1135P Adverse event (AE) burden of nivolumab-based immuno-oncology (IO) therapy with/without chemotherapy (chemo) for first-line (1L) advanced non-small cell lung cancer (aNSCLC)

Abstract

Nivolumab + ipilimumab (N + I) alone or with limited chemo (LC; up to 6 weeks [wks]) provide new 1L treatment (tx) options for aNSCLC; but the relative contributions of the different agents to the AE profile over time have not been assessed. Here, we quantified the AE rates and associated costs for N + I, N + I + LC, and N + chemo (C; 12+ wks) over time during tx for 1L aNSCLC. Exposure-adjusted event rates (EAERs) were calculated as the number of occurrences of all-cause grade 3–5 AEs per patient-year (PY), using individual patient data from the CheckMate 227 Parts 1 and 2 and CheckMate 9LA trials (minimum follow-up: 48, 38, and 23 months, respectively). EAERs were estimated for the overall trial period and at 5 pre-specified time periods (wks 0–6, 7–12, 13–24, 25–48, and 49+) to assess the impact of tx on AE burden. AE costs per patient were estimated as the rates of grade 3–5 AEs (with any-grade incidence ≥15%) multiplied by the corresponding unit hospitalization costs for AE management obtained from the 2019 US Healthcare Cost and Utilization Project National Inpatient Sample database. EAERs of all-cause grade 3–5 AEs per PY were lower with N + I (4.8) vs N + I + LC (7.0) and N + C (6.1) at wks 0–6 and lower with N + I (4.0) and N + I + LC (3.1) vs N + C (5.2) at wks 7–12, when chemo was administered; EAERs for the total exposure time period were similar in the N + I (2.6), N + I + LC (2.5), and N + C (2.5) tx groups (Table). EAERs continued to decline in subsequent wks in all 3 tx groups. Overall AE costs were lower with N + I ($6560) and N + I + LC ($7492) vs N + C ($11,731); similar trends were seen per time period.Table: 1135PTime period, wksEAERaAE costb, $N 3 mg/kg Q2W + I 1 mg/kg Q6W n = 576N 360 mg Q3W + I 1 mg/kg Q6W + LC Q3W, up to 2 cycles n = 358N 360 mg Q3W + C Q3W, 4+ cycles n = 547N 3 mg/kg Q2W + I 1 mg/kg Q6W n = 576N 360 mg Q3W + I 1 mg/kg Q6W + LC Q3W, up to 2 cycles n = 358N 360 mg Q3W + C Q3W, 4 + cycles n = 5470–64.87.06.12033315537157–124.03.15.216501157332813–242.52.22.79441080237425–481.71.71.210571423118049+1.51.11.08756761134Overall2.62.52.56560749211,731aPer PY (defined as the total exposure time [time between date of first dose and the earliest among last dose date + 30 days, cutoff date, and date of death] for each patient at risk of AE); bPer patient. 1 cycle = 3 wks; Q2W, every 2 wks; Q3W, every 3 wks; Q6W, every 6 wks. Open table in a new tab aPer PY (defined as the total exposure time [time between date of first dose and the earliest among last dose date + 30 days, cutoff date, and date of death] for each patient at risk of AE); bPer patient. 1 cycle = 3 wks; Q2W, every 2 wks; Q3W, every 3 wks; Q6W, every 6 wks. Higher incidence of AEs and AE costs associated with N + I + LC and N + C vs N + I correlated with the time when chemo was administered during tx; toxicities and costs declined over time after chemo was completed. Results imply an overall lower AE cost burden with 1L N + I compared with IO + chemo-based tx regimens for aNSCLC.