Table 2.
Regimen of first subsequent therapy after 1st-line and 2nd-line palbociclib treatment.
| Regimen | After 1st-line palbociclib (n = 224) |
After 2nd-line palbociclib (n = 235) |
|---|---|---|
| n (%) | n (%) | |
| ET alone | 39 (17.4) | 24 (10.2) |
| Fulvestrant | 17 (7.6) | 5 (2.1) |
| Tamoxifen | 6 (2.7) | 5 (2.1) |
| Exemestane | 4 (1.8) | 4 (1.7) |
| Letrozole | 4 (1.8) | 3 (1.3) |
| Toremifene | 3 (1.3) | 1 (0.4) |
| ET + CDK4/6i | 70 (31.2) | 70 (29.8) |
| Abemaciclib + fulvestrant | 36 (16.1) | 30 (12.8) |
| Abemaciclib + letrozole | 10 (4.5) | 9 (3.8) |
| Fulvestrant + palbociclib | 9 (4.0) | 8 (3.4) |
| Letrozole + palbociclib | 8 (3.6) | 8 (3.4) |
| ET + mTORi | 27 (12.1) | 30 (12.8) |
| Everolimus + exemestane | 25 (11.2) | 27 (11.5) |
| Chemotherapy alone | 50 (22.3) | 67 (28.5) |
| Eribulin | 13 (5.8) | 16 (6.8) |
| Tegafur + gimeracil + oteracil | 12 (5.4) | 18 (7.7) |
| Capecitabine | 11 (4.9) | 18 (7.7) |
| Paclitaxel | 3 (1.3) | 6 (2.6) |
| Cyclophosphamide + epirubicin | 3 (1.3) | 4 (1.7) |
| Chemotherapy + bevacizumab | 27 (12.1) | 30 (12.8) |
| Bevacizumab + paclitaxel | 27 (12.1) | 30 (12.8) |
| Chemotherapy + ET | 4 (1.8) | 9 (3.8) |
Abbreviations: ET, endocrine therapy; CDK4/6i, cyclin-dependent kinase 4/6 inhibitor; mTORi, mammalian target of rapamycin inhibitor.
Notes:Regimens used by ≥ 3 patients and patients treated with palbociclib in the first- or second-line settings (n = 459 of 1170 patients) are shown. CDK4/6i refers to palbociclib and abemaciclib.