Nan Shen ¹ Lihong Zhang ² Jing Yang ³ Yongqiang Lin ⁴ Xinyu Liu ⁵ Xudong Cai ⁶ Juan Cao ⁷ Qiang Zhu ⁸ Xun Luo ⁹ Xin Wan ¹⁰ Henglan Wu ¹¹ Jianming Ye ¹² Chunyan Shan ¹³ Hua Xie ¹⁴ Yifan Wu ¹⁵ Yanping Cao ¹⁶ Jianmin Wang ¹⁷ Xiaoyong Yu ¹⁸ Huimin Wang ¹⁹ Jingdong He ²⁰ Shaojiang Tian ²¹ Fenglei Wu ²² Xinxin Jiang ²³ Lu Li ²⁴ Li ZUO ²⁵ Zhaohua wang ²⁶ Chang Xing ²⁷ Xun Yin ²⁸ Jianrong Zhao ²⁹ Cong Ma ³⁰ Gang Long ³¹ Qing Li ³² Yao Hu ³³ Yifan Shi ³⁴ Hong-Li Lin ^1*

• ¹ First Affiliated Hospital, Dalian Medical University, Dalian, China
• ² The First hospital of Hebei Medical University, Shijiazhuang, Hebei Province, China
• ³ Hefei No.1 People's Hospital, Hefei, Anhui Province, China
• ⁴ Wenzhou Hospital of Integrated Traditional Chinese and Western Medicine, Zhejiang Chinese Medical University, Wenzhou, Zhejiang Province, China
• ⁵ Nanyang City Center Hospital, Nanyang, China
• ⁶ Ningbo Traditional Chinese Medicine Hospital, Ningbo, Zhejiang Province, China
• ⁷ 7Taixing People’s Hospital, Taizhou, Jiangsu, China, jiangsu, China
• ⁸ Xinghua People's Hospital, xinghua, China
• ⁹ Hunan Provincial People's Hospital, Changsha, Hunan Province, China
• ¹⁰ The First Hospital of Nanjing, Nanjing, Jiangsu, China, Jiangsu, China
• ¹¹ The First Hospital of Jiaxing, Jiaxing, Zhejiang, China, Zhejiang, China
• ¹² The First People’s Hospital of Kunshan, Suzhou, Jiangsu, China, Jiangsu, China
• ¹³ Chu Hsien-I Memorial Hospital, Tianjin Medical University, Tianjin, China
• ¹⁴ Dalian Ruikaer Renal Disease Hospital, China, ..., China
• ¹⁵ 15Guangdong Provincial Hospital of Traditional Chinese Medicine, Guangzhou, Guangdong, China, Guangdong, China
• ¹⁶ Handan First Hospital, Handan, Heibei, China, Heibei, China
• ¹⁷ Linfen Central Hospital, Linfen, Shanxi, China, Shanxi, China
• ¹⁸ Shanxi Provincial Hospital of Chinese Medicine, Shanxi, China, Shanxi, China
• ¹⁹ Liaoning Health Industry Group Bensteel General Hospital, Benxi, Liaoning, China, Liaoning, China
• ²⁰ Nuclear Industry 416 Hospital, Chengdu, Sichuan, China, Sichuan, China
• ²¹ Shiyan People’s Hospital, Shiyan, Hubei, China, Hubei, China
• ²² Qidong People’s Hospital, The First Hospital of Tsinghua University, Beijing, China, Beijing, China
• ²³ Sandun District of Zhejiang Hospital, Zhejiang, China, Zhejiang, China
• ²⁴ First Affiliated Hospital of Xi'an Medical University, Xi'an, China
• ²⁵ Peking University People's Hospital, Beijing, Beijing Municipality, China
• ²⁶ Taian City Central Hospital, Tai'an, Shandong, China, Shandong, China
• ²⁷ Jiangsu Province Official Hospital, Nanjing, Jiangsu, China, Jiangsu, China
• ²⁸ Changshu No.2 People's Hospital, Suzhou, Jiangsu, China, Jiangsu, China
• ²⁹ The Affiliated Hospital of Inner Mongolia Medical University, Hohhot, Inner Mongolia Autonomous Region, China
• ³⁰ Anshan Central Hospital, Anshan, Liaoning, China, Liaoning, China
• ³¹ Tianjin People's Hospital, Tianjin, China
• ³² Tianjin TEDA Hospital, Tianjin, China
• ³³ Clinical Medical College & Affiliated Hospital of Chengdu University, Chengdu, Sichuan, China, Sichuan, China
• ³⁴ AstraZeneca Investment China Co, Medical Affairs, Shanghai, China, Shanghai, China

Introduction: Sodium zirconium cyclosilicate (SZC) is a nonabsorbed cation-exchanger approved in China for the treatment of hyperkalemia (HK; serum potassium [sK+] levels >5.0 mmol/L). This is the first real-world study aimed to assess the effectiveness, safety, and treatment patterns of SZC in Chinese patients with HK. Here we present the results of the first interim analysis. Methods: This multicenter, prospective, cohort study included patients aged ≥18 years with documented HK within 1-year before study enrollment day. These patients were followed up for 6 months from the enrollment day after initiating SZC treatment. The treatment was categorized into correction phase (FAS-P1) and maintenance phase (FAS-P2 new and ongoing users). Subgroup analysis was performed in patients on hemodialysis (FAS-H). The primary objective was evaluation of safety profile of SZC; secondary objectives included assessment of treatment patterns of SZC and its effectiveness. Results: Of 421 screened patients, 193, 354, and 162 patients were enrolled in the FAS-P1, FAS-P2, and FAS-H groups, respectively. sK+ levels were reduced significantly from 5.8 mmol/L to 5.0 mmol/L after the correction phase. For the maintenance phase, the mean sK+ levels were maintained at 5.2 mmol/L and 5.0 mmol/L in the FAS-P2 new and ongoing user, respectively, and 5.3 mmol/L in the FAS-H subgroup. A considerable proportion of patients showed normokalemia after 48h of SZC treatment (FAS-P1:51.3%) which was maintained up to 6 months in the maintenance phase (FAS-P2:44%). SZC was welltolerated. Conclusion: SZC was effective and safe for the treatment of HK in real-world clinical practice in China.