Ontology highlight
ABSTRACT: Purpose
Non-invasive monitoring of circulating tumor DNA (ctDNA) has the potential to be a readily available measure for early prediction of clinical response. Here, we report on early ctDNA changes of KRAS G12C in a Phase 2 trial of adagrasib in patients with advanced, KRAS G12C-mutant lung cancer.Experimental design
We performed serial droplet digital PCR (ddPCR) and plasma NGS on 60 KRAS G12C-mutant patients with lung cancer that participated in cohort A of the KRYSTAL-1 clinical trial. We analyzed the change in ctDNA at 2 specific intervals: Between cycles 1 and 2 and at cycle 4. Changes in ctDNA were compared with clinical and radiographic response.Results
We found that, in general, a maximal response in KRAS G12C ctDNA levels could be observed during the initial approximately 3-week treatment period, well before the first scan at approximately 6 weeks. 35 patients (89.7%) exhibited a decrease in KRAS G12C cfDNA >90% and 33 patients (84.6%) achieved complete clearance by cycle 2. Patients with complete ctDNA clearance at cycle 2 showed an improved objective response rate (ORR) compared with patients with incomplete ctDNA clearance (60.6% vs. 33.3%). Furthermore, complete ctDNA clearance at cycle 4 was associated with an improved overall survival (14.7 vs. 5.4 months) and progression-free survival (HR, 0.3).Conclusions
These results support using early plasma response of KRAS G12C assessed at approximately 3 weeks to anticipate the likelihood of a favorable objective clinical response.
SUBMITTER: Paweletz CP
PROVIDER: S-EPMC10527102 | biostudies-literature | 2023 Aug
REPOSITORIES: biostudies-literature
Paweletz Cloud P CP Heavey Grace A GA Kuang Yanan Y Durlacher Emily E Kheoh Thian T Chao Richard C RC Spira Alexander I AI Leventakos Konstantinos K Johnson Melissa L ML Ou Sai-Hong Ignatius SI Riely Gregory J GJ Anderes Kenna K Yang Wenjing W Christensen James G JG Jänne Pasi A PA
Clinical cancer research : an official journal of the American Association for Cancer Research 20230801 16
<h4>Purpose</h4>Non-invasive monitoring of circulating tumor DNA (ctDNA) has the potential to be a readily available measure for early prediction of clinical response. Here, we report on early ctDNA changes of KRAS G12C in a Phase 2 trial of adagrasib in patients with advanced, KRAS G12C-mutant lung cancer.<h4>Experimental design</h4>We performed serial droplet digital PCR (ddPCR) and plasma NGS on 60 KRAS G12C-mutant patients with lung cancer that participated in cohort A of the KRYSTAL-1 clini ...[more]