A Study of Maintenance Treatment With Fluzoparib in gBRCA/PALB2 Mutated Pancreatic Cancer Whose Disease Has Not Progressed on First Line Platinum-Based Chemotherapy

Key Inclusion Criteria: * Aged ≥ 18 years. * Eastern Cooperative Oncology Group (ECOG) Performance Status (PS) of 0 or 1 * Expected survival ≥ 3 months. * Histologically or cytologically confirmed metastatic pancreas adenocarcinoma. * Patients who have received a minimum of 16 weeks of continuous platinum treatment for metastatic disease and have no evidence of progression based on investigator's opinion. * Patients with measurable disease and/or non-measurable or no evidence of disease assessed at baseline by CT or MRI. * Documented mutation in germline BRCA1/2 or PALB2 that is predicted to be deleterious or suspected deleterious. * Adequate organ performance based on laboratory blood tests. * Women of childbearing potential and men must agree to use adequate contraception prior to study entry and for the duration of study participation. * Ability to understand and the willingness to sign a written informed consent document. Major Exclusion Criteria: * Previous treatment with a poly ADP-ribose polymerase (PARP) inhibitor. * Patients who have had radiotherapy within 2 weeks or participated in another clinical trial with any investigational agents within 2 weeks prior to study screening. * Previous treatment using CYP3A4 inducers within 3 weeks or inhibitors within 2 weeks. * Significant cardiovascular disease such as New York Heart Associate Class III/IV, cardiac failure, myocardial infarction, unstable arrhythmia, or evidence of ischemia on ECG within 6 months prior to enrolment. * Patients unable to swallow orally administered medication and patients with gastrointestinal disorders likely to interfere with absorption of the study medication. * Patients with myelodysplastic syndrome/acute myeloid leukaemia. * Known active hepatitis B or C infection. * History of immunodeficiency (including HIV infection) or organ transplantation. * Other serious accompanying illnesses, which, in the researcher's opinion, could seriously adversely affect the safety of the treatment.