Chicago, IL—Microvascular and macrovascular complications in type 2 diabetes were shown to be reduced with canagliflozin (Invokana) 100 mg and 300 mg compared with lifestyle measures alone, according to Cheryl A. Neslusan, PhD, Global Strategic Marketing and Market Access, Janssen Global Services, Raritan, NJ, and colleagues. They presented the results of their long-term economic model at the 2013 American Diabetes Association annual meeting.
Dr Neslusan and colleagues noted that this is the first economic model to analyze the cost benefits for patients with type 2 diabetes with the use of canagliflozin that reflect the 2012 treatment patterns of microvascular and macrovascular events in this setting, showing “sizable gains in life-years and QALYs [quality-adjusted life-years] and substantial cost offsets.”
The data came from the phase 3 DIA3005 study of canagliflozin, the first-in-class sodium glucose cotransporter (SGLT)-2 inhibitor that had recently received US Food and Drug Administration approval for the treatment of patients with type 2 diabetes in addition to diet and exercise.
In the DIA3005 study, the 100-mg dose of the SGLT-2 inhibitor reduced hemoglobin (Hb) A1c by 0.91% and by 1.16% with the 300-mg dose compared with placebo. The 584 patients (aged 55 years) in that study had a baseline HbA1c of 8.01%.
Economic Model Results
In the economic model, the investigators simulated the effect of the change in HbA1c, body weight, systolic blood pressure, and cholesterol on future clinical outcomes and costs. The well-validated Economic and Health Outcomes (ECHO)-T2DM model was used to compare treatment with lifestyle measures alone versus canagliflozin 100 mg or canagliflozin 300 mg in various scenarios over 30 years, including treatment intensification, and reflecting the treatment effects of canagliflozin in the DIA3005 study.
QALYs were increased by 0.17 with canagliflozin 100 mg and by 0.21 with canagliflozin 300 mg compared with lifestyle measures only. The investigators noted that this gain in QALYs is related in part to the improvement in weight with canagliflozin. The increase in life-years was 0.12 for both doses of canagliflozin.
The cost offset per patient over 30 years was $3948 with canagliflozin 100 mg and $5428 with canagliflozin 300 mg. The reductions in myocardial infarction (MI) and nephropathy were the biggest drivers of the cost offsets (Table).
The costs for the known adverse events of urinary tract infections and female genital mycotic infections were $31 and $10 for canagliflozin 100 mg and canagliflozin 300 mg, respectively.
The relative risk reductions for macrovascular complications—cardiovascular disease composite, MI, heart disease, heart failure, stroke—ranged from 6.3% to 11.3% with canagliflozin 100 mg, and from 4.9% to 15.4% with canagliflozin 300 mg.
Retinopathy and nephropathy had relative risk reductions from 6.2% and 23.5% with canagliflozin 100 mg and 8.0% to 36.5% with canagliflozin 300 mg.