e13673 Background: Targeted treatments (TT) have been approved for pts with mNSCLC harboring ADO in the 1L setting in recent years. This study aimed to understand if subpopulations of mNSCLC pts harboring ADO do not receive equitable access to guideline recommended 1L TT in US clinical settings. Methods: This retrospective study used the Flatiron Health electronic health record-derived, US nationwide, de-identified database. Pts with de novo mNSCLC (stage IVA or IVB) diagnosed between 4/1/2018-6/30/2023 were included if they were ≥18 y, had ≥2 visits after advanced diagnosis (aDx) and ≥90 days follow-up, received any biomarker testing prior to 1L Tx initiation, and harbored ADO (ALK, BRAF, EGFR, MET, NTRK, RET and/or ROS1). Results: Overall 2165 pts met study criteria: mean age was 67 y, 65% female, 11% Medicare insured, 58% commercial insured, 76% treated in the community setting with 11% Medicare and 64% commercial insured (vs 12% and 41% treated in the academic setting with Medicare and commercial insurance), and 45% had smoking history; of non-missing data, 12% had lowest socioeconomic status (SES), 26% with highest SES, 95% had non-squamous NSCLC, and 83% had ECOG performance status ≤1. The median time from aDx to testing result among the 53% non-Latinx (nL) white, 8% nL Black, 7% Latinx, 13% nL Asian, 7% nL other and 13% missing race/ethnicity was 21, 23, 24, 21, 23 and 20 days, respectively; median time from aDx to TT initiation was 38, 38, 43, 36, 47 and 37 days, respectively. Pts significantly more likely to receive 1L TT were (Table): pts of color vs white pts; Medicare vs commercial insurance at community sites; without vs with smoking history. Pts less likely to receive 1L TT were (Table): community vs academic sites; Medicare vs commercial insurance at academic sites. Consistent findings were seen in the 1817 pts with established 1L ADO (ie. ALK, EGFR or ROS1) (Table). Conclusions: When pts with mNSCLC harboring ADO had biomarker testing before Tx initiation, contrary to prior observed racial inequity in NGS testing, there was no racial inequity in receiving 1L TT. However, inequity in receiving 1L TT was observed by insurance type, smoking history and site of care. Interventions are warranted to address these contributors to 1L TT inequities. [Table: see text]