4529 Background: Cisplatin-based chemotherapy with or without high dose chemotherapy remains the standard approach in managing relapsed germ cell tumors (GCT). The feasibility of IPO was first described in 2006.Non cisplatin-based therapies offer the advantage of differing side effect profiles which may be useful to certain patients.Here we describe the outcome of an expanded cohort of these patients. Methods: The results of 72 consecutive patients were reviewed (18% had metastatic mediastinal GCTs). IPO was used either as 2nd line treatment (n=29) of which 20 had HDCT or 3rd line (n=43) of which 32 had HDCT. IPO consisted of oxaliplatin 100mg/m2, irinotecan 200mg/m2 and weekly pac litaxel 80mg/m2 ( IPO) every 3 weeks for 3-4 cycles with the intention of high dose carboplatin , thiotepa and topotecan as consolidation (HDCT). Results: The 2 year PFS and 3 year OS for the whole cohort was 28.4% (95%CI 17.3-40.5%) and 31.6% (95%CI: 20.1-43.8 %) respectively. The overall response was as follows; CR – 3%, m-ve PR 41%, m+ve PR 18%, SD 17%, PD 20%. In the second line setting, the 2 year PFS was 41.8% (95%CI: 21.7-60.8%) and 3y OS 45.8% (95%CI: 24.2-65.1%). The 2 year PFS according to the IGCCCG2 prognostic score was Intermediate = 34%, High risk =50% and very high risk = 30%. In the 3rd line setting the 2 year PFS was 20.9% (95%CI 9.5-35.4%) and 3 year OS was 23.8% (95%CI 11.7-38.2). For HDCT the 2 y PFS was good risk= 52%, Intermediate =29% and poor risk= 0%. There were 2 treatment related deaths from IPO, and 4 from HDCT. Grade 3 or 4 toxicities were as follows (>5%): neutropenia 35%, thrombocytopenia 18%, infection 15%, diarrhea 11%, lethargy 8%. Conclusions: IPO is a safe, non-nephrotoxic day care regimen which produces encouraging responses particularly in high risk cases. Where cisplatin is contra-indicated this is may be a useful alternative.