Phosphodiesterase 5 inhibitors: preclinical and early-phase breakthroughs for impotence treatments

Introduction Erectile dysfunction (ED) is a condition that affects millions of men worldwide and is characterized by the inability to achieve or maintain an erection for satisfactory sexual performance. There are numerous treatment options for ED, including medications, mechanical assist devices, and surgical management; however, first-line treatment is usually a phosphodiesterase 5 (PDE5) inhibitor. There is a growing interest in developing novel, efficacious PDE5 inhibitors that provide better quality, safety, and tolerability profiles with less adverse effects. Our review of udenafil, mirodenafil, youkenafil, lodenafil, and SLx-2101 analyzes the safety, efficacy, and pharmacokinetic properties of these new ED drugs.