Paclitaxel protein bound (A) plus gemcitabine (G) plus cisplatin (C) and hydroxychloroquine (HCQ) neoadjuvant therapy for localized pancreatic ductal adenocarcinoma (PDAC).

Abstract

667 Background: Neoadjuvant therapy has become the consensus treatment for individuals with locally advanced (LA) and borderline resectable (BR) PDAC. Neoadjuvant therapy for resectable (R) PDAC has been in greater use due to concerns over micro metastases at diagnosis. Typical therapies involve the use of multiagent systemic chemotherapy with or without radiation therapy. In retrospective studies, Cancer Antigen 19-9 (CA 19-9) normalization in borderline resectable (BR) and locally advanced (LA) PDAC has been associated with greater OS. The addition of cisplatin (C) to gemcitabine (G) and paclitaxel protein bound (A), has shown promising clinical data in a previously reported study in advanced PDAC [JAMA Oncol. 2020;6(1):125-132]. HCQ has been shown to target autophagy in PDAC and has demonstrated higher response in combination with GA. We conducted a prospective, phase 2 clinical trial of patients with R, BR, and LA PDAC utilizing a regimen combining A + G + C + HCQ with the primary endpoint of CA 19-9 normalization (NCT04669197). Methods: Eligibility criteria include patients with histologically confirmed R, BR, or LA PDAC, elevated CA 19-9, and a KPS ≥ 70% with normal end organ function. Doses are A 125 mg/m2, G 1000 mg/m2, C 25 mg/ m2 on days 1, 8 of a 21-day cycle (IV) along with HCQ 600 mg po bid. Primary objective is to evaluate CA 19-9 normalization with the neoadjuvant chemotherapy. Secondary objectives are to assess R0 rate, pathologic complete response (pCR), safety and tolerability, radiologic response rate (by RECIST 1.1), and 2 year overall survival (OS) from date of study entry. Exploratory objectives include evaluating imaging biomarkers and vascular involvement by tumor in relation to therapy. Results: To date all planned 12 patients have been enrolled, 11 evaluable. 8 male, 4 female; age range 50 to 76 yo. Patient classifications is 3 R; 4 BR; 5 LAPC. Most common drug related grade (gr) 3-4 adverse events (AEs) are: thrombocytopenia gr 3 27%, gr 4 27%, anemia gr 3 36%, and neuropath gr 3 36%. CA 19-9 normalization occurred in 36% (4/11) who have completed at least 1 cycle of treatment. To date, 3 individuals went to surgery, with 3 achieving R0. Overall response rate in measurable patients is 45% (1CR, 4 PR). Median OS and 2-year survival data are not yet matured. Conclusions: In patients with non-metastatic PDAC, the use of A+G+C+HCQ resulted in a CA 19-9 normalization rate in 36% of individuals. Most patients did not go to surgery. The OS data is maturing. Supported by grants from the HonorHealth Foundation and Marley Foundation. Clinical trial information: NCT04669197 .