Disparities in access of GLP-1 receptor agonists in cancer patients with obesity or type 2 diabetes: A cascade-of-care analysis across the semaglutide shortage timeline.

193 Background: Cancer survivors with cardiometabolic risk factors often experience reduced access to evidence-based therapies, including GLP-1 receptor agonists (GLP-1RAs), despite elevated risk of diabetes and cardiovascular disease. In March 2022, a national shortage of semaglutide raised concerns that access disparities—particularly in vulnerable populations—could worsen under constrained supply. We aimed to characterize drop-off across GLP-1RA care steps and assess how cancer status and race modified prescribing disparities before and during the shortage. Methods: We conducted a retrospective cascade-of-care cohort study using the TriNetX research network. Adults (≥18 years) with a cancer diagnosis and a subsequent diagnosis of obesity or type 2 diabetes mellitus (T2DM) were included. Exclusion criteria were GLP-1RA contraindications, ECOG>2 or Karnofsky Performance Scale<40. Two cohorts were defined: those diagnosed with obesity/T2DM in the Pre-Shortage Era (Mar 2019–Aug 2021) and Shortage Era (Mar 2022–Aug 2024). The study design was two-fold: first, a cascade-of-care analysis evaluated progression across six stages (eligibility, clinical engagement, metabolic assessment, antidiabetes treatment initiation, GLP-1RA prescription, and persistent GLP-1RA use [≥180 days]), and second, cox proportional hazards models, adjusted for several clinical and demographic covariates, assessed the impact of both cancer status and race on GLP-1RA prescribing patterns. Results: Among 106,457 pre-shortage and 104,863 shortage-era eligible cancer patients, GLP-1RA prescribing increased from 1.4% to 2.8%, yet disparities widened. Cancer patients were significantly less likely to receive GLP-1RA therapy than matched non-cancer patients in both eras (pre-shortage: aHR 0.57, 95% CI 0.55–0.59; shortage: aHR 0.39, 0.38–0.40). Among all cancer survivors, Black patients had persistently lower prescribing rates vs. White patients (shortage: aHR 0.72, 0.64–0.81), while Asian patients experienced newly emergent disparities during the shortage (aHR 0.65, 0.53–0.79) that were not present prior. Fewer than 1% of cancer patients demonstrated persistent GLP-1RA use. The steepest cascade drop-offs occurred between treatment initiation and GLP-1RA prescription and again at sustained use. Conclusions: Despite overall gains in GLP-1RA prescriptions, the semaglutide shortage exacerbated disparities by both cancer status and race in cancer patients. Cancer survivors, especially Black and Asian patients, were disproportionately under-prescribed during the shortage period. These findings underscore the need for equity-centered allocation strategies and real-time monitoring during drug shortages to prevent the amplification of existing access inequities in high-risk populations.