The NICE clinical guideline on type 1 diabetes (which is currently being updated; publication date to be confirmed) recommends that basal insulin supply for adults should be provided by NPH (isophane) insulin or a long-acting insulin analogue. The guideline refers specifically to the long-acting insulin analogue, insulin glargine. It does not mention insulin detemir or insulin degludec because these were not available when the guideline was produced. These insulins will be included in the update of the NICE clinical guideline on type 1 diabetes.
Regarding the choice of insulin therapy, there is little difference between the long-acting insulin analogues that have been available for some time (insulin glargine and insulin detemir) and NPH (isophane) insulin for lowering HbA1c levels in type 1 diabetes. Compared with NPH (isophane) insulin, both these long-acting insulin analogues have been associated with statistically significantly lower rates of some, but not all, measures of hypoglycaemia in people with type 1 diabetes (CADTH Technology Overview 2010). The NICE clinical guideline on type 1 diabetes recommends that a long-acting insulin analogue should be used when:
nocturnal hypoglycaemia is a problem on NPH (isophane) insulin
morning hyperglycaemia on NPH (isophane) insulin results in difficult daytime blood glucose control
rapid-acting insulin analogues are used for mealtime blood glucose control.
Based on the results of the studies by Heller et al. (2012) and Mathieu et al. (2013), insulin degludec is likely to be marketed as a basal insulin for type 1 diabetes with potential benefits in reducing nocturnal hypoglycaemia (Ratner et al. 2013). However, the limitations of the study (discussed in the section on evidence strengths and limitations) need to be considered. The absolute difference in nocturnal hypoglycaemic rates from insulin glargine was statistically significant but small in absolute terms (between 1.4 and 4 episodes per patient per year). There is also no comparison with NPH (isophane) insulin, no patient oriented efficacy outcome data and no information on the efficacy or safety of insulin degludec over longer than the two year data currently available.
The concerns over a possible risk of medication errors with the double-strength 200 units/ml formulation also need to be considered. The Medicines and Healthcare Products Regulatory Agency has issued advice to minimise the risk of medication errors associated with this higher strength formulation, a 200 units/ml prefilled pen device (see the section on safety for more information; Drug Safety Update April 2013).
The Health and Social Care Information Centre report, Prescribing for diabetes in England - 2005-2006 to 2011-2012, stated that the net ingredient cost of insulin therapy in primary care in 2011/12 was £314.7 million: a growth of 42.5% from 2005/6 to 2011/12. In the year to September 2012, 1.3 million items of insulin glargine were prescribed at a cost of nearly £78 million, and just over 650,000 items of insulin detemir at a cost of £41 million. This compared with 370,000 items of NPH (isophane) insulin at a cost of just over £13 million (NHS Business Services Authority: personal communication July 2013).
The cost of insulin degludec 100 units/ml is £72.00 for 5×3 ml cartridges or pre-filled pens. This is more expensive than similar formulations of insulin glargine and insulin detemir, which are £41.50 and £42.00 respectively. NPH (isophane) insulin formulations are about half the cost of insulin glargine or detemir, at between £17.50 and £22.90.
The manufacturer has estimated an uptake of 5%, 10% and 15% of the eligible population in years 1, 2 and 3 respectively. It has defined the eligible population as adults (18 years or over) with type 1 diabetes currently on a basal long-acting insulin analogue (not basal NPH [isophane] insulin). Based on these estimates, for a population of 100,000 patients, this translates to the use of insulin degludec in 11 patients in year 1, 22 patients in year 2 and 33 patients in year 3 (Novo Nordisk: personal communication August 2012).
Estimated usage in type 2 diabetes is given in the evidence summary on insulin degludec in type 2 diabetes.