Survival Not Better With Onartuzumab Plus Erlotinib for MET-Positive NSCLC
The addition of onartuzumab to erlotinib therapy may not extend survival.
In patients with locally advanced or metastatic MET-positive non-small cell lung cancer (NSCLC), the addition of onartuzumab to erlotinib did not improve overall survival compared with erlotinib alone, a study published in the Journal of Clinical Oncology has shown.1
To evaluate the efficacy and safety of onartuzumab in patients with advanced NSCLC selected by MET immunohistochemistry, investigators designed the multicenter, double-blind phase 3 METLung trial (ClinicalTrials.gov Identifier: NCT01456325).
For the study, researchers enrolled 499 patients who experienced disease progression after treatment with a platinum-based chemotherapy regimen. Participants were randomly assigned 1:1 to receive onartuzumab 15 mg/kg intravenously on day 1 of each 21-day cycle plus erlotinib 150 mg orally daily or erlotinib plus placebo.
Results showed that 8.4% of patients who received onartuzumab plus erlotinib achieved a response vs 9.6% of those given erlotinib plus placebo.
There was no significant difference in overall survival between the 2 arms (hazard ratio [HR], 1.27; 95% CI, 0.98-1.65; P =.067). Median overall survival was 6.8 months with erlotinib plus onartuzumab vs 9.1 months with erlotinib alone.
Similarly, exploratory analyses using MET fluorescence in situ hybridization (FISH) status and gene expression demonstrated no benefit for onartuzumab, and researchers observed a trend toward shorter survival with onartuzumab therapy in patients with EGFR mutations (HR, 4.68; 95% CI, 0.97-22.63).
Researchers also found no significant difference in median progression-free survival between the 2 groups (HR, 0.99; 95% CI, 0.81-1.20; P =.92); median progression-free survival was 2.7 months and 2.6 months with onartuzumab and placebo, respectively.
Grade 3 to 5 adverse events occurred in 56.0% of patients given immunotherapy and 51.2% of those who received placebo. Investigators observed serious adverse events in 33.9% and 30.7% of onartuzumab-treated and placebo-treated patients, respectively.
1. Spigel DR, Edelman MJ, O'Byrne K, et al. Results from the phase III randomized trial of onartuzumab plus erlotinib versus erlotinib in previously treated stage IIIB or IV non-small-cell lung cancer: METLung. 2016 Dec 12. doi: 10.1200/JCO.2016.69.2160. [Epub ahead of print]