Drug Utilization Patterns in Patients with Diabetes Initiating Sodium Glucose Co-Transporter-2 Inhibitors (SGLT2i) in Japan: A Multi-Database Study (2014–2017)

Abstract

Introduction: This study aimed to identify drug utilization patterns in patients initiating sodium glucose co-transporter-2 inhibitors (SGLT2i) in the first 3 years of their launch in Japan. Methods: This was a retrospective study using three administrative databases in Japan: a pharmacy claims database, a hospital-based database, and an insurance claims database. Prescription data were extracted from adult outpatients with diabetes who started SGLT2i between April 2014 and March 2017 to evaluate pre-index and concomitant medications. For glimepiride and insulin co-users, dose at SGLT2i add-on was also assessed. Results: Data from a total of 14,861 patients in the pharmacy dataset (P-dataset), 27,039 in the hospital dataset (H-dataset), and 12,408 in the insurance dataset (I-dataset) were analyzed. The majority of SGLT2i new users (ca. 70%) were taking one to three concomitant antidiabetic medications. Around half of SGLT2i initiators used dipeptidyl peptidase 4 inhibitors and/or biguanides before using SGLT2i or concomitantly with SGLT2i. The average daily glimepiride dose decreased from 2.1 mg/day during the pre-index period to 1.8 mg/day at SGLT2i add-on in the P-dataset and from 1.9 to 1.7 mg/day in the both H- and I-datasets, respectively, with a decreasing trend observed during the first 3 years of launch. The average daily insulin dose at SGLT2i add-on was higher during the first 15 months of launch and then decreased thereafter. Nearly 40% or more SGLT2i new users were taking at least five concomitant medications: cardiovascular agents were predominantly co-prescribed. Conclusion: SGLT2i were frequently used as second- or later-line treatment and as part of a dual, triple, or quadruple regimen, as well as co-prescribed with many other medications in the first 3 years of their launch. For SGLT2i users taking concomitant SU or insulin medications, the average daily doses of SU and insulin at SGLT2i add-on decreased slightly over the study period. Funding: Astellas Pharma Inc., Tokyo, Japan.