RESUMEN
The treatment paradigm for locally advanced pancreatic cancer (LAPC) is evolving rapidly. The development of neoadjuvant therapies composed of combination therapies and the evaluation of their impact on conversion to borderline resectable (BR) status, resection, and ultimately overall survival (OS) are presently being pursued. These efforts justify re-visiting study endpoints in order to better predict therapeutic effects on OS, by capturing not only the achievement of R0 resection at the end of induction therapy but also the long-term reductions in the rate of local and distal recurrence. The proposed herein event-free survival (EFS) endpoint, with its novel definition specific to LAPC, is formulated to achieve these objectives. It is an analog to disease-free survival (DFS) endpoint in the adjuvant setting applied to the neoadjuvant setting and may be a valuable surrogate endpoint for this patient population.
RESUMEN
PURPOSE: Pancreatic ductal adenocarcinomas exhibit a high degree of desmoplasia due to extensive extracellular matrix deposition. Encasement of mesenteric vessels by stroma in locally advanced pancreatic cancer (LAPC) prevents surgical resection. This study sought to determine if the addition of a monoclonal antibody to connective tissue growth factor, pamrevlumab, to neoadjuvant chemotherapy would be safe and lead to improved resectability in this surgically adverse patient population. METHODS: In this phase I/II trial, 37 patients with LAPC were randomised 2:1 to gemcitabine/nab-paclitaxel plus (Arm A, n=24) or minus (Arm B, n=13) pamrevlumab. Those who completed six cycles of treatment were assessed for surgical eligibility by protocol-defined criteria. Resection rates, progression-free and overall survival were evaluated. RESULTS: Eighteen (75%) patients in Arm A and seven (54%) in Arm B completed six cycles of therapy with similar toxicity patterns. In Arms A and B, carbohydrate antigen 19-9 response, as defined by ≥50% decline from baseline, occurred in 13 (65%) and 5 (42%), respectively. Sixteen (16%) per cent of patients were radiographically downstaged by National Comprehensive Cancer Network criteria (5 in Arm A (21%) and 1 (8%) in Arm B). Positron emission tomography normalised in 9 (38%) vs 3 (23%) of patients in Arm A vs Arm B, respectively, and correlated with surgical exploration. Eligibility for surgical exploration was 17 (71%) vs 2 (15%) (p=0.0019) and resection was achieved in 8 (33%) vs 1 (8%) of patients in Arm A vs Arm B (p=0.1193), respectively. Postoperative complication rates were not different between arms. CONCLUSIONS: Neoadjuvant chemotherapy with pamrevlumab holds promise for enhancing resection rates in patients with LAPC without added toxicity. This combination merits evaluation in a larger patient cohort.