Studies on the Safety and Efficacy of Pyrotinib in the Treatment of HER2- Positive Advanced Solid Tumors Excluding Breast Cancer

Yuzhen Yin,1 Hui Yang,2 Zhuo Liu,3 Jie Tan,2 Chunrong Zhu,4 Minbin Chen,5 Rengui Zhou,6 Lei Wang,7 Jun Qian2,8 1Department of Tumor Center, The Affiliated Jiangsu Shengze Hospital of Nanjing Medical University, Suzhou, Jiangsu, People’s Republic of China; 2Department of Oncology, Suzhou Municipal Hospital, Suzhou, Jiangsu, People’s Republic of China; 3Department of Oncology, Zhangjiagang First People’s Hospital, Zhangjiagang, Jiangsu, People’s Republic of China; 4Department of Oncology, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu, People’s Republic of China; 5Department of Oncology, The First People’s Hospital of Kunshan, Kunshan, Jiangsu, People’s Republic of China; 6Department of Oncology, The 904th Hospital of the Joint Logistics Support Force of the Chinese People’s Liberation Army, Wuxi, Jiangsu, People’s Republic of China; 7Department of Breast Surgery, The First People’s Hospital of Changzhou, Changzhou, Jiangsu, People’s Republic of China; 8Department of Oncology, Jiangsu Province Hospital of Chinese Medicine, Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing, Jiangsu, People’s Republic of ChinaCorrespondence: Jun QianDepartment of Oncology, Jiangsu Province Hospital of Chinese Medicine, Affiliated Hospital of Nanjing University of Chinese Medicine, 155 Hanzhong Road, Qinhuai District, Nanjing, Jiangsu, People’s Republic of ChinaEmail junqian0415@126.comLei WangDepartment of Breast Surgery, The First People’s Hospital of Changzhou, No. 185, Juqian Street, Changzhou, Jiangsu, People’s Republic of ChinaEmail 592722409@qq.comBackground: Human epidermal growth factor receptor 2 (HER2) is a member of the ErbB family and is a key proto-oncogene in solid tumors. This pilot study investigated the safety and efficacy of pyrotinib in HER2-positive non-breast advanced solid tumors.Patients and Methods: Twenty-five patients with HER2-positive advanced solid tumors excluding breast cancer were enrolled to receive pyrotinib-based therapy. The primary end point was progression-free survival (PFS).Results: The median PFS and overall survival (OS) were 3.5 months (95% CI: 2.2– 5.0 months) and 9.6 months (95% CI: 4.4– 9.9 months), respectively. Ten patients with lung cancer and 9 patients with gastric cancer had a median PFS of 2.5 months (95% CI: 0.97– 6.53 months) and 2.9 months (95% CI: 1.50– 7.17 months), respectively. The median OS was 9.9 months (95% CI: 4.4– 9.9 months) in patients with lung cancer and 5.9 months (95% CI: 4.0– 9.6 months) in patients with gastric cancer. No statistical significance of a median OS was observed, nonetheless, patients receiving > 3 lines had a numerically lower median OS than those receiving ≤ 3 lines of treatment (9.9 vs 5.1 months, P = 0.706). All 23 patients were available for efficacy evaluation. The objective response rate (ORR) was 52.17% and disease control rate (DCR) was 91.3%. The ORR for lung cancer was 44.4% and for gastric cancer was 50%. In addition, the DCR for lung cancer was 77.8% and for stomach cancer was 100%. Moreover, patients receiving ≤ 3 lines of treatment had a numerically higher DCR than those receiving > 3 lines of treatment (94.1% vs 83.3%, P = 0.462). The most common treatment-related adverse events (TRAEs) were diarrhea (92%), but only 5 (20%) patients reported grade 3 diarrhea which could be well controlled.Conclusion: Pyrotinib-based therapy demonstrates promising efficacy for HER2-positive advanced solid tumors excluding breast cancer and toxicities could be well controlled. The study is a pilot study motivating larger studies to elucidate the safety and efficacy of pyrotinib in non-breast solid tumors.Keywords: pyrotinib, HER2-positive, solid tumor