“For the first time, we are seeing that an immunotherapy is effective when used to treat early-stage lung cancer.

The IMpower010 trial demonstrates that, for certain patients, atezolizumab can delay progression to advanced disease, and perhaps even the need for more aggressive therapy.

This could be an important advance in our understanding of immunotherapy and a step forward for many patients with lung cancer” said ASCO Chief Medical Officer and Executive Vice President Julie R. Gralow, MD, FACP, FASCO.

Treatment with the immunotherapy atezolizumab extended disease-free survival (DFS) in patients with resected, early-stage non-small cell lung cancer (NSCLC), particularly those positive for the immune checkpoint protein PD-L1, according to new research to be presented at the 2021 American Society of Clinical Oncology (ASCO) Annual Meeting.

The findings open the door to delaying recurrence even longer for patients with early-stage disease.

While immunotherapies have demonstrated success in improving survival in patients with advanced NSCLC, IMpower010 is the first phase III study to find that adjuvant immunotherapy can significantly extend DFS in patients with resected stage II-IIIA NSCLC.

Atezolizumab is a type of immunotherapy that belongs to a class of therapies known as checkpoint inhibitors, that improves immune system response to tumour cells by blocking a protein (PD-L1) on the tumour cell surface.

Approximately half of people diagnosed with early-stage NSCLC express PD-L1 on their tumour cells.

Patients who received atezolizumab had a 34% reduction in the risk of disease recurrence or death compared with best supportive care in patients with stage II-IIIA and levels of the immune checkpoint protein PD-L1 of 1% or greater.

In this group, the median DFS has not yet been reached at data cut-off, while the median DFS for best supportive care was 35.3 months.

Among all patients with stage II-IIIA NSCLC, those who received atezolizumab had a 21% reduction in the risk of disease recurrence or death versus best supportive care.

DFS with atezolizumab was 42.3 months compared with 35.3 months for best supportive care. The DFS for atezolizumab compared with best supportive care in the entire cohort of patients with stage IB-IIIA disease did not reach significance at this interim DFS analysis.

Overall survival data (OS) were immature.

Adverse events of any grade occurred in 92.7% and 70.7% in the atezolizumab and best supportive care groups, respectively. More grade 3/4 adverse events were seen in those that received immunotherapy, compared to best supportive care – 21.8% and 11.5%, respectively.

Nearly 20% of those in the atezolizumab arm experienced adverse side effects that caused them to discontinue treatment.

“Though surgery can cure some patients with early-stage lung cancer, disease recurrence is still very common.

Until this trial, the only treatment that was known to help reduce that risk for most patients was chemotherapy (or osimertinib for the small group of patients with tumours with an EGFR mutation),” said lead author Heather Wakelee, MD, a thoracic specialist and Professor of Medicine and Chief of the Division of Oncology at the Stanford University Medical Center.

“These data show that personalised medicine with atezolizumab can reduce the chance of NSCLC returning after surgery for patients who have a tumour that expresses the biomarker PD-L1.”

A total of 1,280 patients were enrolled.

Following cisplatin-based chemotherapy, 1,005 patients were randomised 1:1 to receive atezolizumab or best supportive care.

The primary endpoint, DFS, was assessed in patients with stage II-IIIA disease with levels of PD-L1 of at least 1%; all patients with stage II-IIIA disease; and patients with stage IB-IIIA NSCLC. OS was the secondary endpoint.

Safety was assessed in all patients who received at least one dose of atezolizumab, or who had at least one post-baseline safety assessment, if randomized to the best supportive care arm.

The trial is ongoing, and median DFS with atezolizumab has not yet been reached. OS for patients is still being followed.

Source: ASCO