Timely next-generation sequencing testing in patients with metastatic prostate cancer: A comparative analysis between Medicare Advantage and traditional Medicare.

320 Background: Next-Generation Sequencing (NGS) testing has become a cornerstone of personalized medicine in cancer care. With Medicare Advantage (MA) now covering nearly half of all beneficiaries, understanding differences in access to timely NGS testing between MA and Traditional Medicare (TM) is crucial, particularly given MA’s potential restrictions. This study aims to evaluate the effectiveness of MA plans on timely NGS testing in patients with metastatic prostate cancer (mPCa). Methods: This retrospective cohort study was based on the Flatiron Health deidentified Database, comprising electronic health record-derived data from ~280 cancer practices across the US. Our study included patients aged 65 or older, diagnosed with mPCa since 2018, and exclusively enrolled in TM or MA, either before or within 90 days following mPCa diagnosis. We compared the rates between TM and MA, using three timeframes—45-, 90-, and 180-days post-mPCa diagnosis. NGS testing was defined as any tissue or liquid genomic testing resulted within the time frame of interest. Multivariate logistic regression with inverse probability of treatment weighting was used, adjusting for demographics, year of mPCa diagnosis, practice setting, and baseline ECOG score. Results: Among the 1,582 MA patients (mean age: 75.9 ± 5.8) and 2,749 TM patients (mean age: 75.4 ± 5.8), significant proportions were from community practice (MA: 78%, TM: 80%) and were characterized by being White (MA: 59%, TM: 65%), aged 75 to 85 (MA: 54%, TM: 57%), having higher socioeconomic status (SES 4 or 5: MA: 40.3%, TM: 47.5%), presenting with de-novo mPCa (MA: 53%, TM: 54%), and having better baseline functional performance (ECOG 0 or 1: MA: 70%, TM: 69%). Since 2018, 8.8%, 14.5%, 18.8% of MA patients and 10%, 14.6%, 17.6% of TM patients received NGS testing at 45, 90 and 180 days, respectively. Notably, 63.4% and 60.8% of MA and TM patients, respectively, did not have any NGS testing. After adjusting for covariation, MA was associated with a 26.2% (OR=0.74, 95%CI 0.59-0.92), 16% (OR=0.84, 95%CI 0.7-1.01), 7.8% (OR=0.92, 95%CI 0.78-1.09) lower chance to receive timely NGS testing at 45 days, 90 days and 180 days, respectively. Conclusions: Patients with mPCa enrolled in MA are less likely to receive timely NGS testing compared to TM. The high rate of delayed or no testing underscores disparities in access, especially among MA patients. Policymakers should streamline approvals to ensure timely, high-quality care for all Medicare beneficiaries.