HX008, an anti-PD1 antibody, plus irinotecan as second-line treatment for advanced gastric or gastroesophageal junction cancer: a multicenter, single-arm phase II trial ======================================================================================================================================================================== * Yan Song * Ning Li * Qun Li * Xinjun Liang * Shu Zhang * Qingxia Fan * Xianli Yin * Zhixiang Zhuang * Yunpeng Liu * Jingdong Zhang * Xiaoge Kou * Haijun Zhong * Xiaofei Wang * Yiwei Dou * Jing Huang