Phase II Trial of Loubo® (Lobaplatin) and Pemetrexed for Patients with Metastatic Breast Cancer not Responding to Anthracycline or Taxanes

Purpose: This phase II study was undertaken to determine the efficacy and safety of Loubo® (Lobaplatin)in combination with pemetrexed in treating patients with metastatic breast cancer who failed to respond toanthracycline or taxanes. Patients and
Methods: Metastatic breast cancer cases who had previously received ananthracycline and a taxane in either adjuvant or metastatic settings, were enrolled. All patients were recruitedfrom Jiangsu Cancer Hospital and Research Institute, and were treated with Loubo® (Lobaplatin) 35 mg/m2(intravenous; on day 1) and pemetrexed 500 mg/m2 (intravenous; on day 1) every 21 days. Efficacy and sideeffects were evaluated after at least two cycles of chemotherapy.
Results: All eligible 19 patients completed atleast 2 cycles of chemotherapy with pemetrexed and lobaplatin, and were evaluable. Overall, 3 (15.8%) patientsachieved partial response, 11 (57.9%) stable disease, 5 (26.3%) progression of disease, with no complete remission.Response rate was 15.8%, disease control rate was 42.1%. The median survival time was 10.3 months. Neutrophilsuppression occurred in 36.8% of patients who had grade 2 toxicity, and 26.3% had grade 3, 26.4% had grade4. Thrombocytopenia was encountered as follows: 21.1% grade 2, 15.8% grade 3 and 5.5% grade 4. Incidencesof anemia were 10.5% in grade 2, 5.3% grade 3 and 0% grade 4. Only 5.3% of patients required packed redblood cell transfusion. Grade 3 digestive tract toxicity occurred in 5.5% of patients. Other toxicities includedelevated transaminase,oral mucositis and skin rashes.
Conclusions: The regimen of lobaplatin and pemetrexed ismodestly active in metastatic breast cancer patients who failed anthracycline or taxanes, and the toxicity profilesuggesting that the doses of chemotherapy should be further modified.