Developments in administration of growth hormone treatment: focus on Norditropin® Flexpro®

Recombinant human growth hormone is used for the treatment of growth failure in children and metabolic dysfunction in adults with growth hormone deficiency. However, conventional growth hormone therapy requires daily subcutaneous injections that may affect treatment adherence, and subsequently efficacy outcomes. To enhance potential treatment adherence, improved ease of use of growth hormone delivery devices and long-acting growth hormone formulations are now being developed. Flexpro(®), approved by the US Food and Drug Administration in March 2010, is the most recent pen device developed by Novo Nordisk A/S to deliver Norditropin(®). It is a multidose, premixed, preloaded, disposable pen device that requires relatively less force to inject and does not require refrigeration after initial use. Dose adjustments can be optimized by small dose increments of the pen delivery device at 0.025 mg, 0.05 mg and 0.1 mg. In addition, for patients with needle anxiety, NovoFine(®) needles, some of the shortest and thinnest available, and Autocover(®), which hides the needle during injections, can be used with the Flexpro pen device. This article reviews the Norditropin Flexpro pen device in the context of other growth hormone delivery devices, sustained-release growth hormone formulations in development, and future prospects.