LAUSR

e14576Background: Anti-PD1/PDL1 antibodies (mAbs) have been shown to increase overall survival (OS) compared to standard of care (SOC) in solid tumors (mainly melanoma and lung cancer). Despite the efficacy in OS, a significant proportion of patients (pts) will have progressive disease (PD) as best response. Therefore, we have conducted a meta-analysis to study the rates of response comparing these novel antibodies with SOC (chemotherapy or targeted therapy). Methods: We conducted a search of the published RCT in MEDLINE and EMBASE analyzing anti-PD1/PDL1mAbs monotherapy compared to SOC. All studies used RECIST v1.1. Relative risk (RR) with 95% confidence interval (CI) of response rates between groups was estimated. Clinical heterogeneity was explored via subgroup analyses for location of primary tumor, number of previous treatment lines and selected population by PDL1 expression. Results: Eleven studies accounting for 6,396 pts were included (anti-PD1/PDL1 mAbs: 3,333 pts; SOC: 3,063 pts[2,637 pts: chemo...