🔎︎
A Platinum Award-winning poster at the 2026 AMCP Annual Meeting in Nashville evaluated whether the Illinois biomarker testing coverage law, the first of its kind in the United States, improved access to molecular testing for cancer patients. The study was conducted by Ko and colleagues at Genentech using the IQVIA PharMetrics Plus closed health plan claims database.
Illinois implemented its biomarker testing law on January 1, 2022, requiring state-regulated insurance plans to cover medically necessary biomarker testing. The investigators used an interrupted time-series design to compare testing trends in fully insured and Medicaid plans, which were subject to the law, with self-funded plans, which were subject to federal regulation and not directly affected.
The study included 1,122 patients diagnosed with advanced non-small cell lung cancer or metastatic colorectal cancer between July 2020 and June 2023. Overall upfront biomarker testing rose from 79.2% to 89.7% during the study period, and multi-gene panel testing increased from 16.4% to 28.1%.
The legislation produced measurable results for the plans it targeted. Fully insured and Medicaid patients had 1.6 times greater odds of receiving any upfront biomarker testing compared to those in self-funded plans after the law took effect. The same 1.6-fold increase applied specifically to multi-gene panel testing. However, a 20.2 percentage-point gap in multi-gene panel use between self-funded and state-regulated plans persisted at the end of the observation period, with self-funded plans maintaining higher utilization.
The authors concluded that while the Illinois law significantly improved access to testing for state-regulated plan enrollees, additional policy measures were needed to close the remaining disparity and ensure equitable access to precision oncology diagnostics.
