Background: The FOLFIRINOX regimen is highly active in APC, but its use is limited by toxicity. Irinotecan (IR) toxicity is correlated with UGT1A1 genotype status and chronomodulated delivery of fluoropyrimidines may reduce toxicity and increase efficacy. We have presented the dose escalation (DES) of OXIRI. In dose expansion (DXP), several pts required dose reduction after cycle 1 and we evaluated a lower starting dose. We now present data of the recommended Phase II dose (RP2D) and DES combined. Methods: Pts with APC and ECOG performance status ≤2, adequate organ function were enrolled. Previous OX or IR exposure was disallowed. During DES, APC pts homozygous for UGT1A1*6/*6 or UGT1A1*28/*28 were excluded. During DXP, only pts progressing on ≥ 1 line prior chemo was allowed and IR was dosed according to UGT1A1 genotype. At RP2D, pts received iv OX 37.5mg/m² and IR 50mg/m² on D1, 8 and po capecitabine 2650mg once at midnight on D1-14 every 21D until progression. Results: A total of 25 pts were enrolled, 17 in DES and 8 in DXP, 21 had metastatic and 4 had locally advanced APC. Male:Female 11:14, median (range) age and ECOG PS was 65yrs (50-77) and 0 (0-1) respectively. Pts with 0, 1 or 2 lines of prior chemo were 4 (16%) , 14 (56%) and 7(28%) respectively. Grade 3/4 AEs (≥5%) related to OXIRI were neutropenia (32%), anaemia (12%), diarrhoea (16%). No events of febrile neutropenia were reported. At data cut-off on 31 Aug 2017, 4 pts are on study. Median progression-free and overall survival was 22 and 35 wks respectively. Response rate (RR) was 5/25 (20%, overall); 5/20 (25%, evaluable pts) including 1 complete response and 1 unconfirmed partial response. Disease control rate for ≥ 12wks was 16/25 (64%) with 3 pts > 52wks. CA19-9 decrease of ≥ 20% was seen in 9/25 pts. Conclusions: OXIRI is an active regimen with RR of 20% despite 84% of pts having prior chemo, with disease control for ≥ 12wks in 64% of pts. Predominant toxicity was neutropenia. This study was supported by the National Medical Research Council Singapore. Clinical trial information: NCT02368860