Int J Cancer. 2020 Sep 1. doi: 10.1002/ijc.33281. Online ahead of print.
In aNSCLC, stopping nivolumab after 12 months (mo) negatively affects outcomes. We performed a world data-based analysis assessing the value of nivolumab continuation and optimal dosing beyond 24mo. Out of 697 consecutive patients with aNSCLC in whom nivolumab was initiated between 2015-2018, 45 patients receiving nivolumab for ≥24mo were selected. These were divided into groups A: nivolumab administered at a dose 3 mg/kg q2 weeks (w)/240 mg q2w/480 mg q4w, n = 25; B: nivolumab re-scheduled to a
non-standard dose 3 mg/kg q3w-q8w, n = 13; C: nivolumab stopped after 24mo, n = 7; (in groups B and C - for reasons other than progressive disease or intolerable toxicity). PFS (RECIST 1.1) and safety (CTCAE, 4.03) were assessed. With median follow-up of 35.6mo [IQR 28.4-41.8], 4%, 31%, 29%, and 30% of patients progressed in groups A, B, C, and B + C, respectively. PFS at 36 months since nivolumab initiation comprised 100%, 67%, 67% and 67%, in groups A, B, C, and B + C, respectively. PFS at 40 months since nivolumab initiation comprised 83%, 67%, 67% and 67%, in groups A, B, C, and B + C, respectively. Allocation to group A vs group B, C, and B + C was associated with HR for PFS-0.20 (95%CI, 0.02-1.77, p-0.15), 0.20 (95%CI, 0.02-2.25, p-0.19), and 0.20 (95%CI, 0.02-1.66, p-0.14), respectively. No differences in newly-occurring or worsening adverse events between the groups were observed. A trend for worse PFS was observed with alternative nivolumab scheduling or quitting 24mo after initiation. Continuing nivolumab at a standard dose until disease progression or intolerable toxicity remains the standard treatment option.