Phase II study on the efficacy and safety of lapatinib administered beyond disease progression and combined with vinorelbine in HER-2/neu: Positive advanced breast cancer (CECOG LaVie Trial).

Background: This open-label, single-arm, multicenter phase II trial performed by the Central European Cooperative Oncology Group (CECOG) evaluated the efficacy and safety of the combination of vinorelbine and lapatinib in patients with HER-2/neu positive metastatic breast cancer as late-line therapeutic regimen. Methods: Patients with HER-2/neu-positive advanced breast had to be pretreated with lapatinib plus chemotherapy in first or second line for metastatic disease. Patients enrolled in this study were treated with vinorelbine (20 mg/m²i.v. on days 1 and 8), plus lapatinib (1250 mg orally once daily) until disease progression, intolerable toxicity, withdrawal or death. The primary endpoint was progression-free survival (PFS), secondary endpoints included overall survival (OS), objective response rate (ORR) and safety. The study was closed early due to slow accrual. Results: In total, 9 patients were enrolled. 6 patients had endocrine dependent disease. All patients were heavily pretreated and had received at least two lines of prior anti-cancer treatment for metastatic disease. Median PFS was 7.7 months (95%CI 0.56-14.91), median OS was 23.4 months (95%CI 16.61-30.13). Partial response was observed in one of 9 patients, 3 patients had stable disease of >6 months, whereas the remaining 5 patients had progressive disease. Individual patient data are shown in the table below. The majority of reported adverse events (AEs) were grade 1 and 2 in severity; most common AEs were diarrhea (17.9%), neutropenia (8.5%) and leukopenia (6.8%). AEs were consistent with the known lapatinib and vinorelbine safety profiles. Conclusions: The trial was terminated due to poor recruitment. Although limited by the small number of patients the combination therapy of vinorelbine and lapatinib resulted in a median PFS of 7.7 months and might represent a treatment option in heavily pretreated patients with HER-2/neu positive metastatic breast cancer.

Citation:
J Clin Oncol 33, 2015 (suppl; abstr e11603)

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