Tocilizumab for Painful Chronic Pancreatitis

Inclusion Criteria: * Signed informed consent. * Probable or definitive diagnosis of CP according to the M-ANNHEIM criteria. This entails a typical clinical history of CP, including recurrent pancreatitis or abdominal pain in combination with the following additional criteria: * A definitive diagnosis of CP is established by one or more of the following additional criteria: * i) Pancreatic calcification * ii) Moderate or marked ductal lesions (according to the Cambridge classification) * iii) Exocrine pancreatic insufficiency, defined as pancreatic steatorrhea markedly reduced by enzyme supplementation * iv) Histological verification of CP * A probable diagnosis of CP is established by one or more of the following additional criteria: * i) Mild ductal alterations (according to the Cambridge classification) * ii) Recurrent or persistent pseudocysts * iii) Pathological test of pancreatic exocrine function (such as faecal elastase-1 test, secretin test, secretin-pancreozymin test) * iv) Diabetes mellitus * Abdominal pain of presumed pancreatic origin (i.e., upper abdominal pain radiating to the back). * Evidence of ongoing pancreatic inflammatory activity, with an inflammatory pancreatic flare occurring one or more times within the past six months. An inflammatory pancreatic flare is defined as an exacerbation of pancreatic pain in combination with one or more of the following criteria: * i) Plasma amylase levels elevated 2-fold or more than the participant's usual amylase level. * ii) Elevated plasma levels of CRP 2-fold the upper normal level without suspicion of other sources such as infection. * iii) Signs of pancreatic inflammation on cross-sectional imaging. * ≥ 18 years of age * The participant must be able to read and understand the informed consent forms. * The participant is willing and able to comply with the scheduled visits, treatment plan, and other trial procedures. Exclusion Criteria: * End-stage CP indicated by severe pancreatic atrophy defined as segmented pancreas volume \<20 ml on the latest available cross-sectional imaging examination (Computed Tomography (CT) or MRI). * Pancreatic duct obstruction by a stricture and/or stone amendable to endoscopic or surgical treatment. Patients with previous pancreatic duct decompression procedures are allowed to participate. * Ongoing alcohol or substance abuse. The patient must document abstinence from alcohol and substance abuse for the preceding six months prior to study enrolment. Recreational al…