GRN1005 Alone or in Combination With Trastuzumab in Breast Cancer Patients With Brain Metastases (GRABM-B)

Key Inclusion Criteria:

1. Age ≥ 18 years
2. Histologically or cytologically-documented breast cancer (HER2 status and ER/PgR status must be known)
3. Brain metastasis from breast cancer with or without prior WBRT
4. At least one radiologically-confirmed and measurable metastatic brain lesion (≥ 1.0 cm in the longest diameter) by Gd-MRI of the brain < 14 days prior to first dose (Metastatic brain lesions previously treated with SRS may not be target or non-target lesions)
5. Patients must be neurologically stable: On stable doses of corticosteroids and anticonvulsants (not EIAEDs, including phenytoin, phenobarbitol, carbamazepine, fosphenytoin, primidone, oxcarbazepine) for ≥ 5 days prior to obtaining the baseline Gd-MRI of the brain and ≥ 5 days prior to first dose
6. KPS ≥ 70%
7. Completed WBRT for intra-cranial lesions ≥ 28 days prior to first dose

Key Exclusion Criteria:

1. NCI CTCAE v4.0 Grade ≥ 2 neuropathy
2. CNS disease requiring immediate neurosurgical intervention (e.g., resection, shunt placement, etc.)
3. Known leptomeningeal disease