Guardant Health Inc. has announced new data from a clinical validation study demonstrating the effectiveness of its Guardant Reveal® blood test in monitoring chemotherapy response in patients with advanced solid tumors. The results, published in the Journal of Liquid Biopsy, show that the tissue-free, methylation-based ctDNA tumor fraction signal detected by the test correlates strongly with patient outcomes. Decreases in tumor fraction signal after starting chemotherapy were associated with longer treatment duration and increased survival rates, while increases in the signal identified disease progression up to 18 months earlier than standard clinical methods, with a median lead time of 2.3 months. The study provides real-world evidence supporting the use of Guardant Reveal as a non-invasive tool for pan-cancer chemotherapy monitoring.