A phase I study of lapatinib with whole brain radiotherapy in patients with Human Epidermal Growth Factor Receptor 2 (HER2)-positive breast cancer brain metastases.

Brain metastases are common in patients with advanced, Human Epidermal Growth Factor Receptor 2 (HER2)-positive breast cancer. We evaluated the maximum tolerated dose (MTD) and feasibility of lapatinib given concurrently with whole brain radiotherapy (WBRT). Eligible patients had (HER2)-positive breast cancer and ≥1 brain metastasis. Patients received lapatinib 750 mg twice on day one followed by 1000, 1250, or 1500 mg once daily. WBRT (37.5 Gy, 15 fractions) began 1-8 days after starting lapatinib. Lapatinib was continued through WBRT. Following WBRT, patients received trastuzumab 2 mg/kg weekly and lapatinib 1000 mg once daily. The regimen would be considered feasible if <3/27 pts treated at the MTD experienced a dose-limiting toxicity (DLT). Thirty-five patients were enrolled; 17 % had central nervous disease (CNS) only. During dose escalation, no patients receiving 1,000 or 1,250 mg and two of five patients receiving 1,500 mg experienced DLTs (grade 3 mucositis and rash). Overall, 7/27 patients at 1,250 mg (MTD) had DLTs: grade 3 rash (n = 2), diarrhea (n = 2), hypoxia (n = 1), and grade 4 pulmonary embolus (n = 2). Among 28 evaluable patients, the CNS objective response rate (ORR) was 79 % [95% confidence interval (CI) 59-92 %] by pre-specified volumetric criteria; 46 % remained progression-free (CNS or non-CNS) at 6 months. The study did not meet the pre-defined criteria for feasibility because of toxicity, although the relationship between study treatment and some DLTs was uncertain. Given the high ORR, concurrent lapatinib-WBRT could still be considered for future study with careful safety monitoring.

A phase II study of sagopilone (ZK 219477; ZK-EPO) in patients with breast cancer and brain metastases.

UNLABELLED: Treatments for women with recurrent brain metastases from breast cancer are limited. In this phase II study,we administered sagopilone to patients with breast cancer and brain metastases. We observed modest activity with a central nervous system objective response rate of 13.3%; however, median PFS was disappointing. Further studies should focus on other agents to treat this challenging clinical problem. BACKGROUND: Patients with progressive metastatic breast cancer to the central nervous system (CNS) have limited treatment options. PATIENTS AND METHODS: We conducted a phase II study of sagopilone, an epothilone B analogue that crosses the blood-brain barrier, in patients with breast cancer brain metastases. Women were treated with 16 mg/m(2) or 22 mg/m(2) intravenously every 21 days. The primary endpoint was CNS objective response rate (ORR). Secondary endpoints included toxicity, progression-free survival (PFS), and overall survival (OS). Using modified, high-resolution magnetic resonance angiography (MRA), we also evaluated changes in vessel tortuosity with treatment. RESULTS: Fifteen women were enrolled; all had progressive CNS disease despite whole-brain radiotherapy. Two patients achieved a partial response (ORR, 13.3%) and remained in the study for 6 cycles. Responses were not associated with normalization of tumor-associated vessels on correlative imaging studies. Median PFS and OS were 1.4 months and 5.3 months, respectively. The most common grade 3 toxicities were lymphopenia and fatigue. Enrollment was stopped prematurely because of limited observed activity and slow accrual. CONCLUSIONS: Sagopilone was associated with modest CNS activity in patients with breast cancer; however median PFS was disappointing. Further studies should examine other potentially active agents and/or combinations for this challenging clinical problem.