Abstract 3690: The impacts of prior authorization policy reforms on breast cancer treatment

Abstract Prior authorization (PA) is a widely used cost-containment tool that requires third-party approval for coverage of medical tests and treatments. This process is time-intensive for physicians and is frequently associated with delays in patient care; in cancer care, almost 80% of oral chemotherapies require PA, and most cancer patients undergoing PA report delays of two or more weeks. The burden of prior authorization is a growing concern, and major recent changes in state and federal policy aim to streamline and expedite PA. However, the impact of these policies on cancer care remains unclear. Using data from the Oncoshare database (2012-2020), we evaluate how two California laws (SB 866 and SB 282, passed in 2012 and 2014) affect medication utilization and time to treatment among breast cancer patients using a quasi-experimental design. While we observed no significant changes in medication utilization, both laws were associated with reductions in time to treatment. These findings suggest that PA reform improves timely access to cancer therapies. Citation Format: Margot Eliza Hutchins, Alyce Adams, Lin Ma, Alison Kurian, Mina Satoyshi. The impacts of prior authorization policy reforms on breast cancer treatment [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2026; Part 1 (Regular Abstracts); 2026 Apr 17-22; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2026;86(7 Suppl):Abstract nr 3690.