Treatment Selection and Biomarker Testing at Platinum Resistance

Rachel N. Grisham, MD, of Memorial Sloan Kettering Cancer Center, and Ritu Salani, MD, MBA, of the David Geffen School of Medicine at UCLA, walk through how they choose a first regimen when a patient with ovarian cancer becomes platinum resistant. Grisham explains that she starts with how the patient tolerated prior therapy, whether low blood counts or neuropathy were the main problem, and what matters most to her, then favors the three regimens shown to improve overall survival: pembrolizumab with weekly paclitaxel with or without bevacizumab, single-agent mirvetuximab soravtansine, and relacorilant with nab-paclitaxel. Salani reviews the biomarker requirements: folate receptor alpha (FRα) expression of 75% or more at 2+ to 3+ intensity for mirvetuximab and a PD-L1 combined positive score of 1 or greater for pembrolizumab. Grisham orders FRα, PD-L1, and HER2 testing at diagnosis and retests at recurrence. For patients positive for every biomarker, she weighs side effects and schedule, including eye care and pneumonitis risk with mirvetuximab and G-CSF with relacorilant plus nab-paclitaxel.