Pharmacokinetics of mirodenafil and its two metabolites, SK3541 and SK3544, in spontaneously or DOCA-salt-induced hypertensive rats

A review of the efficacy and safety of mirodenafil in the management of erectile dysfunction

Erectile dysfunction (ED) is a common disorder that can jeopardize quality of life and the partnership of patients and their sexual partners. The advent of oral phosphodiesterase type 5 inhibitors (PDE5Is) has revolutionized a treatment for ED, and they are recognized as the first-line therapy for ED, regardless of its etiology. Mirodenafil, a second-generation PDE5I, has biochemical profiles such as high affinity for PDE5 and high selectivity for PDE5 over other PDE isoforms, compared to other existing PDE5Is such as sildenafil, vardenafil and tadalafil. Available evidence has suggested that doses of 50 and 100 mg mirodenafil effectively improve ED [with improvements in the erectile function domain of the International Index of Erectile Function (IIEF-EF) scores, positive responses to questions 2 of the Sexual Encounter Profiles (SEP2) and questions 3 of the Sexual Encounter Profiles (SEP3): 7.6-11.6 points, 27.72-38.98% and 44.20-67.33%, respectively] in a broad range of patient populations with ED of a variety of underlying etiologies, severities and ages, without any serious treatment-related adverse effects. In the treatment of diabetic ED, a traditionally difficult-to-treat population, 100 mg mirodenafil has been reported to offer favorable efficacy (with improvements in the IIEF-EF scores, and positive responses to the SEP2 and the SEP3: 9.3 points, 36.1% and 61.8%, respectively) and tolerability (mild adverse effects of less than 19.6%), which are comparable with results from clinical studies on other PDE5Is. Mirodenafil appears to be effective, safe and well tolerated in men with both ED and hypertension or lower urinary tract symptoms (LUTS)/benign prostatic hyperplasia (BPH) who are taking concomitant antihypertensive medications or α1-blockers. Furthermore, recent evidence has indicated that mirodenafil may be a potential option for chronic dosing in the treatment of ED despite its short half-life (T 1/2). Most of the available clinical studies have reported that adverse effects (up to 53.7%) caused by 50 and 100 mg mirodenafil are mild or moderate in severity, with headache (1.8-14.8%) and flushing (6.7-24.1%) being the most common. Due to the pharmacodynamic profiles of mirodenafil, its tolerability is expected to be somewhat better than those of the other PDE5Is. However, further well designed studies with larger cohorts of different ethnicities, flexible dosing schedules and long-term follow up are necessary to confirm the favorable efficacy and tolerability profiles of mirodenafil for the treatment of ED.

Mirodenafil for the treatment of erectile dysfunction: a systematic review of the literature

Phosphodiesterase type 5 (PDE5) inhibitors are the most commonly used treatment for erectile dysfunction (ED). Since the launch of sildenafil, several drugs-including mirodenafil, sildenafil citrate (sildenafil), tadalafil, vardenafil HCL (vardenafil), udenafil, and avanafil-have become available. Mirodenafil is a newly developed pyrrolopyrimidinone compound, which is a potent, reversible, and selective oral PDE5 inhibitor. Mirodenafil was launched in Korea in 2007, and an orally disintegrating film of mirodenafil was developed in 2011 for benefitting patients having difficulty in swallowing tablets. This study aimed to review the pharmacokinetic characteristic profile of mirodenafil and report evidence on its efficacy in the case of ED. In addition, we reviewed randomized controlled studies of mirodenafil's daily administration and efficacy for lower urinary tract symptoms.

Pharmacokinetics of drugs in spontaneously or secondary hypertensive rats

1. Spontaneously hypertensive rats (SHRs) and deoxycorticosterone acetate-salt-induced hypertensive rats (DOCA-salt rats) have been developed as animal models for human essential (idiopathic or primary) and secondary hypertensions, respectively. 2. In order to identify pharmacokinetic changes (mainly non-renal clearance, CLNR) in 16-week-old SHRs due to hereditary characteristics and/or neither the hypertensive state itself, we reviewed the pharmacokinetics of drugs in 6- (blood pressure within a normotensive range) and 16-week-old SHRs and 16-week-old DOCA-salt rats compared with respective control rats. 3. We reviewed changes in CLNRs of drugs which are primarily metabolized via hepatic microsomal cytochrome P 450 enzymes (CYPs) based mainly on data from hypertensive rats, and present the data in terms of changes in in vitro hepatic intrinsic clearance (CLint), free fraction in plasma (fp) and hepatic blood flow rate (QH) depending on the hepatic excretion ratios of drugs. In general, changes in the CLNRs of drugs in this category were well-explained by the above-described factors. 4. We also reviewed and discussed the mechanism of urinary excretion of drugs (i.e. glomerular filtration and active renal secretion or reabsorption) in hypertensive rats.