduce healthcare costs, but their adoption faces several barriers. In Thailand, although biosimilars are available, key physician-related factors - such as familiarity, attitudes, and decision-making influences - remain unclear. These behavioral aspects can affect uptake and have significant implications for national healthcare budgets. This study aimed to propose policy options to enhance biosimilar uptake and reduce budget impact.Methods: A three-phase approach was used. Phase 1 applied an extended analysis framework using survey data from Thai physicians to assess familiarity, attitudes, influencing factors, and sources of biosimilar information. Statistical tests examined associations and correlation strengths. Phase 2 conducted a budget impact analysis using trastuzumab for early-stage breast cancer as a case study, following ISPOR guidelines. Phase 3 proposed policy options based on integrated findings.Results: Eighty-two physicians participated. Medical specialty and self-assessed familiarity were significantly associated with biosimilar prescribing (p < 0.05). 75.6% had adequate familiarity, and 69.5% showed favorable attitudes. However, attitude was not significantly associated with prescribing status. Familiarity and attitude were also not significantly correlated. Key influencing factors were efficacy data, safety information, and clinical guidelines. Main concerns included regulatory processes and post-marketing surveillance. The five-year budget impact was estimated at 24.63 million Thai Bath. Sensitivity analysis showed market share notably influenced outcomes including cost saving. Scenario analyses suggested that policy-driven uptake could enhance cost savings. Fourteen policy options were proposed, categorized into: (1) education and knowledge dissemination, (2) enabling environment for biosimilar use, and (3) building trust among stakeholders.Conclusions: While physicians generally showed positive familiarity and attitudes toward biosimilars, remaining gaps should be addressed to improve adoption and confidence. This study indicates that addressing behavioral barriers could support broader uptake, greater cost savings, and should improve patient access. The proposed policy options offer actionable strategies for promoting biosimilar use and achieving sustainable healthcare savings in Thailand.