A cost-utility analysis of long-acting insulin analogues (detemir, glargine and degludec) for the treatment of adult type 1 diabetes in South Africa.

Background: Type 1 Diabetes Mellitus (T1DM) is a life-threatening condition that is managed with administered insulin. Intermediate- to long-acting insulin represents the basal insulin constituent of the total insulin used in treating T1DM. In South Africa, intermediate-acting Neutral Protamine Hagedorn (NPH) insulin has been the mainstay basal insulin recommended in the public sector, despite the availability of newer (ultra) long-acting insulin analogues. A cost-utility analysis of the newer long-acting insulin analogues insulins degludec, glargine U100, glargine U300 and detemir in comparison to current practice (NPH insulin) has yet to be performed in the South African public health sector context.

Methods: A cost-utility analysis was carried out utilising Markov modelling. Long-acting insulins degludec, glargine and detemir were compared to NPH insulin in the model. For each comparator, two Markov states were created, one in which no complications occurred and another representing severe nocturnal hypoglycaemic events. Quality-Adjusted Life Years (QALYs) gained per patient year was the health outcome assessed over a one-year time horizon.

Results: NPH insulin was the least costly and least effective; while Determir and Glargine U100 were extended and absolutely dominated respectively. The ICER for Glargine U300 in comparison to NPH was USD 40,104.91 per QALY gained, while Degludec was USD 64,831.20 per QALY gained in comparison to Glargine U300.

Conclusions: The ICERs of long acting insulins were considerably higher than South Africa's indicative cost-effectiveness threshold. The status quo of NPH insulin in the management of T1DM in adults remains the most cost-effective option for the South African public health sector.