FDA Approves Atezolizumab for Extensive-Stage Small Cell Lung Cancer
On March 18, 2019, the U.S. Food and Drug Administration (FDA) approved atezolizumab (Tecentriq) in combination with carboplatin and etoposide for the first-line treatment of adult patients with extensive-stage small cell lung cancer.
IMpower133
Approval was based on the IMpower133 study, a randomized (1:1), multicenter, double-blind, placebo-controlled trial in 403 patients with extensive-stage small cell lung cancer who received no prior chemotherapy for extensive stage disease and had ECOG performance status 0 or 1. Patients were randomized to one of the following:
- Atezolizumab 1,200 mg and carboplatin area under curve (AUC) 5 mg/mL/min on day 1 and etoposide 100 mg/m2 intravenously on days 1, 2, and 3 of each 21-day cycle for a maximum of 4 cycles, followed by atezolizumab 1,200 mg once every 3 weeks until disease progression or unacceptable toxicity;
- Placebo and carboplatin AUC 5 mg/mL/min on day 1 and etoposide 100 mg/m2 intravenously on days 1, 2, and 3 of each 21-day cycle for a maximum of 4 cycles, followed by placebo once every 3 weeks until disease progression or unacceptable toxicity.
Major efficacy outcome measures were overall survival (OS) and progression-free survival (PFS) as assessed by investigator per RECIST 1.1 in the intent-to-treat population. Median OS was 12.3 months (10.8–15.9) for patients receiving atezolizumab with chemotherapy and 10.3 months (9.3–11.3) for those receiving placebo with chemotherapy (hazard ratio [HR] = 0.70; 95% confidence interval [CI] = 0.54–0.91; P = .0069). Median PFS was 5.2 months (4.4–5.6) compared with 4.3 months (4.2–4.5) in the atezolizumab and placebo arms, respectively (HR 0.77; CI = 0.62–0.96; P = .0170).
The most common adverse reactions reported in ≥ 20% of patients who received atezolizumab in IMpower133 were fatigue/asthenia, nausea, alopecia, constipation, and decreased appetite.
The recommended atezolizumab dose for patients with extensive-stage small cell lung cancer is 1,200 mg intravenously over 60 minutes every 3 weeks. When administered on the same day, atezolizumab should be administered prior to chemotherapy. If the first infusion is tolerated, all subsequent infusions may be delivered over 30 minutes.
View the full prescribing information for atezolizumab.
The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.
