4-year survival in randomised phase II (POPLAR) and phase III (OAK) studies of atezolizumab (atezo) vs docetaxel (doc) in pre-treated NSCLC
Mazieres J, Rittmeyer A, Gadgeel SM, Hida T, Gandara D, Cortinovis D, Barlesi F, Yu W, Matheny C, Ballinger M, and Park K. 4-year survival in randomised phase II (POPLAR) and phase III (OAK) studies of atezolizumab (atezo) vs docetaxel (doc) in pre-treated NSCLC. Annals of Oncology 2020; 31:S821-S822.
Annals of Oncology
Background: Atezo (anti–PD-L1) showed overall survival (OS) benefit over doc in the phase II (POPLAR; N=287) and phase III (OAK; N=1225) studies in patients (pts) with advanced NSCLC. 4-year survival analysis from both studies is reported for the first time. Methods: In both studies, pts were randomised 1:1 to receive atezo (1200 mg) or doc (75 mg/m2) IV Q3W; PD-L1 expression was assessed by the Ventana SP142 assay on tumour cells (TC) and tumour-infiltrating immune cells (IC); landmark OS was estimated by the Kaplan-Meier method. Results: The minimum follow-up was 53 (POPLAR) and 45 (OAK) mo − an additional 17 and 19 mo follow-up, respectively, from prior reports. 4-year survival rates with atezo vs doc were 14.8% vs 8.1% and 15.5% vs 8.7% in POPLAR and OAK, respectively. The long-term OS benefit of atezo vs doc was seen across histology and PD-L1 expression subgroups. Of pts in the atezo arms who lived ≥4 years in POPLAR (N=15) and OAK (N=43), 40% and 23% were in the PD-L1–high (TC3 or IC3) subgroup, 33% and 37% were in the PD-L1–negative (TC0 and IC0) subgroup, and 87% and 88% had non-squamous histology, respectively. Among 4-year survivors in the doc arms, 2/4 (50%) and 17/26 (65%) received subsequent immunotherapy in POPLAR and OAK, respectively, vs 3/15 (20%) and 10/43 (23%) in the atezo arms. Fewer Grade 3-4 treatment (tx)-related adverse events (AEs) and AEs leading to tx withdrawal occurred in the atezo vs doc arms in both studies. Conclusions: 4-year OS rates favoured atezo vs doc regardless of histology and PD-L1 expression in both studies, despite a high rate of subsequent immunotherapy in the doc arm. The PD-L1–high subgroups continued to derive the greatest OS benefit with atezo vs doc; however, the PD-L1–negative subgroups also sustained an improved long-term OS benefit with atezo vs doc. Most pts in the doc arms received subsequent immunotherapy. Atezo tx was well tolerated, and safety was consistent with prior reports. Clinical trial identification: NCT01903993 (POPLAR), NCT02008227 (OAK).