Oncolytic Virotherapy Plus PD-1 Inhibitor for Patients With Refractory Malignant Ascites

Inclusion Criteria: * Written informed consent obtained. * Age ≥ 18 years at time of study entry. * Pathologically diagnosed solid tumor malignancy. * Malignant peritoneal ascites confirmed by peritoneal brush cytology. * Failures from chemotherapy against malignant ascites. * Cooperative Oncology Group-Status (ECOG Status) 0 or 1 Exclusion Criteria: * Previous (\<4 weeks) or concurrent treatment with systemic or intraperitoneal chemotherapy or biological agents such as monoclonal antibodies. * History of cardiac disease, including clinically significant gastrointestinal bleeding within 4 weeks prior to start of study treatment * Thrombotic or embolic events such as cerebrovascular accident (including transient ischemic attacks), deep vein thrombosis or pulmonary embolism within the 6 months Prior to the first dose of study drug with the exception of thrombosis of a segmental portal vein. * Prior treatment with oncolytic virotherapy. * Radiotherapy administered less then 4 weeks prior to study treatment start. * Major surgery within 4 weeks of starting the study treatment OR subjects who have not recovered from effects of major surgery. * Patients with second primary cancer, except adequately treated basal skin cancer or carcinoma in-situ of the cervix. * Immunocompromised patients, e.g. patients who are known to be serologically positive for human immunodeficiency virus (HIV). * Participation in another clinical study with an investigational product during the last 30 day…