Background: Acute kidney injury (AKI) is associated with incomplete recovery after the onset of the disease. However, there is no fundamental treatment for this disease. Previously, we identified vanin-1, which appears on the cell surface of proximal tubules early after oxidative stress and induces various inflammatory responses. In this study, we developed and evaluated vanin-1 inhibitors. We synthesized novel vanin-1 inhibitors (OMP compounds) by chemical modification of pantetheine analogues RR6 (IC50 = 0.54 μM), which was reported by Schalkwijk J et al. To evaluate the candidate compounds, vanin-1 activity in serum and renal tissues collected at 1 and 4 hours after subcutaneous administration of 10 mg/kg of RR6 or OMP7 to hamsters was compared with that in the normal group. Results/Conclusions: Serum vanin-1 activity was significantly decreased at 1 hour after subcutaneous administration of RR6, but there was no significant difference at 4 hours. On the other hand, vanin-1 activity was significantly suppressed at 1 and 4 hours after subcutaneous administration of the OMP7. Vanin-1 activity in renal tissue was also not inhibited at 1 hour after subcutaneous administration of RR6. In contrast, the OMP7 significantly inhibited vanin-1 activity at 1 hour after subcutaneous administration. These results suggest that compared to RR6, the OMP7 has a sustained inhibitory effect on vanin-1 activity in serum, and a certain inhibitory effect can be expected in renal tissues as well.