Sequential neoadjuvant chemotherapy for borderline resectable and locally advanced pancreatic adenocarcinoma.

TPS4209 Background: Patients with borderline resectable (BRPC) and locally advanced unresectable (LAPC) pancreatic cancer have a median OS of 8-20 months unless they undergo margin negative resection. Despite advances in systemic therapy, the prognosis is dismal. The locoregional and distant failure rates are high in post-surgery and therefore neoadjuvant chemotherapy emerged as standard-of-care practice to select the patients for surgery and improve overall clinical outcomes. An effective and tolerable neoadjuvant regimen can facilitate R0 resection by tumor down staging and mitigating the risk for positive margins. A recent SEQUENCE-2 study on sequential treatment with combination of Gemcitabine and nab-paclitaxel (GA) GA followed by modified FOLFOX (mFOLFOX) improved OS (13.2 months) and PFS (9.5 months) in patients with metastatic PDC, compared with the standard GA regimen, with comparable safety profile. Current guidelines suggest modified FOLFIRINOX (mFFX, infusional 5-fluorouracil, oxaliplatin, irinotecan) or GA as the first-line systemic chemotherapeutic regimen in neoadjuvant, adjuvant and palliative setting. These regimens are associated with modest pathological complete response rate. However, there is significant unmet need for management of BRPC and LAPC as the optimal treatment strategy remains undefined. As both of the aforementioned regimens are active and feasible in BRPC and LAPC, we conceptualize that by using both regimens alternating in sequence the rate of R0 resection and pathological response could be improved by overcoming possible resistance to a single backbone. Methods: The aim of this study is to demonstrate the efficacy and feasibility of sequential chemotherapy (GA followed by mFFX) in patients with BRPC (n=34) and LAPC (n=30). To achieve this, we are conducting a non-randomized prospective interventional clinical study with BRPC and LAPC patients treated with alternating cycles of GA and mFFX for 4 months and assessed for clinical outcomes, feasibility and toxicity. The primary objective of this study is to evaluate the efficacy of sequential GA followed by mFFX in improving R0 resection rate in patients with BRPC and LAPC. After four months of sequential neoadjuvant therapy, the patients will proceed to surgery, radiation, or extended course of chemotherapy, off study, as determined by multidisciplinary tumor board consensus or the treating physician. These results will have high translational potential for providing mechanistic insight into tumor response, optimizing current management strategies for pancreatic cancer that could be generalizable to other stages of this cancer. The key eligibility criteria include treatment naive histologically diagnosed BRPC or LAPC with measurable disease, ECOG 0,1, optimal organ function. Clinical trial information: NCT05776524 .