REAL-WORLD PREDICTORS OF NEOADJUVANT PEMBROLIZUMAB IN EARLY-STAGE TRIPLE-NEGATIVE BREAST CANCER: A UNITED STATES NATIONAL ELECTRONIC HEALTH RECORD ANALYSIS
Author(s)
Mahima Saini, B. Pharm1, Jacob T. Painter, MBA, PharmD, PhD2, Chenghui Li, PhD2, Corey J. Hayes, MPH, PharmD, PhD2, Corey L. Nagel, Ph.D., MPH, RN2, Sri Usha Jeevani Obulareddy, M.D.2.
1University of Arkansas for Medical Sciences (UAMS), Little rock, AR, USA, 2University of Arkansas for Medical Sciences (UAMS), Little Rock, AR, USA.
1University of Arkansas for Medical Sciences (UAMS), Little rock, AR, USA, 2University of Arkansas for Medical Sciences (UAMS), Little Rock, AR, USA.
OBJECTIVES: To characterize real-world pembrolizumab utilization patterns, and identify patient-, clinical-, and system-level predictors of pembrolizumab receipt in early-stage triple-negative breast cancer (TNBC) following FDA approval in July 2021. This study is critical for evaluating concordance with August 2021 NCCN treatment guidelines.
METHODS: A retrospective cross-sectional study was conducted among adults with Stage II/III TNBC diagnosed between September 2021 and May 2026 using Epic Cosmos, a U.S. electronic health record network. Patients were classified as receiving pembrolizumab plus chemotherapy or chemotherapy alone. Temporal uptake trends and time from diagnosis to initiation were described. Multivariable logistic regression identified independent predictors of pembrolizumab receipt, reported as odds ratios (OR) with 95% confidence intervals.
RESULTS: A total of 4,438 early-stage TNBC patients were included, of whom 3,606 (81%) received pembrolizumab plus chemotherapy and 832 (19%) received chemotherapy alone. Initiation was right skewed with peaks at 0, 7, 14, and 21 days post-diagnosis. Pembrolizumab receipt increased with each successive year of diagnosis (OR: 1.12 (1.05-1.19); p<0.001). Patients with Stage III disease had higher odds of pembrolizumab receipt compared with Stage II (OR: 1.84 (1.56-2.17); p<0.001). Increasing age at diagnosis was associated with lower odds of pembrolizumab receipt (OR: 0.98 (0.97-0.98); p<0.001). Patients with Grade 1/2 tumors had lower odds of receipt compared to those with Grade 3 tumors (OR: 0.79 (0.65-0.97); p=0.024). A pre-existing autoimmune diagnosis (OR: 0.81 (0.67-0.98); p=0.031) and higher area-level socioeconomic vulnerability (OR: 0.67 (0.51-0.90); p=0.007) were independently associated with lower odds of receipt. No significant associations were found between pembrolizumab receipt and race/ethnicity, state of residence, rurality, BMI, or comorbidity burden.
CONCLUSIONS: Clinical and tumor characteristics were the primary determinants of pembrolizumab receipt in early-stage TNBC, consistent with guideline-based prescribing. However, greater area-level socioeconomic vulnerability independently predicted lower pembrolizumab receipt, suggesting that access barriers persist even for guideline-recommended therapy.
METHODS: A retrospective cross-sectional study was conducted among adults with Stage II/III TNBC diagnosed between September 2021 and May 2026 using Epic Cosmos, a U.S. electronic health record network. Patients were classified as receiving pembrolizumab plus chemotherapy or chemotherapy alone. Temporal uptake trends and time from diagnosis to initiation were described. Multivariable logistic regression identified independent predictors of pembrolizumab receipt, reported as odds ratios (OR) with 95% confidence intervals.
RESULTS: A total of 4,438 early-stage TNBC patients were included, of whom 3,606 (81%) received pembrolizumab plus chemotherapy and 832 (19%) received chemotherapy alone. Initiation was right skewed with peaks at 0, 7, 14, and 21 days post-diagnosis. Pembrolizumab receipt increased with each successive year of diagnosis (OR: 1.12 (1.05-1.19); p<0.001). Patients with Stage III disease had higher odds of pembrolizumab receipt compared with Stage II (OR: 1.84 (1.56-2.17); p<0.001). Increasing age at diagnosis was associated with lower odds of pembrolizumab receipt (OR: 0.98 (0.97-0.98); p<0.001). Patients with Grade 1/2 tumors had lower odds of receipt compared to those with Grade 3 tumors (OR: 0.79 (0.65-0.97); p=0.024). A pre-existing autoimmune diagnosis (OR: 0.81 (0.67-0.98); p=0.031) and higher area-level socioeconomic vulnerability (OR: 0.67 (0.51-0.90); p=0.007) were independently associated with lower odds of receipt. No significant associations were found between pembrolizumab receipt and race/ethnicity, state of residence, rurality, BMI, or comorbidity burden.
CONCLUSIONS: Clinical and tumor characteristics were the primary determinants of pembrolizumab receipt in early-stage TNBC, consistent with guideline-based prescribing. However, greater area-level socioeconomic vulnerability independently predicted lower pembrolizumab receipt, suggesting that access barriers persist even for guideline-recommended therapy.
Conference/Value in Health Info
2026-11, ISPOR Europe 2026, Vienna, Austria
Value in Health, Volume 29, Issue 12S
Code
HSD114
Topic
Epidemiology & Public Health, Health Service Delivery & Process of Care, Real World Data & Information Systems
Disease
Oncology