Combination of tofogliflozin and pioglitazone for NAFLD: Extension to the ToPiND randomized controlled trial

The incidence of nonalcoholic fatty liver disease (NAFLD) has recently increased and is related to obesity and the associated surge in type 2 diabetes mellitus (T2DM) and metabolic syndromes. This trial follows up on our previous work and forms part of the ToPiND study. We aimed to combine tofogliflozin and pioglitazone treatment for hepatic steatosis in patients with NAFLD and T2DM. In this open-label, prospective, single-center, randomized clinical trial, patients with NAFLD with T2DM and a hepatic fat fraction of ≥10% were assessed based on magnetic resonance imaging proton density fat fraction. Eligible patients received either 20 mg tofogliflozin or 15-30 mg pioglitazone orally, once daily for 24 weeks, followed by combination therapy with both medicines for an additional 24 weeks. The effects on diabetes mellitus and hepatic steatosis were examined at baseline and after the completion of monotherapy and combination therapy. Thirty-two eligible patients received the combination therapy of tofogliflozin and pioglitazone. The combination therapy showed additional improvement in glycated hemoglobin compared with each monotherapy group and showed improvement in steatosis, hepatic stiffness, and alanine aminotransferase levels compared with the tofogliflozin monotherapy group. Pioglitazone monotherapy-mediated increase in body weight decreased following concomitant use of tofogliflozin. The combination therapy resulted in lower triglyceride, higher high-density lipoprotein cholesterol, higher adiponectin, and higher ketone body levels. Conclusion: In addition to the additive effects of tofogliflozin and pioglitazone in patients with T2DM and NAFLD, combination therapy was suggested to reduce weight gain and induce cardioprotective effect. Further studies with more patients are needed to investigate the combination therapy of various drugs.