A PiLot ClinicaL TrIal of ParicAlcitol for ChroNiC PancrEatitis

Inclusion Criteria:

• Provision of signed and dated informed consent form

• Stated willingness to comply with all study procedures and availability for theduration of the study

• Male or female, aged 18-75 at time of enrollment

• Diagnosis of Chronic Pancreatitis episode is not attributable to gallstones (i.e.suspected or definite biliary etiology), medications, trauma or autoimmunepancreatitis.

• Ability to take oral medication and be willing to adhere to the dosing regimen

• Normal Calcium levels- 8.5 to 10.2 mg/dL

• Normal Phosphate levels- 2.8 to 4.5 mg/dL

• Normal Parathyroid hormone levels- 10 to 65 pg/mL

• For females of reproductive potential: use of highly effective contraception for atleast 1 month prior to screening and agreement to use such a method during studyparticipation and for an additional 1 week after the end of Investigational Productadministration

• For males of reproductive potential: use of condoms or other methods to ensureeffective contraception with partner

• No prior pancreatic surgery

• Pancreatic necrosis, if present, is <50% (to be verified by radiologist)

• No involvement in any interventional trials currently or within 6 months ofenrollment

Exclusion Criteria:

• Pregnancy or lactation

• History of autoimmune or traumatic pancreatitis, or sentinel attack of acutenecrotizing pancreatitis which results in suspected disconnected duct syndrome

• Primary pancreatic tumors - pancreatic ductal adenocarcinoma, suspected cysticneoplasm (>1 cms in size or main duct involvement), neuroendocrine tumors, and otheruncommon tumors.

• Pancreatic metastasis from other malignancies

• History of solid organ transplant, HIV/AIDS.

• Abnormal lab values: calcium, phosphate, or parathyroid hormone

• Known isolated pancreatic exocrine insufficiency (e.g. in the absence of anyeligible inclusion criteria)

• Participants must not have medical or psychiatric illnesses or ongoing substanceabuse that in the investigator's opinion would compromise their ability to toleratestudy interventions or participate in longitudinal follow up

• Patients with known abnormal creatinine (GFR < 30) or renal failure (applies topatients with chronic upper abdominal pain of suspected pancreatic origin andsuspected CP.

• Known Pregnancy. All participants of childbearing potential, except ifpost-menopausal [i.e. no menses for ≥2 years] or had a hysterectomy, bilateral tuballigation/clip (surgical sterilization) or surgical removal of both the ovaries),must have a negative urine or serum B-HCG pregnancy test documented within 2 daysprior to any endoscopic or radiologic procedures done for research purposes. Anystandard of care tests will follow institutional policies regarding pregnancy test

• Currently incarcerated

• Inability to tolerate MRI