Atezolizumab meets its primary endpoint of overall survival for patients with resected non-small cell lung cancer across most subgroups.
Atezolizumab produced an overall survival (OS) trend for the programmed death-ligand 1 (PD-L1) TC > 1% in patients with stage II-IIIA non-small cell lung cancer (NSCLC)at the interim analysis of the IMpower010 trial. This was not the case for all intent-to-treat (ITT) patients, nor all the randomized stage II or stage IIIA patients.
The primary endpoint was disease-free survival tested in 3 populations: PD-L1 TC ≥1% stage II-IIIA, a randomized stage II-IIIA group, and the ITT population (stage IB-IIIA). The secondary endpoints included OS in the ITT population, and safety outcomes.
At the interim analysis, those with stage II-III NSCLC and tumors of PD-L1 TC≥ 50% experienced the highest magnitude of OS. The researchers presented data on OS and OS with 13 months of follow-up.
“With an event to patient ratio of 25% in the ITT population, the OS data are not mature, but are of clinical interest in this curative setting,” said Enriqueta Felip, Vall d’Hebron University Hospital, Vall d’Hebron Institute of Oncology, Barcelona, Spain, in a press release.
In past analyses of Impower010, patients taking adjuvant atezolizumab experienced significant disease-free survival. The drug was compared to patients with resected NSCLC who were treated with the best supportive care, platinum-based chemotherapy.
Atezolizumab was consequently approved as an adjuvant treatment after patients with PD-L1 tumor cell (TC) ≥1% stage II-IIIA NSCLC were treated with platinum-based chemotherapy in the United States, China, and other countries. It was also approved to treat patients with PD-L1 TC ≥50% stage II-IIIA NSCLC in the European Union.
In the IMpower010 trial, eligible patients (completely resected stage IB [tumors ≥4 cm]-IIIA NSCLC) took 1 to 4 rounds of 21-day cycles of cisplatin-based doublet chemotherapy. Patients were then randomized 1:1—either taking 1200 mg of atezolizumab once every 3 weeks for 16 cycles or the best supportive chemotherapy care.
In April 2022, the PD-L1 TC ≥1% stage II-IIIA population experienced an OS trend that favored atezolizumab as a treatment.
Grade 3-4 adverse events occurred in 22% of atezolizumab participants and 11.5% of patients treated with supportive care. Due to this effect, 18.2% of atezolizumab participants quit the treatment.
“This OS analysis shows a promising trend in favor of atezolizumab over BSC in the PD-L1 TC ≥1%, stage II–IIIA population and a clinically meaningful improvement in the PD-L1 TC ≥50%, stage II–IIIA population, with the OS improvements observed across most subgroups. No separation was observed for the ITT population or the all-randomized, stage II–IIIA populations, and we will continue to follow patients in this study as data mature,” Felip said in a press release.
Felip added that researchers will continue to analyze final disease-free survival and further OS analyses in the IMpower010 trial. The research was presented at the IASLC World Conference on Lung Cancer 2022 in Vienna.
IMPower010: Overall survival interim analysis of a Phase III study of atezolizumab vs best supportive care in resected NSCLC. EurekAlert! Aug 8, 2022. Accessed Aug 12, 2022. https://www.eurekalert.org/news-releases/960737