Safety and effectiveness of tofogliflozin in Japanese people with type 2 diabetes: A multicenter prospective observational study in routine clinical practice

Aims/Introduction

Sodium–glucose cotransporter 2 (SGLT2) inhibitors effectively and safely reduce fasting and postprandial hyperglycemia while promoting weight loss. However, their unique mechanism of action contributes to concerns regarding their safety. We therefore carried out a large-scale, non-commercial, investigator-initiated study on the safety and effectiveness of the SGLT2 inhibitor tofogliflozin.

Materials and Methods

This multicenter, open-label, uncontrolled, prospective observational study was carried out at hospitals and clinics across Japan in participants aged ≥20 years who were SGLT2 inhibitor-naïve and had an established diagnosis of type 2 diabetes. The primary endpoint was adverse drug reactions (ADRs) of special interest. Secondary endpoints included all other ADRs and adverse events, glycated hemoglobin (HbA1c), and weight loss.

Results

The study, carried out from June 2014 through February 2020, enrolled 11,480 participants from 1,103 medical institutions; 6,967 participants completed the 104-week follow up. The most common ADRs of special interest were urinary and genital tract infections (1.53%), followed by volume depletion (1.25%). Hypoglycemia occurred in 27 participants (0.24%), adverse events in 1,054 (9.18%) and ADRs in 645 (5.62%). HbA1c decreased by 0.85% (95% confidence interval 0.82%–0.88%) and bodyweight decreased by 3.05 kg (95% confidence interval 2.94–3.17 kg). The HbA1c target was achieved by 51.70% of participants for target HbA1c <7.0%, 85.3% for <8.0% and 5.4% for <6.0% at week 104.

Conclusions

Tofogliflozin was associated with only mild or moderate ADRs characteristic of SGLT2 inhibitors, with no unpredictable, new, serious, or high-incidence adverse events or ADRs. This independent study confirmed the safety and effectiveness of tofogliflozin in adult type 2 diabetes patients.