Recent advances in insulin therapy

Increased attention to good glycaemic control in diabetic patients has encouraged more intensive use of insulin. To help achieve a steady ‘basal’ insulin supply, a new long-acting insulin analogue glargine (Lantus®) has been introduced. This provides a flatter ‘peakless’ circulating concentration of insulin than protamine (isophane) and lente insulins, facilitating dose escalation with reduced risk of hypoglycaemia. Another long-acting insulin analogue detemir (Levemir®) is advanced in development. Intensive insulin therapy requires ‘top-ups’ to coincide with mealtimes. The recently introduced rapid-acting monomeric analogues, lispro and aspart, are particularly useful in this respect. The monomeric analogues are quickly absorbed and short acting: hence they reduce post-prandial glucose excursions (which have been ascribed especial cardiovascular risk) with less risk of hypoglycaemia than conventional short-acting insulin. Premixed rapid-intermediate acting mixtures of monomeric analogues with protamine are also available. Continuous subcutaneous insulin infusion is receiving increased use as the pump technology advances, mainly incorporating the monomeric insulin analogues. Inhaled insulins continue in development, and various oral insulin formulations have entered clinical trials.