Safety and Efficacy of KN046 in Combination with KN026 in Patients with Advanced HER2-Positive Breast Cancer: A Phase
Jieqiong Liu1, Chuangui Song2, Yaping Yang1
1Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Breast Tumor Center, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China.
Purpose:
In this study, we report the results from a phase II trial assessing the safety and efficacy of KN046 in combination with KN026 in patients with HER2-positive metastatic breast cancer, who had progressed after prior anti-HER2 combination therapies.
Patients And Methods:
Female patients with metastatic HER2-positive breast cancer, who were previously treated with at least one line of HER2-targeted combination therapy, were enrolled from multiple academic hospitals in China to receive KN046 (i.v. 5 mg/kg every 3 weeks) plus KN026 (i.v. 30 mg/kg every 3 weeks) until progression, unacceptable toxicities, or patient withdrawal. Efficacy was evaluated every 6 weeks per RECIST 1.1. The primary endpoint was objective response rate.
Results:
A total of 36 patients with the median age of 53 years were enrolled. Of these 36 patients, 30 (83.3%) received ≥3 lines of HER2-targeted combination therapies in the metastatic setting. Thirty-three patients were evaluable for overall response and all 36 for safety. The objective response rate was 47.2% (95% confidence interval, 30.4-64.5), with two patients achieving complete response. The median progression-free survival was 5.6 months (95% confidence interval, 4.1-13.8). Of the 36 patients, 34 (94.4%) experienced treatment-related adverse events (TRAE) of any grade, and 10 of 36 (27.8%) patients had experienced ≥grade 3 TRAEs. The most common TRAEs were infusion-related reaction (36.1%), rash (16.7%), alanine aminotransferase increased (13.9%), diarrhea (13.9%), and pruritus (13.9%). No treatment-related deaths were observed.
Conclusions:
The combination of KN046 and KN026, as a chemo-free regimen, demonstrated favorable clinical efficacy with comparative toxicities in pretreated patients with advanced HER2-positive breast cancer.
