A phase II clinical trial of albumin-bound paclitaxel, cisplatin, gemcitabine (NABPLAGEM) and paricalcitol as neoadjuvant therapy in pancreatic cancer

Background For patients with untreated pancreatic ductal adenocarcinoma (PDAC), chemotherapy before surgery (“neoadjuvant therapy”) has shown benefit in reducing recurrence and prolonging survival. Targeting the vitamin D receptor (VDR) with analogs such as paricalcitol may improve chemotherapy effectiveness. This study evaluated the efficacy and safety of neoadjuvant albumin-bound paclitaxel (nab-paclitaxel) plus cisplatin plus gemcitabine (NABPLAGEM) plus paricalcitol (NCT03138720). Methods Participants were ≥18 years, had stage I-III PDAC without prior chemotherapy or radiation, Karnofsky Performance Status ≥70, and elevated CA 19-9. Study treatment included nab-paclitaxel (125 mg/m2), cisplatin (25 mg/m2), gemcitabine (1000 mg/m2), and paricalcitol (25 mcg) on days 1 and 8 of a 21-day cycle for up to six months. The primary outcome was CA 19-9 normalization. Secondary outcomes included margin-negative resection (R0), pathologic complete response (pCR), radiologic response, safety, and survival. Microbiome was analyzed as an exploratory outcome. Results Thirty-two participants were enrolled with median age 69.4 years, 56.2% male, and 93.8% white. Patients had resectable (cohort A, n = 10) and borderline resectable/locally advanced (cohort B, n = 22) tumors. CA 19-9 normalization occurred in 14 patients (43.8%). Two patients (6.2%) achieved pCR, and 19 (59.4%) achieved R0. Complete or partial radiologic response occurred in 39.3% of patients. Adverse events included grade 3-4 anemia (43.8%) and thrombocytopenia (59.4%). Median (95% CI) overall survival was 43.2 (7.5–upper bound not achieved) and 18.4 (10.9–41.2) months for cohorts A and B, respectively. Conclusion Neoadjuvant NABPLAGEM plus paricalcitol demonstrated a high CA 19-9 normalization rate and was fairly well tolerated.