5554 Background: Etoposide (E), cyclophosphamide (C) and tamoxifen (T) have been used as single agents in relapsed epithelial ovarian cancer (EOC) patients. We tested a low dose, continuous, daily, oral metronomic regimen that combined these 3 agents. Methods: This single centre prospective study included patients of relapsed EOC with exposure to at least 2 prior lines of chemotherapy (CT) and at least partial as the best response to most recent regimen. Study regimen comprised daily oral administration of E (50 mg/m2) and C (50 mg/m2) for 21 of a 28 day cycle plus T (20 mg/m2, twice per day) continuously. The primary endpoint was serological (CA-125) progression-free survival (PFS) as per Rustin Criteria and secondary endpoints were radiological (RECIST) PFS, overall survival (OS), duration of response (DOR), response rates and toxicity. The data cut-off date was 15 Jan 2013. Results: 26 patients with a median age of 48 years were accrued, of whom 21 had received 2 prior lines of CT and 5 had received 3 lines. 25 patients who were evaluable for analysis received a median of 6 (1-19) cycles of metronomic regimen. The median delivered relative dose intensities of E, C and T were 0.71, 0.71 and 0.97 respectively. 13 (52%) patients needed dose reduction after a median of 3 (1-9) cycles. Most common grade 3 or 4 toxicities included anemia, neutropenia, febrile neutropenia, nausea, vomiting and diarrhea in 44%, 36%, 12%, 16%, 16% and 12% patients respectively. 19 (76%) patients had serological CR or PR with a median time to response (TTR) and DOR of 1.8 (0.83-2.96) and 7.0 (95% CI, 5.8-8.2) months respectively. 11 (45.8%) of the 24 evaluable patients achieved radiological CR or PR with median TTR and DOR of 3.7 (1.8-7.2) and 5.5 (95% CI, 3.9-7.2) months respectively. 17, 18 and 7 patients have respectively experienced serological progression, radiological progression and death at the time of analysis. The median serological PFS, radiological PFS and OS are 7.9 (95% CI 7.2-8.6), 7.97 (95% CI, 5.95-9.98) and 22.3 (95% CI, 17.4-27.3) months, respectively. Conclusions: The oral metronomic combination of E, C and T has substantial and durable activity in relapsed EOC and is worthy of further evaluation in a larger randomized study.