Pharmacists Lead, Physicians Lag? Provider Perspectives on Biosimilars and Interchangeability
A new cross-sectional survey of 249 US outpatient clinicians—150 physicians and 99 pharmacists who treat immunologic conditions—offers a timely snapshot of how front-line decision-makers view biosimilars and the US Food and Drug Administration (FDA) interchangeability designation. Respondents represented rheumatology, dermatology, and gastroenterology practices across over 30 states, with physicians reporting a median age of 50 years and 17.5 years in practice, and pharmacists a median age of 41 years and 13 years as licensed providers. Continuing education exposure was common but uneven: 65.7% of pharmacists versus 50.7% of physicians reported obtaining biosimilars-related continuing education units (CEUs).
Familiarity and comfort with biosimilars were generally high, yet not uniform. Across all providers, 92.8% described at least some familiarity with the FDA’s definition of a biosimilar, and 88.8% reported being at least somewhat comfortable using them. Familiarity dipped when the concept shifted to “interchangeability”: most rated themselves only “moderately” familiar with the FDA’s definition, and knowledge of state-level substitution laws was similarly middling. Notably, more pharmacists than physicians rated themselves “extremely familiar” with pharmacy retention of communication records (35.4% vs 20.0%), a practical detail that becomes important when substitutions occur under state law.
When it came to recommending products, pharmacists were more assertive than physicians. Nearly half of pharmacists (47.5%) said they were “extremely likely” to recommend a biosimilar for treatment-naive patients, compared with 31.3% of physicians. For patients already on a reference biologic, 47.5% of pharmacists and 38.7% of physicians said they were “likely” to recommend switching. These findings echo a recurring dynamic: pharmacists report more training and operational familiarity and are, in turn, more inclined to recommend biosimilars in both new-start and switch scenarios.
The most formidable obstacles were economic and payer driven. Among all respondents, payer coverage and formulary placement was the barrier most often rated “extremely significant” (51.0%), followed by patient affordability (41.0%). Pharmacists were especially attuned to patient cost, with 47.5% rating it an “extremely significant” barrier. Operational issues—such as administrative burden, billing complexity, and supply reliability—were frequently cited as at least moderately significant, underscoring that uptake hinges on more than clinical comfort.
Providers also identified clear levers to accelerate adoption. The strategies most often rated “likely” or “extremely likely” to improve uptake included generating real-world evidence and education specific to interchangeability (82.3%), FDA guidance for both treatment-naive (81.9%) and switching patients (81.6%), and practical training on billing and reimbursement (79.1%). Reducing patient cost sharing also ranked highly, reflecting the direct line from benefit design to bedside decisions.
For managed care stakeholders, the message is pragmatic: formulary clarity, aligned coverage, and predictable patient costs will do as much as clinical persuasion to move the market. Targeted education—especially on interchangeability criteria, substitution laws, and reimbursement workflows—can narrow remaining knowledge gaps between physicians and pharmacists. With 69 biosimilars approved as of April 2025 and more anticipated, investments in coverage policy, cost-sharing design, and provider education may yield near-term gains in biosimilar adoption and longer-term savings across immunology spend.
Reference
Ling YL, Gentile D, Kotomale A, et al. Real-world familiarity with US biosimilar regulatory guidelines and interchangeability state laws among pharmacists and physicians treating immunological disorders. J Manag Care Spec Pharm. 2025;31(6):552-564. doi:10.18553/jmcp.2025.31.6.552
