Background: Patients with metastatic pancreatic cancer who have progressed on two prior lines of therapy have a poor prognosis with an overall survival in the range of 2-2.5 months. (Manax, et al. J Clin Oncol 37, 2019 suppl 4; abstr 226). There is currently no standard of care for these patients that has demonstrated improved outcomes. SM-88 (D,L-alpha-metyrosine; racemetyrosine [USAN]) is a proprietary dysfunctional tyrosine derivative and is the backbone of SM-88 used with MPS (Methoxsalen 10mg, Phenytoin 50mg and Sirolimus 0.5mg; all administered daily). SM-88 monotherapy was relatively well tolerated, with improvement in survival in select patients with heavily pretreated PDAC who achieved stable disease on therapy (HR 0.08, p = 0.02). Circulating tumor cells (CTC’s) were prognostic and decreased on therapy with SM-88 potentially identifying a subgroup of PDAC that may be most likely to benefit from therapy (Noel et al. Annal Oncol V30, Suppl 4, 2019). Preliminary radiomic analysis of the largest metastases at baseline suggested the same benefits including a correlation with baseline CTCs, changes in CTCs on therapy and OS (Ocean et al, Annal Oncol, V30, Suppl 5, 2019). Here, we describe a randomized, open-label, phase 2/3 trial evaluating the efficacy of SM-88 + MPS vs physician’s choice treatment as third line therapy for patients with metastatic PDAC. Methods: This is a multi-center Phase 3 study of patients ≥18 years with metastatic PDAC that progressed after 2 lines of chemotherapy (gemcitabine [gem] and 5-fluorouracil [5-FU] based) with an ECOG <2. Randomization will be 1:1 with 250 patients being stratified by site, ECOG, and choice of chemotherapy. SM-88 will be administered at a dose of 460mg twice daily (920 mg/day). Primary end point is Overall Survival (OS). Secondary end points include progression free survival, response rate, duration of response, pharmacokinetics, safety and CTCs. Clinical trial information: NCT03512756