Objective: To evaluate the efficacy and safety of 1-year adjuvant trastuzumab (herceptin) versus 1-year non-trastuzumab observation in Chinese patients with HER2-positive early breast cancer during a median follow-up of 1 year.
Methods: The HERA trial was an international, multicenter, randomized, open-label, phase III trial comparing treatment with trastuzumab for 1 and 2 years with observation after standard adjuvant chemotherapy, radiotherapy or both in patients with HER2-positive node-positive or high-risk node-negative early breast cancer. The primary endpoint was disease-free survival. Secondary end points included recurrence-free survival, distant disease-free survival, overall survival and cardiac safety. The first planned interim analysis comparing the efficacy and safety of treatment with trastuzumab for 1 year versus observation were completed in April 2005. Only the outcomes of recruited Chinese patients were reported.
Results: A total of 122 Chinese patients from 8 participating centers were included for planned interim analysis. And they were divided into trastuzumab (n = 68) and observation (n = 54) groups. Three and eight disease-free survival events were observed in the trastuzumab and observation groups respectively. Two-year disease-free survival rates were 92.9% and 81.4% respectively (P = 0.0489); 2-year recurrence-free survival and distant disease-free survivals were 98.1% vs 81.4% (P = 0.0064) and 98.1% vs 83.3% (P = 0.0117) respectively. Trastuzumab was generally well-tolerated with a decent safety profile. Severe cardiotoxicity was not observed.
Conclusion: One-year treatment with adjuvant trastuzumab improves disease-free survival, recurrence-free survival and distant disease-free survival in Chinese patients with HER2-positive early breast cancer.