BreakthroughT1D said Tregopil had a successful phase 1 trial in T1D in their monthly newsletter. Since we were talking about another paper on an oral insulin I looked it up. This one is real. The pharmacodynamics mean it is currently being looked at as a adjunct to fast acting insulins not a replacement.
Since that paper has a paywall here is a previous phase 1 study on the same drug in PwT2D that is free. Pharmacokinetics and Pharmacodynamics of Insulin Tregopil in Relation to Premeal Dosing Time, Between Meal Interval, and Meal Composition in Patients With Type 2 Diabetes Mellitus - PMC