Study Design The study is a single-centre double-blinded sham-controlled randomized trial. All patients have the same baseline characterization. Patients and researchers will be blinded to allocation in trial. Before randomization patients will have an additional meal test performed addressing metabolic characterization of the incretine hormones at baseline. Patients will afterwards be allocated to either the group receiving G-POEM or to the control group where a sham procedure consisting of a gastroscopy with biopsy during general anaesthesia will be done. The randomization will be carried out per-operatively. A computer-generated bloc randomization with sizes of four will be applied. The study will consist of 5 study visits, with a follow-up of 90 days after procedure. Symptoms and adverse event will be monitored 7, 30, and 90 days after intervention. During the 90-day follow-up all primary and secondary outcome will be reassessed.~G-POEM procedure is carried out in general anaesthesia in the operating theatre at the Department of Surgery, Hvidovre Hospital. Procedures will be performed by experienced surgeons from the Gastro Unit at Hvidovre Hospital,who postoperatively will have no contact with the research team or study participants. Patients will receive the same care during hospitalization.~Patients allocated to sham procedure will have 4 mucosa biopsies from antrum. All biopsies will be handled with formalin and transported to Zealand University Hospital. Here they will be formalin fixed paraffin-embedded and kept in a biobank.
The goal of this randomized sham-controlled trial is to ivestigate efficacy and safety of G-POEM in treatment of diabetic gastroparesis and explore impact of G-POEM on glucose metabolism and incretine hormones.