Disease-free survival (DFS; time after diagnosis during which a person shows no signs of the disease returning) was not improved when adjuvant (post-surgery) Imfinzi (durvalumab) was given after complete tumor removal and optional chemotherapy versus placebo for patients with EGFR- or ALK-negative non-small cell lung cancer (NSCLC) across PD-L1 positive (protein that helps cancer cells hide from immune system) subgroups, according to results from the phase 3 trial presented at the 2024 European Society of Medical Oncology Congress.
The median DFS in patients with PD-L1 expression of 25% or more in the Imfinzi arm was 69.9 months versus 60.2 months in the placebo arm. The 18-month DFS rate in the Imfinzi arm was 75.1% versus 70.5% in the placebo arm. The 24-month rate was 71.2% versus 68.5% and the 36-month rate was 63.9% versus 62.4%.
The median DFS in patients with PD-L1 expression of 1% or more was 59.9 months in the Imfinzi arm and 60.3 months in the placebo arm. The 18-month DFS rates were 73.4% versus 70.1%; 24-month rates were 68.6% versus 67.0%; and 36-month rates were 60.2% versus 60.1%, in the Imfinzi and placebo arm, respectively.
For patients with NSCLC, regardless of their PD-L1 status, the median DFS was 60 months in the Imfinzi arm and 53.9 months in the placebo arm. The DFS rates at 18 months were 72.1% versus 66.0%; at 24 months, they were 67.4% versus 63.3%; and at 36 months, they were 60.4% versus 56.4%.
“The outcomes of the BR.31 study suggest that the presence of primary disease and associated tumor antigens [unique proteins on cancer cells that the immune system can attack], as in the perioperative approach [the time before, during, and after surgery], may be required for optimal efficacy [in NSCLC],” Glenwood Goss, a professor of medicine in the University of Ottawa Division of Medical Oncology, a chair of the Thoracic Oncology Site Committee and director of Clinical and Translational Research at Ottawa Hospital Cancer Centre, said in a presentation on these data.
Patients with stage 1B to 3A NSCLC who had complete resection (tumor removal), an ECOG performance status of 0 to 1 (patients were limited in strenuous activity but could perform daily tasks) and EGFR-mutated/ALK-positive disease were eligible to enroll. Patients received a platinum doublet followed by surgery and randomization at three weeks or more. Patients were randomly assigned two-to-one to Imfinzi at 20 mg/kg every four weeks for 12 months or matched placebo.
The primary focus was investigator-assessed (examined by a healthcare professional) DFS in patients with PD-L1 expression of 25% or more and EGFR- or ALK-negative disease. Secondary end points included DFS in patients who had PD-L1 expression of 1% or more and EGFR- or ALK-negative disease, all patients with PD-L1 expression of 25% or more, all randomly assigned patients, PD-L1 all comers (all levels of PD-L1 protein) with EGFR- or ALK-negative disease, and all patients with PD-L1 expression of 1% or more; overall survival (the time from the start of treatment when a patient with cancer is still alive); side effects; and quality of life (person's overall well-being, including physical, emotional, social and spiritual aspects).
Overall, 1,827 patients registered, with randomization of 1,415 taking place between February 2015 and March 2020. There was a total of 1,219 patients with EGFR- or ALK-negative disease. Of the 1,415 patients who were randomly assigned, 944 and 471 were assigned to the Imfinzi arm and the placebo arm, respectively. At data cutoff, 67.7% of patients in the Imfinzi arm and 67.5% in the placebo arm were still receiving study treatment.
In the PD-L1 expression of 25% or more group, the median age was 65 years versus 63 years in the Imfinzi versus placebo arms, 61.1% versus 64.6% were male, 47.5% versus 41% were White, and 81.6% versus 79.5% were former smokers. Additionally, the most common histology type was adenocarcinoma in 63% versus 59%, 54.4% versus 50.9% had stage 2 disease and 65.8% versus 64.6% had PD-L1 expression of 50% or more.
In the PD-L1 expression of 1% or more group, the median age was 65 years versus 63 years in the Imfinzi and placebo arms, with 62.5% versus 64.6% being male, 46.1% versus 42.1% were White, and 78.3% versus 77.5% were former smokers. The most common histology type was adenocarcinoma (cancer found in glandular cells located across multiple organs) in 60.8% versus 58.8%, and 44.3% versus 43.3% had PD-L1 expression of 50% or more.
In the PD-L1 all-comers group, the median age was 64 years versus 64 years in each arm, respectively; 64.8% versus 66.8% were male, 46.1% versus 46.5% were White and 78.4% versus 76.5% were formers smokers. The most common histology type was adenocarcinoma in 66.3% versus 60.6%, and 42.5% versus 40.6% had PD-L1 expression of less than 1%.
The safety analysis included all patients who had received at least one dose of treatment. Any kind of side effects occurred in 93.8% in the Imfinzi arm and 92.3% in the placebo arm. Grade 3/4 (severe/life-threatening) side effects occurred in 23.5% versus 19.6%, and side effects leading to death occurred in 0.7% versus 0.2% between either arm. Serious side effects were observed in 18.8% versus 15.4%, and side effects leading to discontinuation occurred in 14% versus 5.1% in the Imfinzi and placebo arms, respectively.
For more news on cancer updates, research and education, don’t forget to subscribe to CURE®’s newsletters here.
