Atezolizumab (PD-L1 mAb) Halves 5-Year Recurrence & Mortality Risk in PD-L1-High Resected NSCLC

Atezolizumab is a monoclonal antibody that targets PD-L1. In the open-label phase III IMpower010 trial (NCT02486718), 1,005 patients with completely resected stage IB–IIIA NSCLC were randomized to receive atezolizumab 1,200 mg every three weeks for 16 cycles or best-supportive care (BSC) after standard platinum chemotherapy. Among stage II–IIIA tumors expressing PD-L1 on ≥1 % of tumour cells (TC), median disease-free survival (mDFS) was 68.5 months with atezolizumab versus 37.3 months with BSC. In the overall stage II–IIIA population, regardless of PD-L1 status, mDFS reached 57.4 months with atezolizumab compared with 40.8 months for BSC after a median 90-month follow-up. For the intent-to-treat cohort, mDFS was 65.6 months versus 47.8 months, yielding a hazard ratio (HR) of 0.85 with a p-value of 0.07—borderline and not crossing the prespecified significance boundary. In the PD-L1 TC ≥ 50 % subgroup (with or without EGFR/ALK alterations), mDFS had not yet been reached for atezolizumab, whereas it was 41.1 months for BSC at the same 90-month follow-up.

At the ≥5-year cut-off, DFS HRs consistently favoured atezolizumab: 0.85 for the ITT population, 0.83 for all stage II–IIIA patients, 0.70 for PD-L1 TC ≥ 1 %, and 0.48 for PD-L1 TC ≥ 50 %. Overall-survival HRs paralleled these results, and no new safety signals emerged with long-term treatment.