Trastuzumab and gemcitabine as salvage therapy in heavily pre-treated patients with metastatic breast cancer

Purpose In Her2-postive metastatic breast carcinoma, first-line trastuzumab-based therapy is well established; many centres continue antibody treatment beyond disease progression. In this trial, we evaluated the efficacy and safety of gemcitabine and trastuzumab after earlier exposure to anthracyclines, docetaxel and/or vinorelbine, and trastuzumab. Methods Twenty-nine consecutive patients were included as eligible. Patients received gemcitabine at a dose of 1,250 mg/m(2) on day one and eight, every 21 days. Trastuzumab was administered in three-week cycles. Clinical benefit rate (CBR; CR + PR + SD >= 6 months) was defined as primary endpoint. Results As of July 2007, all patients are evaluable for toxicity, and 26 for response. Earlier therapies consisted of trastuzumab (100%), anthracyclines (100%), vinorelbine (96.6%), docetaxel (72.4%), and capecitabine (72.4%). 19.2% of patients experienced PR, and SD >= 6 months was observed in a further 26.9%, resulting in a CBR of 46.2%. Time to progression was median 3 months, and overall survival 17 months. Neutropenia (20.7%), thrombocytopenia (13.8%), and nausea (3.4%) were the only treatment-related adverse events that occurred with grade 3 or 4 intensity. Four patients (13.8%) developed brain metastases while on therapy. Conclusions While CBR was low when compared to trastuzumab-based first-line therapy, it is higher than what would be expected from gemcitabine monotherapy in a similar setting. Together with the favourable toxicity profile, this regimen appears to be a safe and potentially effective salvage therapy option in a heavily pre-treated population.