Counseling Patients on Biomarkers and Cross-Trial Comparisons

Ritu Salani, MD, MBA, of the David Geffen School of Medicine at UCLA, and Rachel N. Grisham, MD, of Memorial Sloan Kettering Cancer Center, discuss how to set expectations when a patient with platinum-resistant ovarian cancer tests positive for a biomarker. Grisham admits that targeted therapy can sound like a guarantee, when most patients do not achieve a confirmed response; a positive biomarker means the drug is more likely to help, not certain to. Relacorilant acts on the glucocorticoid receptor, which more than 95% of ovarian cancers express, so no testing is needed. Salani explains the biologic rationale and stresses monitoring for response. On cross-trial comparisons, Grisham says every clinician makes them but should resist, because the studies used different control arms and populations. She points out that mirvetuximab soravtansine was compared with single-agent chemotherapy and that KEYNOTE-B96 allowed up to 2 prior lines while ROSELLA allowed up to 3, and concludes that an overall survival benefit still signals a preferred regimen.