The Study: Springtime is fleeting so the PERSEPHONE trial is jumping the gun with a sneak peak of its results prior to official reporting at ASCO 2018. This is a practical trial out of the UK looking to turn heads without reinventing the wheel. Over 4K women with HER2-positive breast cancer were randomized to the traditional 12 months versus the experimental 6 months of adjuvant trastuzumab. Over two-thirds were estrogen-receptor positive. Cytotoxic chemo was institutional choice, but 90% received an anthracycline and 60% a taxane. After the predefined 500th event needed to perform non-inferiority calculations, disease-free survival was measured as exactly the same in both arms—89% at 4 years—officially meeting non-inferiority thresholds. Overall survival was also reportedly “congruent.” What was significantly different? Cardiac events precluding further therapy, which occured in 4% versus 8% of patients allocated to 6 versus 12 months of trastuzumab. Wow, who could want more? We do, and it’s called 6 months of Ontruzant.
Bottom Line: Half the adjuvant trastuzumab means half the cardiac toxicity without forfeiting disease control in women with HER2-positive breast cancer. | Earl, J Clin Oncol 2018