Abstract OT1-1-11: TBCRC 022: Phase II Trial of Neratinib for Patients with Human Epidermal Growth Factor Receptor 2 (HER2)-Positive Breast cancer and Brain Metastases

Abstract

Abstract Background: 1/3 of women with metastatic HER2+ breast cancer will develop central nervous system (CNS) metastases yet evidence-based treatments for women with progressive CNS disease are limited. Neratinib is an irreversible inhibitor of erbB1, HER2, and erbB4 which has promising activity in HER2+ breast cancer. Preclinical evidence suggests it may cross the blood brain barrier. Trial Design: This is a multicenter, phase II, open-label study of neratinib for patients with HER2+ breast cancer and brain metastases. Neratinib is administered at 240 mg orally daily during a 28 day cycle. Two cohorts will be enrolled: Cohort 1 will enroll 40 patients with progressive CNS disease; cohort 2 will enroll ≤5 patients who are candidates for surgical excision of intracranial disease. Surgical candidates receive neratinib 7–21 days preoperatively and resume postoperatively. All patients are re-staged every 2 cycles. Those who develop non-CNS progression have an option to extend therapy with trastuzumab+neratinib. Circulating tumor cells (CTC) are collected at baseline and progression; neurocognitive testing, HADS and EORTC QLQ30/BN20 measures are administered at baseline, cycle 2, cycle 3, and progression (cohort 1). Intracranial tumor, cerebrospinal fluid (CSF), and plasma are collected at surgery (cohort 2). Specific Aims: The primary endpoint is CNS objective response rate (ORR) by composite criteria. Additional endpoints include: non-CNS ORR, progression-free survival, overall survival (OS), site of 1st progression, and toxicity. Correlative and exploratory endpoints include association of CTC count and OS and longitudinal neurocognitive function and quality of life. In an exploratory analysis (cohort 2), we will quantify neratinib concentrations in CSF, intracranial tissue, and plasma and examine associations with response. Eligibility: Patients must have confirmed HER2+ metastatic disease with ≥1 parenchymal brain lesion measuring ≥10 mm that is new or progressed after completing ≥1 line of standard CNS-directed treatment (cohort 1) or CNS disease that is amenable for surgery, including those without prior CNS treatments (cohort 2). Additional eligibility criteria (cohorts 1,2) include: adequate performance status and end organ/marrow function, and ejection fraction ≥50%. Any number of prior lines of therapy is allowed, including prior lapatinib. Statistical Methods: Cohort 1 has a 2-stage design with up to 40 patients. CNS ORR is defined as ≥50% reduction in sum volume of CNS target lesions, without evidence of new lesions, progression of non-target CNS lesions, non-CNS disease progression, worsening neurological symptoms, or increase in corticosteroids. CNS lesion measurements are performed centrally by the Harvard Tumor Imaging Metrics Core. If 1/18 patients have a CNS response in the 1st stage, another 22 patients will enroll. With this design, if ≥5 of 40 patients achieve a CNS response, the drug will be deemed worthy of future study. This 2-stage design has 92% power to distinguish between a true CNS ORR of 20% and a null of 6% (one-sided type I error rate=9%). Accrual: Accrual has begun. Target=45 (cohort 1=40, cohort 2=5) Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr OT1-1-11.