Combination therapy with sitagliptin and lansoprazole in patients with recent-onset type 1 diabetes (REPAIR-T1D): 12-month results of a multicentre, randomised, placebo-controlled, phase 2 trial

Summary Background Type 1 diabetes results from autoimmune destruction of pancreatic β cells. Findings from preclinical studies suggest that dipeptidyl peptidase-4 inhibitors and proton-pump inhibitors might enhance β-cell survival and regeneration. We postulated that sitagliptin and lansoprazole would preserve β-cell function in patients with recent-onset type 1 diabetes. Methods We did a double-blind, placebo-controlled, phase 2 trial (REPAIR-T1D). Participants aged 11–36 years, diagnosed with type 1 diabetes within the past 6 months were recruited from Sanford Health Systems (Sioux Falls, SD, USA; Fargo, ND, USA), Children's Hospitals and Clinics of Minnesota (St Paul, MN, USA), and Rady Children's Hospital (San Diego, CA, USA). Participants were randomly assigned (2:1) to receive oral sitagliptin (100 mg for participants ≥18 years, 50 mg for those