Changes in treatment (Rx) patterns and attrition rates in patients (pts) with metastatic clear cell renal cell carcinoma (mccRCC).

Gliceida Galarza Fortuna Huntsman Cancer Institute at the University of Utah, Salt Lake City, UT info_outline Gliceida Galarza Fortuna, Yeonjung Jo, Chadi Hage Chehade, Arshit Narang, Georges Gebrael, Vinay Mathew Thomas, Beverly Chigarira, Ethan Anderson, Archisman Mazumder, Zeynep Irem Ozay, Neeraj Agarwal, Benjamin L. Maughan, Umang Swami

Authors Gliceida Galarza Fortuna Huntsman Cancer Institute at the University of Utah, Salt Lake City, UT info_outline Gliceida Galarza Fortuna, Yeonjung Jo, Chadi Hage Chehade, Arshit Narang, Georges Gebrael, Vinay Mathew Thomas, Beverly Chigarira, Ethan Anderson, Archisman Mazumder, Zeynep Irem Ozay, Neeraj Agarwal, Benjamin L. Maughan, Umang Swami Organizations Huntsman Cancer Institute at the University of Utah, Salt Lake City, UT, University of Utah/Huntsman Cancer Institute, Salt Lake City, UT, Gazi University Faculty of Medicine, Ankara, Turkey, Huntsman Cancer Institute, Salt Lake City, UT Abstract Disclosures Research Funding No funding sources reported Background: Rx landscape of mccRCC has evolved rapidly with the approval of antibodies directed against programmed cell death protein-1 (PD-1) in combination with cytotoxic T-lymphocyte-associated protein 4 (CTLA4) or vascular endothelial growth factor receptor tyrosine kinase (TKI) inhibitors. However, real-world data on Rx trends and attrition before and after PD-1 inhibitor approval are lacking. Herein, we analyze them in a large real-world cohort in the United States. Methods: This IRB-approved retrospective study used the nationwide Flatiron Health electronic health record (EHR)-derived de-identified database. Inclusion: Metastatic RCC with clear cell histology diagnosed between 1/1/2011 to 1/31/2022 receiving Rx with opportunity of at least 1 year follow up. Exclusion: Pts needing Rx for ≥2 malignancies. Based on the approval date of PD-1+CTLA4 of 4/16/18, pts were separated into 2 groups: b2018 (1L Rx before 4/16/2018) and a2018 (1L Rx after 4/16/18). Landmark analysis was performed at 1 year after Rx discontinuation to identify pts who died, were alive but did not need Rx, or starting next-line Rx. All analysis was done using R version 4.2.3. Results: Of 12707 pts, 7923 met the eligibility criteria (b2018: 4561 pts and a2018: 3362 pts). Rx trends are summarized in the table. 1L Rx for the majority of pts changed from TKI monotherapy (mono; 79%) b2018 to PD-1 combination therapies a2018 (58%). TKI mono remained the most common Rx in both groups after 1L (Table). In the b2018 cohort, 58% of patients received 2L Rx, and 32% received 3L. In the a2018 cohort, 42% and 16% received 2L and 3L, respectively. At 1-year landmark analysis after 1L discontinuation: in the b2018 group, 58% pts received next Rx, 30% died without further Rx, and 12% were alive without Rx while in the a2018 group, 42% pts received next Rx, 26% died without further Rx and 32% were alive without Rx. Conclusions: Despite the increase in the utilization of PD-1+CTLA-4 and PD-1+TKI regimens since 2018, a significant number of patients still did not receive novel combination regimens in the 1L mccRCC setting in this real-world population in the United States. Furthermore, with the uptake of PD-1 based combinations in 1L, a higher proportion of pts experience treatment free interval or were alive without further therapy at 1 year landmark analysis after 1L Rx discontinuation. These findings need validation in other datasets and can help patient counseling in clinics. Rx trends for mccRCC. Rx 1L b2018 n (%) 1L a2018 n (%) 2L b2018 n (%) 2L a2018 n (%) 3L b2018 n (%) 3L a2018 n (%) Overall 4561 3362 2639 1408 1458 551 TKI 3595 (79%) 880 (26%) 1029 (39%) 630 (45%) 688 (47%) 285 (52%) PD-1+CTLA-4 26 (0.6%) 1079 (32%) 69 (3%) 113 (8%) 48 (3%) 37 (7%) PD-1+TKI 23 (0.5%) 862 (26%) 86 (3%) 356 (25%) 75 (5%) 123 (22%) PD-1 170 (4%) 475 (14%) 807 (31%) 251 (18%) 340 (23%) 49 (9%) Others 747 (16%) 66 (2%) 648 (25%) 58 (4%) 307 (21%) 57 (10%)