Second-line palbociclib and endocrine therapy

PALOMA-3 (NCT01942135) was a double-blind, phase III trial of 521 patients with HER2-negative hormone receptor–positive, advanced breast cancer who had relapsed after or progressed on previous endocrine therapy and were randomly assigned to receive either fulvestrant plus placebo or fulvestrant plus palbociclib. Premenopausal and postmenopausal patients were eligible. Premenopausal patients received goserelin.[5][Level of evidence A3]

PALOMA-3 (NCT01942135) was a double-blind, phase III trial of 521 patients with HER2-negative hormone receptor–positive, advanced breast cancer who had relapsed after or progressed on previous endocrine therapy and were randomly assigned to receive either fulvestrant plus placebo or fulvestrant plus palbociclib. Premenopausal and postmenopausal patients were eligible. Premenopausal patients received goserelin.[5][Level of evidence A3]

The final PFS analysis showed a median PFS of 9.5 months on the palbociclib-fulvestrant arm versus 4.6 months on the placebo-fulvestrant arm (HR, 0.46; 95% CI, 0.36–0.59; P < .0001).[21][Level of evidence A3]

PALOMA-3 (NCT01942135) was a double-blind, phase III trial of 521 patients with HER2-negative hormone receptor–positive, advanced breast cancer who had relapsed after or progressed on previous endocrine therapy and were randomly assigned to receive either fulvestrant plus placebo or fulvestrant plus palbociclib. Premenopausal and postmenopausal patients were eligible. Premenopausal patients received goserelin.[5][Level of evidence A3]

Cytopenias, particularly neutropenia, were much more frequent on the palbociclib-containing arm, but febrile neutropenia was very uncommon (1%) in both groups. Patients receiving palbociclib had more-frequent fatigue, nausea, and headache.

PALOMA-3 (NCT01942135) was a double-blind, phase III trial of 521 patients with HER2-negative hormone receptor–positive, advanced breast cancer who had relapsed after or progressed on previous endocrine therapy and were randomly assigned to receive either fulvestrant plus placebo or fulvestrant plus palbociclib. Premenopausal and postmenopausal patients were eligible. Premenopausal patients received goserelin.[5][Level of evidence A3]

A prespecified analysis of OS was made after 310 patients had died. A 6.9 month difference in median OS favoring the palbociclib-fulvestrant arm (34.9 months vs. 28.0 months) was found, which did not reach statistical significance (HR, 0.81; 95% CI, 0.64–1.03; P = .09).[22]

PALOMA-3 (NCT01942135) was a double-blind, phase III trial of 521 patients with HER2-negative hormone receptor–positive, advanced breast cancer who had relapsed after or progressed on previous endocrine therapy and were randomly assigned to receive either fulvestrant plus placebo or fulvestrant plus palbociclib. Premenopausal and postmenopausal patients were eligible. Premenopausal patients received goserelin.[5][Level of evidence A3]

In a preplanned subgroup analysis, improved OS was observed in patients who had demonstrated sensitivity to hormone therapy (HR, 0.72; 95% CI, 0.55−0.94), whereas in patients without sensitivity, OS was not improved in the palbociclib group (HR, 1.14; 95% CI, 0.71−1.84; P = .12 for interaction).