A retrospective, non-interventional study of breast cancer patients diagnosed with ER+/HER2 negative, locally advanced or metastatic breast cancer treated with palbociclib in Denmark.

BACKGROUND

The recommended first-line treatment for advanced, ER+/HER2 negative breast cancer is a CDK 4/6 inhibitor in combination with an endocrine backbone. This study investigated the use of palbociclib, as first- or second-line therapy for advanced breast cancer patients in a real-world setting.

MATERIAL AND METHODS

This retrospective, population-based study included all Danish, advanced breast cancer patients with ER+/HER2 negative disease who initiated first- or second-line treatment with palbociclib from January 1

RESULTS

The study included 1054 advanced breast cancer patients with a mean age of 66.8 years. Median OS was 51.7 months (95% CI, 44.9-54.6) for all patients in the first-line setting (

CONCLUSION

In this real-world study, treatment with palbociclib combination therapy met the standards of efficacy set by the phase III trials, PALOMA-2 and PALOMA-3, and the standards set by real-world studies in other countries. The study showed significantly different outcomes in terms of PFS and OS in endocrine sensitive patients comparing AI vs. fulvestrant as endocrine backbone to palbociclib as first-line therapy.