Table 1.
Previous clinical trials treating HR+/HER2+ MBC.
| Clinical trial | Phase | Cohort size | Treatment Regimen | Outcome (months) |
|---|---|---|---|---|
| ET ± single HER2-targeted therapy | ||||
| TAnDEM (24) | III | 207 | Trastuzumab + anastrozole vs anastrozole | PFS: 4.8 vs 2.4, HR = 0.63, p =0.0016 |
| eLEcTRA (25) | III | 57 | Trastuzumab + letrozole vs letrozole | PFS: 14.1 vs 3.3, HR = 0.67, p = 0.23 |
| EGF30008 (26) | III | 219 | Lapatinib + letrozole vs letrozole | PFS: 8.2 vs 3.0, HR =0.71, p =0.23 |
| ET + dual HER2-targeted therapy | ||||
| PERTAIN (27) | II | 258 | Pertuzumab + trastuzumab + AI vs trastuzumab + AI | PFS: 18.9 vs 15.8, HR =0.65, p =0.007 |
| ALTERNATIVE (28) | III | 355 | Lapatinib + trastuzumab + AI vs lapatinib + AI vs trastuzumab + AI | PFS: 11.0 vs 8.3 vs 5.7 |
| HER2-targeted therapy + ET or CT | ||||
| Sysucc-002 (29) | III | 392 | Trastuzumab + ET vs trastuzumab + CT | PFS: 19.2 vs 14.8 |
| Dual HER2-targeted therapy + ET± CT | ||||
| PERNETTA (30) | II | 210 | Trastuzumab + pertuzumab + ET vs trastuzumab + pertuzumab + ET + CT | 2-year OS: 75.0% vs 74.2% |
| CDK4/6 inhibitor | ||||
| monarcHER (31) | II | 237 | Abemaciclib+ fulvestrant + trastuzumab vs abemaciclib + trastuzumab vs standard-of-care chemotherapy + trastuzumab | PFS: 8.3 vs 5.7 vs 5.7 |
| PATRICIA (32) | II | 30 | Palbociclib + trastuzumab + letrozole vs palbociclib + trastuzumab | 6-month PFS: 42.8% vs 46.4% |
| ADC | ||||
| DESTINY-Breast03 (33) | III | 272 | Trastuzumab Deruxtecan vs Trastuzumab Emtansine | PFS: 22.4 vs 6.9 months, HR =0.32, 95%, p <0.001 |
AI, aromatase inhibitor, CDK, cyclin-dependent kinase, CT, chemotherapy, ET, endocrine therapy, HER2, human epidermal growth factor receptor 2, HR, hormone receptor; HR, hazard radio;l MBC, metastatic breast cancer; OS, overall survival; PFS, progression-free survival.