Investigation of Canagliflozin Use in a Real-World Setting

Boston—Canagliflozin, the first sodium-glucose cotransporter-2 inhibitor, was FDA approved in March 2013 as an oral antidiabetic (OAD) treatment for type 2 diabetes. Dipeptidyl peptidase-4 (DPP-4) inhibitors are another relatively new class of OADs; the first agent was FDA approved in 2006. Little is known about the utilization of canagliflozin in a real-world setting compared with other OADs prescribed for glycemic control. In a new study, researchers investigated the demographic and clinical factors of patients initiating canagliflozin or DPP-4 therapy in a large commercially insured US population. The study’s outcomes were presented at the AMCP meeting during a poster session titled Demographic and Clinical Characteristics of Type 2 Diabetes Mellitus Patients Initiating Canagliflozin in a US Managed Care Population.

A retrospective claims study was conducted on adult patients identified from the HealthCare Integrated Research Database. Patients with ≥1 medical claim indicating a diagnosis of type 2
diabetes and ≥1 pharmacy claim for canagliflozin or any DDP-4 inhibitor between January 1, 2011, and September 30, 2013, were included.

The baseline period was defined as 12 months of pre-index continuous medical and pharmacy enrollment, while the follow-up period was defined as 3 months post-index enrollment. The researchers identified 1566 patients with claims for canagliflozin and 26,224 patients with claims for DPP-4 inhibitors. The mean age among the study participants was 54 years in the canagliflozin cohort and 44 years in the DPP-4 cohort. A significantly larger proportion of patients initiated canagliflozin therapy with a primary care physician compared with DPP-4 therapy (29.4% vs 9.9%, respectively; P<.001).

The findings showed that canagliflozin was often initiated as a second- or third-line therapy with a relatively high share of patients receiving concomitant antidiabetic injectables compared to DPP-4 inhibitors. At baseline, 70% of patients in both cohorts were receiving ≥1 other OAD, primarily metformin (64%), while a higher proportion of patients taking canagliflozin received injectables compared with DPP-4 patients, including insulin (25% vs 9%, respectively) and glucagon-like peptide-1 (GLP-1) receptor agonists (31% vs 4%, respectively).

Of the patients with hemoglobin A1c (HbA1c) results available at baseline, the canagliflozin patients had significantly lower prevalence of glycemic control (HbA1c <7%) compared with the DPP-4 patients (17% vs 27%, respectively). The canagliflozin cohort also had ≥1 pharmacy claim for major concomitant medications, including dyslipidemics and antihypertensives (74% and 73%, respectively) compared with the DPP-4
cohort (65% for both medication groups).

In a subsample of patients with at least 3 months of continuous medical and pharmacy enrollment after the index date, the researchers found that the average daily dose was titrated for 11% of canagliflozin patients compared with 2% of DPP-4 patients. In addition, concomitant medication use was higher among the canagliflozin cohort compared with the DPP-4 cohort for metformin (53% vs 37%, respectively), any insulin (18% vs 9%, respectively), and any GLP-1 receptor agonist (21% vs 3%, respectively).

The researchers acknowledged study limitations. Because patients were from 1 large US commercial health plan, the results may not be generalizable to patients enrolled in different plans or patients outside the United States. Also, follow-up results were only available over a 3-month period for a subsample of patients due to the recent FDA approval of canagliflozin.

“Future research is needed to examine changes in real-world clinical outcomes after canagliflozin initiation,” the investigators concluded.—Eileen Koutnik-Fotopoulos

This study was supported by Eli Lilly and Company.