Cost-Effectiveness of Low-Dose Antithymocyte Globulin Versus Other Immunotherapies for Treatment of New-Onset Type 1 Diabetes

Objective Several immunotherapies have shown efficacy in slowing C-peptide decline in new-onset type 1 diabetes. While most of these biologic drugs are expensive, they offer the opportunity to reduce downstream disease management costs and risk of complications. The objective of this study is to examine the cost-effectiveness of immunotherapies versus no treatment for patients with new-onset type 1 diabetes. Methods Using Markov microsimulation modelling and efficacy data from immunotherapy trials, we examined the cost-effectiveness of six immunotherapies for new-onset type 1 diabetes, namely, low-dose (2.5mg/kg) anti-thymocyte globulin (ATG), high-dose (6.5mg/kg) ATG, abatacept, alefacept, rituximab and teplizumab, versus no treatment. Effectiveness was measured by quality-adjusted life-years (QALYs). Costs were estimated from a health system perspective. Results Low-dose ATG treatment saves US$10,270, on average, over a patient's lifetime and generates 0.09 additional QALYs compared with no treatment. These cost savings arise as low-dose ATG generates downstream savings in disease management costs that more than offset its cost. In contrast, treatment with other immunotherapies yields smaller QALY gains (0.02-0.05 additional QALYs) and increases lifetime costs by US$9,500-US$168,380 relative to no treatment, with incremental cost-effectiveness ratios that exceed the willingness-to-pay threshold of US$100,000 per QALY. Conclusions Low-dose ATG treatment is both less costly and more effective relative to other immunotherapies and no treatment for new-onset type 1 diabetes.