This bill mandates the use of biosimilar medicines under health benefit plans in Arkansas, requiring healthcare providers to prescribe these alternatives when available. It introduces a new subchapter to the Arkansas Code, defining key terms such as "beneficiary," "biosimilar medicine," and "health benefit plan." The legislation stipulates that if a healthcare provider initiates a prescription biological product drug therapy for a beneficiary who has not previously been treated with that product, they must prescribe a biosimilar medicine if one is available. Additionally, health benefit plans are required to maintain an accessible formulary that lists all covered drug products, including any restrictions or tiering structures.

The bill also outlines provisions for generic drugs and biosimilar medicines, ensuring that if these alternatives are marketed at a lower wholesale acquisition cost than their reference products, they must be made available on the formulary with favorable cost-sharing arrangements. It clarifies that health benefit plans are not obligated to continue coverage for brand drugs once a generic or biosimilar is available, nor are they required to cover any drug deemed medically inappropriate or not cost-effective by their formulary committees. The act is set to take effect on January 1, 2026.