FDA Approves Firstline Lung Cancer Combination

The U.S. Food and Drug Administration (FDA) approved atezolizumab in combination with carboplatin and etoposide for firstline treatment of adults with extensive-stage small cell lung cancer.

The decision was based on results from the multicenter, double-blinded, randomized, placebo-controlled, phase III IMpower133 study, which enrolled 403 patients who were randomized 1:1 to receive atezolizumab in combination with carboplatin and etoposide (n=201) or placebo in combination with carboplatin and etoposide (control arm; n=202).

Improved Survival With Atezolizumab

The findings demonstrated that atezolizumab plus chemotherapy improved median overall survival (OS) compared with chemotherapy alone (12.3 vs. 10.3 months; hazard ratio [HR] = 0.70, 95% CI, 0.54-0.91; P=0.0069). Atezolizumab plus chemotherapy also significantly increased progression-free survival (5.2 vs. 4.3 months; HR=0.77; 95% CI, 0.62-0.96; P=0.017).

The one-year OS rate was 51.7% in the atezolizumab group and 38.2% in the placebo group, while the objective response rate was 60% and 64%, respectively. The median duration of response was longer in the atezolizumab group (4.2 months vs. 3.9 months).

Safety Profile of Atezolizumab

Adverse events (AEs) associated with the atezolizumab cohort were consistent with the known safety profile of the drug. Grade 3/4 AEs were reported in 56.6% of the atezolizumab group and 56.1% of the control group. Serious AEs occurred in 37% of patients in the atezolizumab cohort compared with 35% of the chemotherapy alone group. The most common AEs in the atezolizumab group were fatigue/asthenia (39%), nausea (38%), alopecia (37%), decreased appetite (27%), constipation (26%), and vomiting (20%).

Atezolizumab is also FDA-approved in combination with bevacizumab, paclitaxel, and carboplatin for the firstline treatment of adults with metastatic non-squamous non-small cell lung cancer (NSCLC) with no EGFR or ALK genomic tumor aberrations. It is also FDA-approved to treat adults with metastatic NSCLC who experience disease progression during or following platinum-containing chemotherapy.