Study to Assess the Safety and Tolerability of a PARP Inhibitor in Combination With Topotecan

Inclusion Criteria: * Histological or cytological diagnosis of advanced solid tumour for which no suitable effective therapy exists; * Evaluable disease * Adequate bone marrow, hepatic and renal function Exclusion Criteria: * Any chemotherapy, radiotherapy ( except palliative), endocrine or immunotherapy within 4 weeks prior to entry; major surgery with 4 weeks of entering the study * Heavily pre treated patient \> 2 previous chemotherapy regimens for metastatic disease * Co-existing active infection