Eligible subjects with advanced hepatocellular carcinoma and ovarian cancer will be divided into two treatment groups based on the volume of ascites. Group A consists of patients with mild ascites, who will receive NK521 via intravenous infusion. Group B includes patients with moderate to severe ascites, who will be treated with investigator-selected systemic regimens combined with intraperitoneal perfusion of NK521.
Systemic and local medications will be administered in accordance with the treatment regimens of respective groups, and the safety of the study drug will be monitored. Preliminary anti-tumor efficacy will be assessed using the RECIST 1.1 criteria at Week 6 after the first infusion of NK521. Catheter placement and ascites drainage will be performed 3 days prior to the first intraperitoneal perfusion of NK521. After the initial intraperitoneal perfusion treatment, the therapeutic effect on ascites will be evaluated per the WHO criteria for ascites assessment.