OBJECTIVES: Examine HCRU and costs among 1L treated patients with non-squamous (Cohort1) and squamous (Cohort2) mNSCLC who initiated 5th cycle.

METHODS: Data from SEER and Medicare linked claims was used for analysis of ≥66-year-old patients diagnosed with mNSCLC (stage IV) between 2007-2019. Continuously enrolled (i.e. ≥ 6-month post NSCLC diagnosis) patients who completed ≥4 induction cycles with 1L pembrolizumab combination-therapy with cisplatin/carboplatin plus pemetrexed (Cohort 1) or paclitaxel/nab-paclitaxel (Cohort 2); and initiated the 5^th treatment cycle (i.e., index date) were included. Per patient per month (PPPM) all-cause, NSCLC-related, adverse event (AE)-associated, and other-cause HCRU and costs were estimated for different medical services (i.e., inpatient admission, outpatient, emergency, and skilled-nursing), and pharmacy visits. AEs of interest were identified through claims with both primary and secondary diagnostic codes. Mean terminal-care costs were calculated as an average of all costs incurred 30-days before death.

RESULTS: In Cohort 1(n=500), mean age was 75.8 years, 44.8% males, and 87.6% whites. In Cohort 2 (n=135), mean age was 75.7 years, 63.0% males, and 85.9% whites. All-cause PPPM outpatient visits were higher than inpatient admissions, skilled-nursing, and emergency visits (Cohort 1 =1.83 vs 0.15, 0.01, 0.19 and Cohort 2 =1.79 vs. 0.21, 0.05, 0.3, respectively). For NSCLC-related HCRU, outpatient visits were also greater than inpatient admissions, skilled-nursing, and emergency visits (Cohort 1 =0.74 vs. 0.14, 0.01, 0.12; Cohort 2 =0.75 vs. 0.19, 0.03, 0.18). Total all-cause PPPM medical services costs were $8,952 (Cohort 1) and $10,951 (Cohort 2). Total AE-associated PPPM medical services costs in cohorts 1 and 2 were $3,921 and $5,523, respectively; greater costs were incurred due to inpatient admissions (Cohort 1: $1,991, Cohort 2: $3,365). Mean terminal-care costs were $18,693 (Cohort 1) and $20,004 (Cohort 2), respectively.

CONCLUSIONS: First-line treated patients with mNSCLC who initiated a 5^th cycle bear substantial economic burden.