Ex vivo drug sensitivity testing predicts treatment outcomes in advanced ovarian cancer

Effective management of advanced epithelial ovarian cancer (EOC) is challenging, with most patients relapsing despite standard therapies, highlighting the need for personalized treatment. Functional ex vivo drug testing enables matching patients to effective therapies based on drug sensitivity. We present DRUGSENS, a scalable, clinically adaptable ex vivo screening platform that quantitatively assesses single-cell, on-target drug effects in cell lines and patient-derived samples. DRUGSENS offers high-resolution analysis of responses to single agents and relevant drug combinations, guiding personalized treatment across tumor types. The semi-automated assay integrates immunofluorescence-based confocal imaging with computational analysis using QuPath, Fiji, and a dedicated R package. We profiled 21 samples from 17 patients in chemotherapy-naive and relapsed states, achieving 100% culture success and delivering results within 10 days. Most samples showed limited sensitivity to multiple agents, indicating multidrug resistance. Notably, ex vivo drug responses correlated significantly with progression-free and overall survival. DRUGSENS supports rapid, clinically relevant functional profiling in EOC, providing a valuable tool to inform treatment recommendations and prioritize drugs for clinical application.