Delivery of intracavernosal therapies using needle-free injection devices

Abstract

ED affects a significant proportion of males worldwide. With an ever-aging population the prevalence of ED is predicted to double in the next decade. Oral PDE-5 inhibitors are the first-line treatment for ED and have revolutionised its management. These agents are however ineffective in some men. Intracavernosal injection (ICI) of vasoactive agents is an effective second-line therapy for ED. Despite proven efficacy, needle phobia and anxiety with self-needling limit the use of intracavernosal (IC) therapies. Needle-free injection (NFI) devices allow delivery of parenteral therapies through the skin, without a needle. Although these devices have been available for decades, early studies investigating their use for ICI showed inferiority compared to standard needle-tip syringe delivery. Advances in engineering of these systems have lead to functional improvements of many aspects of fluid delivery. Our research demonstrates that modern NFI devices are better equipped to deliver ICI, and, in the cadaver models examined, achieved successful IC delivery. These findings support the potential feasibility of NFI devices to deliver ICI, and may broaden the utility of these devices to patients who refuse or discontinue IC therapy because of needle phobia or other issues with standard needle-tip syringes.