Healthcare Resource Utilization and Real-World Disease Burden Among Patients With PD-L1-Positive Metastatic Triple-Negative Breast Cancer in the First-Line Setting

Objectives
To describe healthcare resource utilization (HCRU) and disease burden in patients with PD-L1-positive (PD-L1+) metastatic triple-negative breast cancer (mTNBC) in the first-line (1L) setting.

Methods
This retrospective cohort study analyzed de-identified mTNBC patient records linked to claims using the Tempus Lens Platform (Tempus AI, Inc., Chicago, IL). Adults with PD-L1+ mTNBC initiating 1L therapy between January 2018 and June 2024 (index date) were included. Patients were followed from index to death, last record, or study end (June 2025), with ≥3 months follow-up required if alive. Treatment patterns were described. Real-world overall survival (rwOS), progression-free survival (rwPFS), time to next treatment or death (rwTTNTD), and time on treatment (rwToT) were estimated using Kaplan-Meier methods with risk-set adjustment for left truncation. All-cause HCRU was reported per-patient-per-month (PPPM) in a subset with continuous claims enrollment.

Results
161 patients with PD-L1+ mTNBC were included (mean age, 57.8 years; 82 [51%] had recurrent disease, and 9 [11%] received pembrolizumab in the early setting; median follow-up, 19.3 months). Of 161 patients who received 1L treatment, 24 (15%) received chemotherapy monotherapy, 21 (13%) chemotherapy combinations, and 113 (70%) immunotherapy-based regimens. Among 106 patients who received subsequent lines of therapy, sacituzumab govitecan was used in 2L for 25 (24%) patients and in 3L for 27 (25%) patients. Of patients who received 1L treatment, median rwOS was 22.4 months, rwPFS was 6.4 months, rwTTNTD was 9.2 months, and rwToT was 3.8 months. Among 72 patients eligible for all-cause HCRU analyses, there were 0.51 hospitalizations, 0.11 emergency room visits, 2.22 outpatient medical visits, and 2.99 office visits PPPM.

Conclusions
Patients with PD-L1+ mTNBC experienced suboptimal outcomes and high HCRU, characterized by routine care and high utilization of hospital-administered immunotherapy, underscoring a substantial unmet need in this population.