The B-IO Study - Unravelling tumour response and resistance to combined chemotherapy and PD-L1 inhibition with minimal invasive techniques in patients with advanced NSCLC with targetable disease

Chemo-immunotherapy has become the standard first-line treatment for metastatic non-small cell lung cancer (NSCLC); however, reliable biomarkers to guide patient selection and predict treatment response are still lacking. In the B-IO Study, we aim to predict response to chemo-immunotherapy in 73 stage IV NSCLC patients with known driver mutations who progressed after tyrosine kinase inhibitor treatment. We focus on personalized monitoring of therapy response to chemo-immunotherapy using ddPCR-based ctDNA analysis. Serial plasma samples were collected during treatment and analysed by plasma-based next-generation sequencing and patient-specific digital droplet PCR. At baseline, both tumour- (Roche AVENIO CGP) and ctDNA profiling with Roche AVENIO ctDNA Expanded and Surveillance v2 NGS panels were performed to identify tumor-specific mutations, which were then used to design patient- specific Bio-Rad ddPCR assays. Experience with multicolor-ddPCR analysis using tumour- and/or plasma-baseline selected mutations will be presented.