Clinical activity, safety and predictive biomarkers results from a phase Ia atezolizumab (atezo) trial in extensive-stage small cell lung cancer (ES-SCLC)

Abstract

Methods: ES-SCLC pts received atezo IV q3w at 15 mg/kg or 1200 mg as part of a Ph Ia study (NCT01375842). Due to protocol amendments the first 5 pts were PD-L1 selected and the subsequent 12 were not PD-L1 selected. Initially treatment was to last up to 1 y though retreatment at PD was allowed. Later pts were treated until loss of clinical benefit. RECIST v1.1 and irRC assessments were used. PD-L1 expression was centrally evaluated using the VENTANA SP142 IHC assay. Teffector (Teff) gene signature (CD8A, GZMA, GZMB, EOMES, CXCL9, CXCL10, TBX21) and PD-L1 mRNA was measured (iChip).