Trial of THEO-260 (Administered Via Intraperitoneal Route) in Ovarian Cancer Patients

* Inclusion Criteria: * Confirmed histological diagnosis of advanced high grade serous or endometrioid cancer of the fallopian tube, primary peritoneum or ovary either on archival biopsy or fresh tumour biopsy. * Platinum-resistant or refractory disease: platinum-resistance is defined as radiological progression within 6 months of last cycle of platinum treatment; platinum refractory disease is defined as radiological progression during the 3 months following the first dose with platinum treatment. * Life expectancy of \> 6 months. * ECOG performance status of 0 or 1. * Measurable disease as per RECIST V1.1. * No clinical history of bowel obstruction in past 3 months or no clinical signs or symptoms of bowel obstruction. Exclusion Criteria: * Prior anti-cancer treatment or Investigational Product within 28 days or 5 half-lives, prior to first dose of THEO-260. * Prior treatment with a group B adenovirus. * Radiation therapy within 4 weeks of first dose of THEO-260 * Clinical evidence of cerebral metastases or Central Nervous System (CNS) involvement including leptomeningeal disease. Patients with previous cerebral metastases must have no evidence of progression or haemorrhage after treatment. * Uncontrolled pleural effusion or pericardial effusion requiring recurrent drainage procedures (as defined as once monthly or more frequently). * Prior pneumonitis or history of interstitial lung disease. * Confirmed QTcF ≥470 ms on screening 12-lead ECG or history of Torsades de Poin…