The study examined the effect of tolvaptan in patients with rapidly progressive autosomal dominant polycystic kidney disease (ADPKD) in China, where the drug was not yet approved at the time of the study despite international recommendations. The study included 89 patients, of whom 80% had a familial ADPKD, 40% had polycystic liver disease, and 65.6% had hypertension. The most frequently used daily doses of tolvaptan were 60 mg and 45 mg. After six months of treatment, the volume of the left kidney decreased by an average of 70.2 ml and after 12 months by 47.84 ml; the volume of the right kidney decreased by 42.69 ml after six months and by 8.57 ml after 12 months. Renal function as measured by eGFR remained stable with no major signs of liver or kidney damage. Tolvaptan was well tolerated and effectively slowed kidney volume growth in Chinese patients with rapidly progressive ADPKD.