Effect of ribociclib Plus fulvestrant on overall survival in the treatment of advanced breast cancer - updated MONALEESA-3 results

The results of the treatment of ER-positive/HER2-negative advanced breast cancer have been improved in the last few years due to the use of CDK4/6 inhibitors combined with endocrine therapy. Ribociclib with fulvestrant significantly prolonged progression-free survival and overall survival in the phase-III MONALEESA-3 trial. The newest update of the trial (after 56.3 months of observation) showed significant improvement in overall survival in the experimental arm for more than ayear: mOS was 53.7 months in the ribociclib plus fulvestrant arm and 41.5 months in the placebo plus fulvestrant arm (risk reduction of 27%). Subgroup analysis confirmed the efficacy of the treatment in both the first and second lines of treatment. The study also showed that adding ribociclib to the endocrine treatment prolongs the median time to chemotherapy. No new toxicities were observed in longer observation.