Real-world rates of FDA-approved targeted therapy and immunotherapy prescriptions for metastatic colorectal cancer patients in the VA’s National Precision Oncology Program (NPOP).

person Alice Nono Djotsa Center for Innovations in Quality Effectiveness and Safety, Houston, TX info_outline Alice Nono Djotsa, David Winski, Theresa Hoang-Anh Nguyen, Sara Ahmed, John H Strickler, Daniel Jacob Becker, Vishal Vashistha, Michael J. Kelley

Authors person Alice Nono Djotsa Center for Innovations in Quality Effectiveness and Safety, Houston, TX info_outline Alice Nono Djotsa, David Winski, Theresa Hoang-Anh Nguyen, Sara Ahmed, John H Strickler, Daniel Jacob Becker, Vishal Vashistha, Michael J. Kelley Organizations Center for Innovations in Quality Effectiveness and Safety, Houston, TX, VA Boston Healthcare, Boston, MA, Baylor College of Medicine, Houston, TX, US Department of Veterans Affairs, Washington, DC, Duke University Medical Center, Durham, NC, Manhattan VA/NYU, New York, NY, Veterans Affairs Medical Center, Albuquerque, NM, Duke University, Durham, NC Abstract Disclosures Research Funding Other Government Agency VA National Precision Oncology Program Background: Colorectal cancer is the fourth most common cancer among Veterans and the third leading cause of cancer-related death in the USA. Use of comprehensive genomic profiling (CGP) to guide administration of FDA-approved biomarker directed therapies can improve outcomes among metastatic CRC (mCRC) patients. We sought to compute the rates of actionable biomarkers and prescriptions of associated FDA-approved therapies among Veterans in NPOP. Methods: The NPOP database was queried to identify mCRC patients who had undergone CGP via tissue or liquid biopsy between February 2019 and July 2022 and had one of the following 5 actionable biomarker profiles: NRAS / KRAS / BRAF wildtype, BRAF V600E, MSI-H, TMB-H, or NTRK fusion or rearrangement. The VA’s Corporate Data Warehouse (CDW) was queried to extract prescription data for seven FDA-approved biomarker-directed therapies (targeted agents and immune checkpoint inhibitors (ICIs)). Rates of CGP-directed therapy prescriptions were assessed based upon biomarker and patient characteristics (sex, race, ethnicity, and rurality). Results: A total of 908 mCRC patients underwent CGP, with 81.4% bearing colon adenocarcinoma (COAD) and 18.6% rectal adenocarcinoma (READ). Rates of actionable biomarkers associated with FDA-approved therapies were as follows: NRAS / KRAS / BRAF wildtype (34.4%), TMB-H (9.6%), BRAF V600E (7.7%), MSI-H (5.6%), TMB-H and MSI-H (5.6%), and NTRK Fusion or rearrangement (0.3%). The combined rates of any actionable variant were 47.4% for COAD and 44.4% for READ patients. Relative to patients without actionable biomarkers, patients with BRAF V600E mutations were more likely to be older and white; patients with NRAS / KRAS / BRAF wildtype were more likely to be younger (all p < 0.001). Among the 424 eligible patients, the frequencies of FDA-approved CGP-directed therapy prescriptions were as follows: MSI-H (70.7%), TMB-H (47.4%), NRAS / KRAS / BRAF wildtype (38.5%), and BRAF V600E (17.1%). Across all included biomarkers, African Americans (53.4%) were more likely to receive these therapies than whites (36.8%); and patients with prescriptions were more likely to be younger that those without (all p < 0.01). Conclusions: Nearly 30% of patients with MSI-H mCRC did not receive efficacious ICIs, and though disease laterality data was not readily available, a substantial number of eligible patients also did not receive EGFR inhibitors. This underuse of EGFR inhibitors has been reported previously [1].There were racial and age differences in prescription rates. Further studies should evaluate the barriers to prescribing CGP-directed therapies in the care of mCRC patients. Keywords: molecular testing, metastatic colorectal cancer, comprehensive genomic profiling, actionable biomarkers, FDA approved therapies, veterans. [1] Becker et al. 2021 PMID 34250412.