Table 2:
Combination strategies of therapeutic agents in trials for breast cancer brain metastases as found in ClinicalTrials.gov as of October 9, 2019 (n = 65).
| Drug Description | NA | Phase I | Phase I/II | Phase II | Phase III | Total | |
|---|---|---|---|---|---|---|---|
| Number of Trials | 1 | 9 (14%) | 8 (12%) | 39 (60%) | 8 (12%) | 65 (100%) | |
| Combination Strategy | |||||||
| Chemotherapy Agents (≥2) | - | 4 | 5 | 26 | 5 | 40 (62%) | |
| Chemotherapy + WBRT | 1 | 4 | - | 9 | 1 | 15 (23%) | |
| Chemotherapy + SRS | - | 1 | 2 | 2 | - | 5 (8%) | |
| Chemotherapy + WBRT or SRS | - | - | 1 | - | - | 1 (2%) | |
| Chemotherapy + Surgery | - | - | - | - | 1 | 1 (2%) | |
| WBRT + SRS | - | - | - | 1 | 1 | 2 (3%) | |
| Chemo + Diet | - | - | - | 1 | - | 1 (2%) | |
| Therapeutic Agents | |||||||
| Abemaciclib | CDK inhibitor | - | 1 | - | - | - | 1 (2%) |
| Afatinib | Tyrosine kinase inhibitor | - | - | - | 1 | - | 1 (2%) |
| Atezolizumab | PD-L1 inhibitor | - | - | - | 2 | 2 | 4 (6%) |
| Bevacizumab | VEGF-A inhibitor | - | - | - | 5 | - | 5 (8%) |
| BKM120 | PI3K inhibitor | - | - | 1 | 1 | - | 2 (3%) |
| Cabazitaxel | Taxane, microtubule inhibitor | - | - | - | 1 | - | 1 (2%) |
| Cabozantinib | Tyrosine kinase inhibitor | - | - | - | 1 | - | 1 (2%) |
| Caelyx | Topoisomerase inhibitor | - | - | - | 1 | - | 1 (2%) |
| Capecitabine | Thymidylate synthase inhibitor | - | 1 | - | 8 | 1 | 10 (15%) |
| Carboplatin | Alkylating agent, Cross-links DNA | - | - | 1 | 1 | - | 2 (3%) |
| Cisplatin | Alkylating agent, Cross-links DNA | - | - | - | 4 | - | 4 (6%) |
| Cytarabine | DNA polymerase inhibitor | - | - | - | 1 | - | 1 (2%) |
| Docetaxel | Taxane, microtubule inhibitor | - | - | - | 2 | - | 2 (3%) |
| Durvalumab | PD-1 inhibitor | 1 | - | - | - | - | 1 (2%) |
| Efaproxiral | Propanoic acid | - | - | - | - | 1 | 1 (2%) |
| Etoposide | Topoisomerase inhibitor | - | - | - | 2 | - | 2 (3%) |
| Everolimus | mTOR inhibitor | - | - | 1 | 2 | - | 3 (5%) |
| Galinpepimut-S | WT1 peptide vaccine | - | - | 1 | - | 1 (2%) | |
| GDC-0084 | PI3K inhibitor | - | - | - | 1 | - | 1 (2%) |
| Gemcitabine | Nucleoside analog | - | - | - | 1 | - | 1 (2%) |
| GRN1005 | Taxane, microtubule inhibitor | - | - | - | 1 | - | 1 (2%) |
| GW572016 | Tyrosine kinase inhibitor | - | - | - | - | 1 | 1 (2%) |
| Indinavir+Ritonavir | Protease inhibitors | - | - | - | 1 | - | 1 (2%) |
| Iniparib | PARP inhibitor | - | - | - | 1 | - | 1 (2%) |
| Irinotecan | Topoisomerase inhibitor | - | - | - | 4 | - | 4 (6%) |
| Lapatinib | Tyrosine kinase inhibitor | - | 3 | 1 | 7 | 2 | 13 (20%) |
| Letrozole | Aromatase inhibitor | - | - | - | - | 1 | 1 (2%) |
| Methotrexate | Dihydrofolate reductase inhibitor | - | - | 1 | 1 | - | 2 (3%) |
| Nivolumab | PD-1 inhibitor | - | 1 | - | - | - | 1 (2%) |
| ONC201 | Dopamine receptor antagonist | - | - | - | 1 | - | 1 (2%) |
| Paclitaxel | Taxane, microtubule inhibitor | - | - | - | 1 | 1 | 2 (3%) |
| Peginterferon Alfa-2a | Alpha interferon | - | - | - | 1 | - | 1 (2%) |
| Pembrolizumab | PD-1 inhibitor | - | - | 2 | - | - | 2 (3%) |
| Pertuzumab | HER-dimerization inhibitor | - | - | - | 2 | 1 | 3 (5%) |
| Pyrotinib | Tyrosine kinase inhibitor | - | - | - | 2 | - | 2 (3%) |
| RO4929097 | Gamma secretase inhibitor | - | - | 1 | - | - | 1 (2%) |
| Sorafenib | RAF kinase inhibitor | - | 1 | - | - | - | 1 (2%) |
| Sunitinib | Tyrosine kinase inhibitor | - | - | - | 1 | - | 1 (2%) |
| TDM-1 | HER-dimerization inhibitor/microtubule inhibitor | - | 1 | - | - | - | 1 (2%) |
| Temozolomide | Alkylating agent | - | 1 | 2 | 3 | - | 6 (9%) |
| Tesevatinib | Tyrosine kinase inhibitor | - | - | 1 | - | - | 1 (2%) |
| Topotecan | Topoisomerase inhibitor | - | - | - | 1 | - | 1 (2%) |
| Trastuzumab | HER2 receptor inhibitor | - | 2 | 4 | 10 | 3 | 19 (29%) |
| Tremelimumab | CTLA-4 inhibitor | 1 | - | - | - | - | 1 (2%) |
| Tucatinib | HER2 receptor inhibitor | - | 2 | - | 1 | 1 | 4 (6%) |
| Veliparib | PARP inhibitor | - | - | - | 1 | - | 1 (2%) |
| Vinorelbine | Vinca alkaloid, tubulin inhibitor | - | - | - | 3 | 1 | 4 (6%) |
| Vorinostat | Histone deacetylase inhibitor | - | 1 | - | - | - | 1 (2%) |
WBRT: whole brain radiation therapy, SRS: stereotactic radiosurgery.