Sequist LV, et al. - Researchers tested seribantumab (a fully human IgG2 monoclonal antibody) plus erlotinib in advanced non-small cell lung cancer (NSCLC), with a focus on the safety and effectiveness of this treatment option. In patients with EGFR wild-type tumors, they evaluated the activity of seribantumab plus erlotinib vs erlotinib alone, as well as if heregulin (HRG) has any predictive ability. Seribantumab + erlotinib (n=85) or erlotinib alone (n=44) was received by the participants, based on random assignment. Core needle biopsy was performed before treatment and archived tumor samples were obtained to support prespecified biomarker analyses. In unselected patients, no improvement in the progression-free survival was achieved with the addition of seribantumab to erlotinib, but patients who might benefit from seribantumab were identified by detectable HRG mRNA levels, as suggested in predefined retrospective exploratory analyses.