Serial Monitoring of Circulating Tumor DNA by Next-Generation Gene Sequencing as a Biomarker of Response and Survival in Patients With Advanced NSCLC Receiving Pembrolizumab-Based Therapy. (2021)

• Record Type: Journal Article
• Authors: Thompson, Jeffrey C.; Carpenter, Erica L.; Silva, Benjamin A.; Rosenstein, Jamie; Chien, Austin L.; Quinn, Katie; Espenschied, Carin R.; Mak, Allysia; Kiedrowski, Lesli A.; Lefterova, Martina; Nagy, Rebecca J.; Katz, Sharyn I.; Yee, Stephanie S.; Black, Taylor A.; Singh, Aditi P.; Ciunci, Christine A.; Bauml, Joshua M.; Cohen, Roger B.; Langer, Corey J.; Aggarwal, Charu
• Is Part Of: JCO precision oncology. Volume 5(2021)
• Publication Date: 2021
• Subjects: Precision Medicine; Neoplasms; Pharmacogenetics; Molecular Targeted Therapy; Personalized medicine; Oncology; Pharmacogenomics; Periodical; Periodicals; 616.994
• DOI: 10.1200/PO.20.00321
• Languages: English
• ISSNs: 2473-4284

Abstract

Abstract : PURPOSE: Although the majority of patients with metastatic non–small-cell lung cancer (mNSCLC) lacking a detectable targetable mutation will receive pembrolizumab-based therapy in the frontline setting, predicting which patients will experience a durable clinical benefit (DCB) remains challenging. MATERIALS AND METHODS: Patients with mNSCLC receiving pembrolizumab monotherapy or in combination with chemotherapy underwent a 74-gene next-generation sequencing panel on blood samples obtained at baseline and at 9 weeks. The change in circulating tumor DNA levels on-therapy (molecular response) was quantified using a ratio calculation with response defined by a > 50% decrease in mean variant allele fraction. Patient response was assessed using RECIST 1.1; DCB was defined as complete or partial response or stable disease that lasted > 6 months. Progression-free survival and overall survival were recorded. RESULTS: Among 67 patients, 51 (76.1%) had > 1 variant detected at a variant allele fraction > 0.3% and thus were eligible for calculation of molecular response from paired baseline and 9-week samples. Molecular response values were significantly lower in patients with an objective radiologic response (log mean 1.25% v 27.7%, P < .001). Patients achieving a DCB had significantly lower molecular response values compared to patients with no durable benefit (log mean 3.5% v 49.4%, P < .001). Molecular responders had significantly longer progression-free survival (hazard ratio, 0.25; 95% CI, 0.13 to 0.50) and overall survival (hazard ratio, 0.27; 95% CI, 0.12 to 0.64) compared with molecular nonresponders. CONCLUSION: Molecular response assessment using circulating tumor DNA may serve as a noninvasive, on-therapy predictor of response to pembrolizumab-based therapy in addition to standard of care imaging in mNSCLC. This strategy requires validation in independent prospective studies.