Circulating tumor DNA after induction therapy. Patients (n = 47) who responded to induction therapy and proceeded to part C of therapy (maintenance or observation) were included. Serum collected at protocol-defined time points was analyzed blinded to clinical outcomes for the detection of ctDNA (red circle) or absence of detectable ctDNA (green circle). Six patients (blue shade and above bold line) had no detectable ctDNA at end of induction therapy (EOT) and were without radiologic progression at the time of data cutoff. Thirty-four patients (below bold line and above dotted line) had no detectable ctDNA at EOT and were monitored until radiologic progression (square). Seven patients (below dotted line) had detectable ctDNA at EOT and were monitored until radiologic progression. Twenty-eight patients (red shade) progressed and had ctDNA positivity at the time of or before progression, whereas 13 patients (green shade) progressed with no prior detectable ctDNA. 1C, end of the first cycle of induction therapy; 2C, end of the second cycle of induction therapy.