Ribociclib reduces early breast cancer death risk by 20% in 6-year study

Results from the Phase III Natalee study, presented at the 2026 European Society for Medical Oncology (ESMO) Congress in Madrid, demonstrate that ribociclib, when used in combination with endocrine therapy, reduces the risk of death by approximately 20% (19.1%) in patients with early-stage HR+/HER2- breast cancer.

The study focused on high-risk patients in stages II and III, including those with node-negative disease and those with lymph node involvement. Data shows that the absolute benefit in invasive disease-free survival (iDFS) increased from 4.1% at five years to 5.3% at six years. Similarly, the absolute difference in overall survival increased from 1.2% at five years to 2.1% at six years.

At the time of analysis, patients had a median period of 38 months since discontinuing the CDK4/6 inhibitor, having completed the five-year endocrine therapy protocol. Experts noted that these findings reinforce the long-term value of combining ribociclib with endocrine therapy for this broad patient population.