It used thiazolidide as the P1 - substitute .
Was the first DPP - 4 inhibitor that showed effects in both animals and humans but it was not developed to a market drug due to side effects .
It used thiazolidide as the P1 - substitute and was the first DPP - 4 inhibitor that showed effects in both animals and humans but it was not developed to a market drug due to side effects .