Treatment with the cyclin dependent kinase (CDK) 4/6 inhibitor palbociclib achieves a clinically meaningful improvement in overall survival in patients with hormone receptor positive (HR+) human epidermal growth factor receptor-2 negative (HER2-) advanced breast cancer that has relapsed or progressed on hormonal therapy, according to the final analysis of overall survival results from the PALOMA-3 study reported at ESMO 2018 (1).
Treatment with the cyclin dependent kinase (CDK) 4/6 inhibitor palbociclib achieves a clinically meaningful improvement in overall survival in patients with hormone receptor positive (HR+) human epidermal growth factor receptor-2 negative (HER2-) advanced breast cancer that has relapsed or progressed on hormonal therapy, according to the final analysis of overall survival results from the PALOMA-3 study reported at ESMO 2018 (1).
Most patients with HR+ breast cancer become resistant to hormonal therapies over time and inhibiting CDK4/6 has been identified as a target for overcoming or delaying resistance to hormonal therapy in advanced HR+/HER2-breast cancer. The prospective, randomised phase 3 PALOMA-3 trial showed that the first-in-class CDK 4/6 inhibitor palbociclib in combination with fulvestrant significantly improved progression-free survival (PFS) in 521 women with HR+/HER2- metastatic breast cancer that had progressed on previous hormonal therapy (2).
The new analysis assessed overall survival (OS), a key secondary endpoint of PALOMA-3, after a median follow-up of 44.8 months in 521 patients with HR+/HER2- advanced breast cancer. The patients had relapsed or progressed on prior endocrine therapy before being randomised to palbociclib (125mg/day orally, schedule 3/1) plus fulvestrant (500mg per standard of care) or placebo plus fulvestrant. Researchers carried out the OS analysis when approximately 60% (n≈310) of the 521 patients in the study had died.
Results showed that median overall survival improved by 6.9 months with palbociclib plus fulvestrant (median OS 34.9 months, 95% confidence interval [CI] 28.8-40.0) compared to placebo plus fulvestrant (median OS 28.0 months, 95% CI 23.6-34.6, p=0.043).
Read more at European Society for Medical Oncology
Image: This is Massimo Cristofanilli, Professor of Medicine, Robert H. Lurie Comprehensive Cancer Center of Northwestern University, Feinberg School of Medicine, Chicago, USA, and study author. (Credit: © European Society for Medical Oncology)
