Phase I study of lapatinib plus vinorelbine in patients with locally advanced or metastatic breast cancer overexpressing HER2.

ABSTRACT: To determine the recommended doses of lapatinib (LPT) combined with vinorelbine (VNR) in women with human epidermal growth factor receptor 2-overexpressing advanced breast cancer pretreated with trastuzumab.In this phase I study, women were treated with oral daily LPT and i.v. VNR infused on days 1 and 8 every 3 weeks. Dose levels (DL) of LPT (mg)/VNR (mg m(-2)) ranged from 750/20 to 1250/30. The primary end point was feasibility based on maximal tolerated dose (MTD) and maximum administered dose (MAD). Pharmacokinetic interactions were investigated.Of 33 patients included, 29 were evaluable. Two DLT occurred at DL4 (1000/25) meeting the MAD criteria. Despite an additional intermediate DL3' (1250/22.5), MTD was reached at DL3 (1000/22.5). Grade 3-4 neutropenia was the most common toxicity (34% and 38% of patients, respectively). Other significant toxicities included grade 3-4 diarrhoea (3% each), and grade 3 asthenia (10%). Although not statistically significant, LPT (at 1000 or 1250 mg) decreased the VNR clearance by 30-40% compared with DL1.The MTD LPT 1000 mg/VNR 22.5 mg?m(-2) (DL3) is recommended for additional development. Pharmacokinetic interactions might increase the exposure to VNR and consequently alter the hematological tolerance.

SUBMITTER: Brain E 

PROVIDER: S-EPMC3322949 | biostudies-literature | 2012 Feb

REPOSITORIES: biostudies-literature