pyrimidinones and mirodenafil

To systematically review evidence on the efficacy and safety of mirodenafil treatment in erectile dysfunction (ED) from randomised controlled trials.. We searched PubMed, Embase and the Cochrane Library database up to March 2013. Two authors independently assessed study quality and extracted data. All data were analyzed using RevMan 5.0. Outcome measures assessed were the International Index of Erectile Function (IIEF), erectile function domain (EFD) score (primary), the Sexual Encounter Profile questions 2 and 3, and the response to the Global Assessment Questionnaire and adverse effects (secondary).. A total of 374 participants from three randomized controlled trials were identified in this meta-analysis. After 12 weeks treatment, mirodenafil was found to be more effective than placebo, and tolerability was good. The pooled results showed that the IIEF EFD score for 100 mg mirodenafil group was higher than placebo group (MD = 8.13, 95%CI: 6.64-9.61, p < 0.00001) and the mirodenafil group was also higher than placebo group in the changes from baseline for the IIEF EFD score (MD = 7.32, 95%CI: 5.56-9.07, p < 0.00001), respectively. The most common drug-related adverse events were flushing and headache (mirodenafil versus placebo: 15.8% versus 3.2%, 3.1% versus 0%; respectively).. This meta-analysis suggested that mirodenafil is effective and well-tolerated therapy for ED.

Topics: Double-Blind Method; Erectile Dysfunction; Humans; Male; Multicenter Studies as Topic; Penile Erection; Phosphodiesterase 5 Inhibitors; Pyrimidinones; Randomized Controlled Trials as Topic; Severity of Illness Index; Sulfonamides; Treatment Outcome

Erectile dysfunction (ED) is an important worldwide health issue that has a significant negative impact on the quality of life and life satisfaction of both the affected individual and his partner. Here we review the prevalence of ED in Asia, associated factors that may influence sexual attitudes and sexual behaviours, and randomized clinical trials (RCTs) of phosphodiesterase-5 (PDE-5) inhibitors to evaluate the clinical efficacy and safety of PDE-5 inhibitors in Asian men. We searched for English-language articles in MEDLINE and PubMed from January 2000 to September 2010. Our results showed that the overall reported prevalence rate of ED in Asia ranged widely, from 2% to 88%. This finding indicates that ED is a common and major health problem in this region. However, sociocultural and economic factors in Asia prevent people from seeking and obtaining appropriate medical care. We found reports on five kinds of PDE-5 inhibitors for the management of ED: sildenafil, vardenafil, tadalafil, udenafil and mirodenafil. The results of RCTs showed that these five PDE-5 inhibitors are more effective than placebo in improving erectile function in Asian men with ED and that these drugs have similar efficacy and safety profiles.

Topics: Adult; Aged; Asia; Carbolines; Cyclic Nucleotide Phosphodiesterases, Type 5; Drug-Related Side Effects and Adverse Reactions; Erectile Dysfunction; Humans; Imidazoles; Male; Middle Aged; Phosphodiesterase 5 Inhibitors; Piperazines; Prevalence; Purines; Pyrimidines; Pyrimidinones; Randomized Controlled Trials as Topic; Sildenafil Citrate; Sulfonamides; Sulfones; Tadalafil; Triazines; Vardenafil Dihydrochloride

We aimed to evaluate whether changes in urinary and sexual function can influence health-related quality of life.. Out of 54 recruited patients, 36 were enrolled, and data for 30 participants with erectile dysfunction were available. At baseline and after 1 and 2 months, each participant completed the International Index of Erectile Function (IIEF-15), the International Prostate Symptom Score (IPSS) and the Medical Outcomes Study Short-Form 36-Item Health Survey (SF-36). Uroflowmetry, post-voiding residual volume and the nocturnal penile tumescence (NPT) test were performed at baseline and at the study's conclusion.. Compared with baseline, the IPSS, IIEF-15, peak urinary flow rate, NPT parameters and mental component of the SF-36 exhibited significant improvement at the study's conclusion. Among the symptomatic parameters, the changes in the storage and erectile function parameters contributed significantly to the change in the mental component score on the SF-36 (p = 0.007, R(2) = 0.502).. The daily administration of low-dose mirodenafil (50 mg) produced improvements in urinary and erectile function with or without sexual stimulation. Furthermore, this therapy enhanced the mental component of health-related quality of life by improving storage and erectile symptoms.

Topics: Adult; Erectile Dysfunction; Humans; Lower Urinary Tract Symptoms; Male; Middle Aged; Penile Erection; Phosphodiesterase 5 Inhibitors; Prospective Studies; Prostate; Pyrimidinones; Quality of Life; Sulfonamides; Surveys and Questionnaires; Treatment Outcome; Urinary Tract; Urodynamics

There is partial evidence to support the use of phophodiesterase-5 inhibitor (PDE5-I) for the treatment of premature ejaculation (PE).. We compared on-demand dosing of dapoxetine alone and combined with mirodenafil in subjects with lifelong PE and without erectile dysfunction (ED).. Our prospective, randomized, double-blind, placebo-controlled, multicenter trial enrolled 118 subjects with lifelong PE without ED. PE was diagnosed using Diagnostic and Statistical Manual of Mental Disorders, fourth edition, text revision. Patients were divided into two groups: dapoxetine 30 mg plus placebo (group A, n=56) and dapoxetine 30 mg plus mirodenafil 50 mg (group B, n=62).. During 12 weeks, intravaginal ejaculatory latency time (IELT) and the time from foreplay to beginning intercourse (FTIT) with a stopwatch, and Premature Ejaculation Profile (PEP) were measured. Overall sexual act time (OSAT; sum of FTIT and IELT) was calculated. Any treatment-emergent adverse events (TEAEs) were also recorded.. Over 12 weeks, IELT, OSAT, and PEP index score significantly improved in group B compared with group A (increased geometric mean IELT in group A and B=3.6 and 6.1 minutes, P=0.026; increased geometric mean OSAT in group A and B=5.5 and 9.9 minutes, P=0.012; increased median PEP index score in group A and B=1.0 and 1.3, P=0.046). However, there was no significant difference between two groups with respect to improvement of FTIT (P=0.147). TEAEs did not differ between groups (all P>0.05), and there was no serious adverse event in any subjects.. Low dose of dapoxetine combined with mirodenafil showed better results in terms of IELT, OSAT, and PEP index score, and similar TEAEs, compared with that of dapoxetine only. Our results support the suggestion that the PDE5-Is have a potential role in the treatment of PE without ED.

Topics: Adult; Aged; Benzylamines; Double-Blind Method; Humans; Male; Middle Aged; Naphthalenes; Phosphodiesterase 5 Inhibitors; Placebos; Premature Ejaculation; Prospective Studies; Pyrimidinones; Selective Serotonin Reuptake Inhibitors; Sulfonamides; Treatment Outcome

We evaluated the improvement in erectile dysfunction and lower urinary tract symptoms as well as the safety of once daily administration of 50 mg mirodenafil in men with erectile dysfunction.. A total of 226 patients visited for treatment of erectile dysfunction and were recruited for the study. Of these men 180 met the study inclusion criteria after completing a 2-week screening period (visit [V]1). The patients were randomly allocated into 2 groups. Group 1 (90 patients) received 50 mg mirodenafil once daily and group 2 (90 patients) received a placebo daily. Blood pressure, heart rate, IIEF-5 (5-item version of the International Index of Erectile Function), and SEP (Sexual Encounter Profile) questions 2 and 3 were assessed at 4 (V2), 8 (V3) and 12 weeks after the start of treatment (V4). I-PSS (International Prostate Symptom Score), maximal flow rate and post-void residual volume were also assessed for the evaluation of lower urinary tract symptoms.. Of the 180 patients 71 in group 1 and 63 in group 2 completed the 12-week clinical trial. IIEF-5 and I-PSS significantly improved in group 1 (p <0.001 for both). Facial flushing was the most common adverse effect, followed by headaches. Notably there were no statistically significant differences in either of the variables related to the cardiovascular system.. Once daily administration of 50 mg mirodenafil was efficacious and safe for the treatment of erectile dysfunction and lower urinary tract symptoms.

Topics: Administration, Oral; Adult; Dose-Response Relationship, Drug; Double-Blind Method; Drug Administration Schedule; Erectile Dysfunction; Humans; Male; Middle Aged; Penile Erection; Phosphodiesterase 5 Inhibitors; Pyrimidinones; Sulfonamides; Treatment Outcome; Young Adult

A high-sensitivity LC/MS/MS method was developed and validated for the simultaneous determination of mirodenafil and its major metabolite, SK-3541, in human plasma. Mirodenafil, SK-3541, and udenafil as an internal standard were extracted from plasma samples with methyl tert-butyl ether. Chromatographic separation was performed on a Luna phenyl-hexyl column (100 × 2.0 mm) with an isocratic mobile phase consisting of 5 mM ammonium formate and ACN (23:77, v/v) at a flow rate of 0.35 mL/min. Detection and quantification were performed using a mass spectrometer in selected reaction monitoring mode with positive ESI at m/z 532.3 → 296.1 for mirodenafil, m/z 488.1 → 296.1 for SK-3541, and m/z 517.3 → 283.2 for udenafil. The calibration curves were linear over a concentration range of 2-500 pg/mL using 0.5 mL plasma for the microdose of mirodenafil (100 μg). Analytical method validation of the clinical dose (100 mg), with a calibration curve range of 2-500 ng/mL using 0.025-mL plasma, was also conducted. The other LC-MS/MS conditions were similar to those used for the microdosing. Each method was applied successfully to pharmacokinetic studies after a microdose or clinical dose of mirodenafil to six healthy Korean male volunteers.

Topics: Adult; Chromatography, High Pressure Liquid; Drug Dosage Calculations; Erectile Dysfunction; Humans; Male; Pyrimidines; Pyrimidinones; Sensitivity and Specificity; Sulfonamides; Tandem Mass Spectrometry; Young Adult

Both mirodenafil, a phosphodiesterase type 5 inhibitor for the treatment of erectile dysfunction, and tamsulosin, a selective α(1A)-adrenergic receptor antagonist for the treatment of benign prostatic hyperplasia, have mild vasodilational effects.. The aim of this study was to investigate the effect of mirodenafil on the hemodynamics of healthy volunteers who were administered tamsulosin.. Healthy, Korean normotensive male volunteers were enrolled in a randomized, placebo-controlled, double-blind, 2-sequence, 2-period crossover study. Mirodenafil 100 mg or placebo was administered orally after pretreatment with tamsulosin 0.2 mg once daily for 7 days in each period, with a 1-week washout period. Blood pressure (BP) and pulse rate (PR) in supine and standing positions were measured repeatedly before and until 24 hours after the administration of mirodenafil or placebo. The mean differences from the baseline values of the maximum changes of BP and PR, which were measured at 4 and 24 hours, were analyzed by using a mixed-effects model.. Eighteen subjects (mean [SD] age, 26.8 [3.9] years; weight, 65.5 [7.0] kg) were administered any trial medication, and 16 of them completed the study. For 4 hours/24 hours after mirodenafil administration, the mean maximal changes from baseline versus placebo in supine systolic BP, diastolic BP, and PR were -1.0 mm Hg (95% CI, -4.2 to 2.2) (P = 0.53)/-1.2 mm Hg (95% CI, -5.3 to 2.9) (P = 0.56), -2.1 mm Hg (95% CI, -4.6 to 0.4) (P = 0.10)/-1.1 mm Hg (95% CI, -3.9 to 1.6) (P = 0.39), and 7.2 beats/min (95% CI, 4.7 to 9.6) (P < 0.05)/4.8 beats/min (95% CI, 1.4 to 8.1) (P < 0.05), respectively. Those changes in a standing position were -4.0 mm Hg (95% CI, -8.9 to 0.9) (P = 0.10)/-4.3 mm Hg (95% CI, -10.0 to 1.5) (P = 0.13), -1.1 mm Hg (95% CI, -4.9 to 2.7) (P = 0.54)/-1.9 mm Hg (95% CI, -5.5 to 1.7) (P = 0.27), and 10.7 beats/min (95% CI, 4.4 to 16.9) (P < 0.05)/6.0 beats/min (95% CI, 0.7 to 11.3) (P < 0.05), respectively. A total of 33 adverse events (AEs) were reported in 9 of 18 subjects. The number of subjects with AEs (P = 0.13) and the number of AEs (P = 0.26) were not significantly different between the 2 groups. The most common AEs were vasodilational symptoms, such as nasal congestion, headache, and flushing.. The coadministration of mirodenafil 100 mg did not induce a significant decrease in BP when associated with an increase in PR in these healthy male Korean volunteers administered tamsulosin 0.2 mg compared with placebo. (Clinical Trial Registry, http://cris.cdc.go.kr/cris/en/: KCT0000117).

Topics: Administration, Oral; Adrenergic alpha-1 Receptor Antagonists; Adult; Blood Pressure; Cross-Over Studies; Double-Blind Method; Drug Interactions; Heart Rate; Hemodynamics; Humans; Male; Middle Aged; Phosphodiesterase 5 Inhibitors; Pyrimidinones; Republic of Korea; Sulfonamides; Tamsulosin; Vasodilator Agents; Young Adult

Mirodenafil is a newly developed selective phosphodiesterase type 5 (PDE5) inhibitor for the treatment of erectile dysfunction (ED).. To evaluate the efficacy, safety and tolerability of mirodenafil in the treatment of ED in Korean men with diabetes.. A multicenter, randomized, double-blind, placebo-controlled, parallel-group, fixed-dose study was conducted with 112 subjects who were randomized to either placebo or mirodenafil 100 mg on demand for 12 weeks.. Primary efficacy variable was the erectile function (EF) domain scores of the International Index of Erectile Dysfunction (IIEF) questionnaire. Secondary efficacy variables included change in the scores of IIEF question 3 and 4 (IIEF Q3 and Q4) from baseline, change in all domain scores in the IIEF from baseline, Sexual Encounter Profile questions 2 and 3 (SEP2 and SEP3), the Global Assessment Question (GAQ) and the Life Satisfaction Checklist (LSC).. After 12 weeks of treatment, mirodenafil group showed significantly greater change in the IIEF-EF domain score from baseline compared with the placebo group (9.3 vs. 1.4, P < 0.0001). The changes from baseline in the mirodenafil group in IIEF Q3 (1.7 vs. 0.4, P < 0.0001) and Q4 (1.7 vs. 0.3, P < 0.0001) were higher compared with the placebo group. Differences between the mirodenafil and placebo groups were significant in the SEP2 (82.0% vs. 55.2%, P = 0.0003), SEP3 (68.9% vs. 22.3%, P < 0.0001). Difference in GAQ "YES" responses was also significant (76.9% vs. 19.1%, P < 0.0001). Normal EF domain scores (≥ 26) at study end were achieved by 32.7% and 9.4% in the mirodeniafl and placebo groups, respectively (P = 0.0031). As for the LSC scores, the mirodenafil group showed significantly greater improvements in sexual life and partner relationship than the placebo group. Most treatment-associated AEs were mild that resolved spontaneously.. Mirodenafil is an effective and well-tolerated agent for the treatment of diabetic patients with ED in Korea.

Topics: Administration, Oral; Aged; Cross-Cultural Comparison; Diabetic Angiopathies; Double-Blind Method; Humans; Impotence, Vasculogenic; Male; Middle Aged; Penile Erection; Phosphodiesterase 5 Inhibitors; Pyrimidinones; Republic of Korea; Sulfonamides

Mirodenafil is a recently developed oral phosphodiesterase type 5 inhibitor, which was observed to significantly improve erectile function and was well tolerated in men with broad-spectrum erectile dysfunction (ED).. To investigate the efficacy and safety of mirodenafil treatment compared with placebo in men taking at least one antihypertensive medication.. A multicenter, double-blind, placebo-controlled, parallel group, fixed-dose study was conducted with 109 subjects who were randomized to placebo or mirodenafil 100 mg for 12 weeks on an "as needed" basis.. The primary efficacy measures were the changes from baseline in sum of scores on International Index of Erectile Function-erectile function domain (IIEF-EF) questions 1 to 5 and 15 with treatment. The secondary efficacy measures included scores on IIEF question 3 and 4 (Q3 and Q4), all domain scores of IIEF, and Sexual Encounter Profile Question 2 and 3 (SEP2 and SEP3) along with responses to Global Assessment Question (GAQ) and Life Satisfaction Checklist (LSC). The safety assessments included laboratory tests, vital signs, 12-lead electrocardiogram recordings, and patients' reporting of adverse events.. The mirodenafil group showed significantly greater increase in IIEF-EF scores at 12 weeks compared with the placebo group (9.35 ± 6.86 vs. 2.66 ± 6.44, P<0.001). The mirodenafil group also demonstrated significantly greater improvement in scores of IIEF Q3 and Q4, other four domains of IIEF, SEP2, SEP3, and LSC along with percentages of patients responding positively to GAQ compared with the placebo group. During the study, no clinically significant changes were observed regarding blood pressure, heart rate, electrocardiographic findings, or laboratory values. Facial flushing and headache were the most common treatment-associated adverse events, which were mild or moderate in severity, resolving spontaneously.. Mirodenafil was effective and safe in men with ED concomitantly taking antihypertensive medications.

Topics: Antihypertensive Agents; Blood Pressure; Double-Blind Method; Electrocardiography; Erectile Dysfunction; Flushing; Headache; Heart Rate; Humans; Hypertension; Male; Middle Aged; Phosphodiesterase 5 Inhibitors; Pyrimidinones; Sulfonamides

Mirodenafil is a phosphodiesterase type 5 (PDE-5) inhibitor developed for the treatment of erectile dysfunction. Mirodenafil has the possibility of being administered with alcohol.. This study assessed the hemodynamic effects and pharmacokinetic properties of mirodenafil administered with alcohol.. This single-dose, randomized-sequence, open-label, crossover study was conducted in healthy male volunteers at the Clinical Trials Center, Seoul National University Hospital, Seoul, Korea. Volunteers were randomly allocated to 1 of 3 randomized-sequence groups, each of which consisted of 3 administration phases, each separated by a 1-week washout period: oral mirodenafil 100 mg, alcohol 0.5 g/kg, and both. Vital signs (systolic blood pressure [SBP], dia-stolic BP [DBP], and pulse rate) were measured before (baseline) and at 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 5, 6, 8, 12, and 24 hours after administration. Because volunteers were given a standardized meal at 4 hours after mirodenafil and/or alcohol administration, hemody-namic results were assessed using the maximum decrease from baseline during a period of up to 4 hours after administration. For pharmacokinetic assessment, serial blood samples were collected before (baseline) and at 0.5, 1, 1.25, 1.5, 2, 2.5, 3, 4, 6, 8, 12, and 24 hours after administration. Tolerability was assessed using monitoring of adverse events (AEs), clinical laboratory parameters, and results of 12-lead electrocardiography.. A total of 20 subjects participated in the study (mean [range] age, 25.5 years [20-41 years]; weight, 69.8 kg [57.4-87.2 kg]; and height, 174.7 cm [168-186 cm]). Up to 4 hours after the administration of mirodenafil, alcohol, and mirodenafil + alcohol, the mean (SD) maximum decreases in SBP were 8.5 (3.5), 13.5 (7.8), and 15.1 (6.7) mm Hg, respectively, and the maximum decreases in DBP were 6.4 (4.8), 13.3 (7.4), and 13.8 (5.2) mm Hg. Simultaneous administration of mirodenafil + alcohol was associated with additional mean (95% CI) decreases in SBP and DBP of 1.7 mm Hg (-6.0 to 2.6 mm Hg) and 0.6 mm Hg (-4.7 to 3.6 mm Hg) compared with alcohol alone. Pharmacokinetic parameters of mirodenafil were not significantly different when the drug was administered with or without alcohol. The mean (SD) AUC(0-t) values were 842.0 (434.7) ng/mL/h with mirodenafil and 833.4 (398.2) ng/mL/h with mirodenafil + alcohol. The most common AEs considered at least possibly related to study drug were nasal congestion (7 subjects [35%]), headache (3 [15%]), nausea (1 [5%]), and hiccups (1 [5%]).. The concurrent administration of mirodenafil with alcohol was not associated with clinically significant hemodynamic changes in these healthy male volunteers in Korea. The pharmacoki-netics of mirodenafil were not significantly altered by this concurrent administration. Mirodenafil administered with alcohol had a tolerability profile comparable to that of mirodenafil alone.

Topics: Adult; Area Under Curve; Blood Pressure; Cross-Over Studies; Drug Interactions; Electrocardiography; Ethanol; Hemodynamics; Humans; Korea; Male; Phosphodiesterase 5 Inhibitors; Phosphodiesterase Inhibitors; Pyrimidinones; Sulfonamides; Time Factors; Young Adult

Mirodenafil, a phosphodiesterase 5 inhibitor reported to be effective in the treatment of erectile dysfunction, is metabolized by cytochrome P450 (CYP) 3A4 to the active metabolite N-dehydroxyethyl mirodenafil. Mirodenafil may have drug-drug interactions with ketoconazole and/or rifampicin.. The aim of this study was to investigate the effects of a potent inhibitor (ketoconazole) and inducer (rifampicin) of the CYP3A4 isozyme on the pharmacokinetics of mirodenafil to meet the regulatory requirements for the marketing of mirodenafil in Korea.. An open-label, 1-sequence, 3-period, 3-treatment crossover study was conducted over 22 days in healthy Korean male volunteers. Each subject received 100 mg of mirodenafil in each of 3 study periods: mirodenafil alone (period 1); mirodenafil after pretreatment with ketoconazole 400 mg once daily for 3 days (period 2); and mirodenafil after pretreatment with rifampicin 600 mg once daily for 10 days (period 3). Serial blood samples were collected for pharmacokinetic analysis after the administration of mirodenafil in each study period. Plasma concentration-time data for mirodenafil and its major metabolite, N-dehydroxyethyl mirodenafil, were determined using LC-MS/MS and analyzed by a noncompartmental method. The results for mirodenafil coadministration with either ketoconazole or rifampicin were compared with those for mirodenafil alone. Adverse events (AEs) were identified by asking general health-related questions of the subjects, by physical examination, and by subject self-report throughout the study period.. Nineteen subjects were enrolled (mean [SD] age, 23.2 [2.76] years [range, 19-29 years]; weight, 69.3 [6.50] kg [range, 61.0-84.0 kg]; body mass index, 22.4 [1.77] kg/m(2) [range, 20.0-26.0 kg/m(2)]) and 18 subjects completed the study. One subject discontinued the study due to protocol violation and was replaced. The AUC(0-infinity) of mirodenafil increased 5.04-fold (90% CI, 3.78-6.72) and the metabolic ratio decreased 0.21-fold after pretreatment with ketoconazole compared with mirodenafil alone. After pretreatment with rifampicin, the AUC(0-infinity) of mirodenafil decreased 0.03-fold (90% CI, 0.02-0.05) and the metabolic ratio increased 2.9-fold. Twelve cases of headache, 6 of nasal congestion, 2 of feeling hot, 2 of epistaxis, and 1 each of dizziness, nausea, and somnolence were considered to be related to administration of mirodenafil. Twenty-eight AEs were reported in period 2 (in 68.4% of subjects), during which systemic exposure to mirodenafil was highest, whereas 7 AEs were reported in period 1 (in 31.6% of subjects) and 5 AEs in period 3 (in 16.7% of subjects).. In these healthy Korean male volunteers, the coadministration of ketoconazole and rifampicin resulted in significant changes in systemic exposure to mirodenafil.

Topics: Adult; Asian People; Biological Availability; Biotransformation; Chromatography, Liquid; Cross-Over Studies; Cytochrome P-450 CYP3A; Cytochrome P-450 CYP3A Inhibitors; Drug Interactions; Enzyme Induction; Enzyme Inhibitors; Humans; Ketoconazole; Korea; Male; Phosphodiesterase 5 Inhibitors; Phosphodiesterase Inhibitors; Pyrimidinones; Rifampin; Sulfonamides; Tandem Mass Spectrometry; Young Adult

Mirodenafil is a newly developed oral phosphodiesterase type 5 inhibitor, currently under investigation as a treatment for erectile dysfunction (ED).. We investigated the efficacy and safety of on demand mirodenafil therapy at fixed doses (50 and 100 mg) in Korean men with a broad range of ED.. A multicenter, randomized, double-blind, placebo-controlled, parallel-group, fixed-dose study was conducted with 223 subjects who were randomized to placebo or mirodenafil at fixed doses of 50 or 100 mg for 12 weeks on an "as needed" basis.. Primary efficacy measures were scores on the International Index of Erectile Function (IIEF) Question 3 (Q3) and Question 4 (Q4). Secondary efficacy measures included all domain scores of the IIEF, Sexual Encounter Profile Question 2 (SEP2), Sexual Encounter Profile Question 3 (SEP3), the Global Assessment Question (GAQ), and the Life Satisfaction Checklist (LSC). Safety assessments included laboratory tests, vital signs, physical examination, 12-lead electrocardiogram recordings, and patients' reporting of adverse events.. Mirodenafil 50 and 100 mg groups showed a significantly greater increase in IIEF Q3 (P = 0.0001, P < 0.0001, respectively) and Q4 scores (both P < 0.0001) at the end point compared with the placebo group. And mirodenafil in both doses significantly improved the scores of all five domains of the IIEF, SEP2, and SEP3 as well as the percentages of patients responding positively to the GAQ compared with the placebo group. As for LSC scores, the two mirodenafil groups showed significantly greater improvements in items regarding life as a whole, sexual life, and partner relationship than the placebo group. Most treatment-associated adverse events were of mild intensity, resolving spontaneously.. Mirodenafil, in doses of 50 or 100 mg, significantly improved erectile function and were well tolerated in a representative population of Korean men with broad-spectrum ED of various etiologies and severities.

Topics: Administration, Oral; Adult; Aged; Dose-Response Relationship, Drug; Double-Blind Method; Erectile Dysfunction; Humans; Korea; Male; Middle Aged; Patient Satisfaction; Phosphodiesterase 5 Inhibitors; Phosphodiesterase Inhibitors; Pyrimidinones; Sulfonamides; Treatment Outcome; Young Adult

Alzheimer's disease (AD) pathology is associated with complex interactions among multiple factors, involving an intertwined network of various signaling pathways. The polypharmacological approach is an emerging therapeutic strategy that has been proposed to overcome the multifactorial nature of AD by targeting multiple pathophysiological factors including amyloid-β (Aβ) and phosphorylated tau. We evaluated a blood-brain barrier penetrating phosphodiesterase 5 (PDE5) inhibitor, mirodenafil (5-ethyl-2-7-n-propyl-3,5-dihydrro-4H-pyrrolo[3,2-d]pyrimidin-4-one), for its therapeutic effects on AD with polypharmacological properties.. To evaluate the potential of mirodenafil as a disease-modifying AD agent, mirodenafil was administered to test its effects on the cognitive behaviors of the APP-C105 AD mouse model using the Morris water maze and passive avoidance tests. To investigate the mechanisms of action that underlie the beneficial disease-modifying effects of mirodenafil, human neuroblastoma SH-SY5Y cells and mouse hippocampal HT-22 cells were used to show mirodenafil-induced alterations associated with the cyclic guanosine monophosphate (cGMP)/cGMP-dependent protein kinase (PKG)/cAMP-responsive element-binding protein (CREB) pathway, apoptotic cell death, tau phosphorylation, amyloidogenesis, the autophagy-lysosome pathway, glucocorticoid receptor (GR) transcriptional activity, and the Wnt/β-catenin signaling.. Here, mirodenafil is demonstrated to improve cognitive behavior in the APP-C105 mouse model. Mirodenafil not only reduced the Aβ and phosphorylated tau burdens in vivo, but also ameliorated AD pathology induced by Aβ through the modulation of the cGMP/PKG/CREB signaling pathway, glycogen synthase kinase 3β (GSK-3β) activity, GR transcriptional activity, and the Wnt/β-catenin signaling in neuronal cells. Interestingly, homodimerization and nuclear localization of GR were inhibited by mirodenafil, but not by other PDE5 inhibitors. In addition, only mirodenafil reduced the expression levels of the Wnt antagonist Dickkopf-1 (Dkk-1), thus activating the Wnt/β-catenin signaling.. These findings strongly suggest that the PDE5 inhibitor mirodenafil shows promise as a potential polypharmacological drug candidate for AD treatment, acting on multiple key signaling pathways involved in amyloid deposition, phosphorylated tau burden, the cGMP/PKG/CREB pathway, GSK-3β kinase activity, GR signaling, and the Wnt/β-catenin signaling. Mirodenafil administration to the APP-C105 AD mouse model also improved cognitive behavior, demonstrating the potential of mirodenafil as a polypharmacological AD therapeutic agent.

Topics: Alzheimer Disease; Amyloid beta-Peptides; Animals; beta Catenin; Cyclic GMP; Disease Models, Animal; Glycogen Synthase Kinase 3 beta; Humans; Mice; Neuroblastoma; Phosphodiesterase 5 Inhibitors; Phosphorylation; Pyrimidinones; Sulfonamides; tau Proteins

To evaluate the distribution of a daily phosphodiesterase type 5 inhibitor dose (mirodenafil) in rat plasma and bladder and prostate tissue in a model of atherosclerosis-induced chronic pelvic ischemia.. Thirty-two 18-week-old male Sprague Dawley rats were divided into two groups. Group I (n = 16) comprised a chronic pelvic ischemia model treated with mirodenafil and group II (n = 16) comprised a sham-operated model also treated with mirodenafil. The mirodenafil concentrations in each organ were measured at specific time points after 14 days of daily mirodenafil administration. The drug distribution ratio of group I to group II of each organ was measured, and the bladder tissue-to-plasma and prostate tissue-to-plasma ratios were calculated.. The mean drug concentration in the bladder of the rats in group I did not differ significantly from that of group II after mirodenafil administration. In the prostate, the mean drug concentration of group I was significantly higher than that of group II at 1 and 4 hours after drug administration. The drug concentration was higher in the bladder tissue than in the prostate tissue and the bladder tissue-to-plasma ratio was significantly higher than the prostate tissue-to-plasma ratio.. Our results suggest that mirodenafil levels might be sufficient in the target tissue after daily treatment in an ischemia-induced aging model. Considering the difficulties of tissue distribution study in human subjects, the results of this investigation provided meaningful evidence of the application of daily doses of mirodenafil for treating lower urinary tract symptoms in an aging population.

Topics: Animals; Chronic Disease; Disease Models, Animal; Ischemia; Male; Pelvis; Phosphodiesterase 5 Inhibitors; Prostate; Pyrimidinones; Rats; Rats, Sprague-Dawley; Sulfonamides; Tissue Distribution; Urinary Bladder

Topics: Erectile Dysfunction; Humans; Male; Penile Erection; Pyrimidinones; Sulfonamides

In this study, the pharmacokinetics of 2 forms of mirodenafil, namely the base form and the hydrochloride salt form, were investigated in rats. The 2 forms were orally administered to rats and the plasma concentrations of mirodenafil were determined using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The mirodenafil base and hydrochloride salt forms showed similar pharmacokinetic profiles in terms of their maximum plasma concentration (Cmax) and area under the concentration-time curve (AUC). The time to peak concentration (Tmax) of the base form was slightly greater than that of the salt form, but this difference was not statistically significant. These results suggest that the mirodenafil base and hydrochloride forms are pharmacokinetically equivalent in rats, and thus the base form could be used in various mirodenafil formulations as a substitute for the existing mirodenafil hydrochloride form.

Topics: Animals; Chemistry, Pharmaceutical; Chromatography, Liquid; Male; Phosphodiesterase 5 Inhibitors; Pyrimidinones; Rats; Rats, Sprague-Dawley; Sulfonamides; Tandem Mass Spectrometry

To evaluate and compare the pharmacokinetics and tolerability of a single oral dose of mirodenafil in volunteer patients with severe renal impairment and healthy volunteers.. This open-label, single-dose, parallel group clinical study enrolled a total 12 volunteers (6 healthy volunteers and 6 volunteer patients with severe renal impairment). Each volunteer was orally administered 50 mg mirodenafil and serial blood samples were obtained after drug administration to determine the plasma concentration of mirodenafil using LC-MS/MS. The measured individual plasma concentrations were used to calculate the pharmacokinetic parameters using noncompartmental methods. Tolerability was also assessed using measurements of vital signs, clinical chemistry tests, and interviews.. All of the volunteers completed the study with no serious adverse events (AEs). A total of 4 AEs were reported, but all were of mild or moderate intensity and not considered to be related to the study drug. The geometric mean (95% CI) of the terminal half-life (t1/2β) and the apparent clearance (CL/F) values of mirodenafil were 2.2 (1.4 - 3.4) h and 127.2 (95.1 - 170.2) l/h in the volunteer patients, and 3.0 (2.1 - 4.4) h and 136.1 (74.4 - 249.2) l/h in the healthy volunteers, respectively. The geometric mean of the AUC0-t of the volunteer patients was 8% higher and the geometric mean for clearance was 7% lower compared with the healthy volunteers. However, the geometric mean of the Cmax of the volunteer patients was 38% higher than that of the healthy volunteers.. A single oral 50-mg dose of mirodenafil was well tolerated. Exposure (AUC0-t) to mirodenafil was similar in both healthy volunteers and volunteer patients with severe renal impairment and healthy volunteers.

Topics: Adult; Chromatography, Liquid; Humans; Male; Middle Aged; Phosphodiesterase 5 Inhibitors; Pyrimidinones; Renal Insufficiency; Sulfonamides; Tandem Mass Spectrometry

Hypertension is the most common comorbidity and major risk factor in patients with erectile dysfunction. The pharmacokinetics of mirodenafil, used for the treatment of erectile dysfunction, after the intravenous and oral administration (20 mg/kg) to 6-week-old rats (with blood pressure within the normotensive range) and 16-week-old spontaneously hypertensive rats (SHRs) and their age-matched control normotensive Kyoto-Wistar (KW) rats, and 16-week-old deoxycorticosterone acetate-salt-induced hypertensive rats (DOCA-salt rats) and their age-matched control Sprague-Dawley (SD) rats were compared. It was found that time-averaged renal clearance (Cl(r)) was of minor importance and that time-averaged non-renal clearance (Cl(nr)) was dominant. In both 6- and 16-week-old SHRs, the Cl(nr)s and areas under the curve (AUCs) of intravenous mirodenafil were significantly smaller and greater than those of the controls, but in 16-week-old DOCA-salt rats, they were comparable to the controls. Although the AUC of oral mirodenafil in 16-week-old SHRs was comparable to the controls, the Cl(nr)s (or total body clearances, Cls) of intravenous mirodenafil and intestinal intrinsic clearances were significantly smaller than the controls and comparable to the controls for both 6- and 16-week-old SHRs, unlike in the 16-week-old DOCA-salt rats. The above data suggest that the significantly smaller Cl(nr) and greater AUC of intravenous mirodenafil and comparable AUC of oral mirodenafil in 16-week-old SHR could be due to the hereditary characteristics of SHRs, and not due to the hypertensive state itself.

Topics: Animals; Desoxycorticosterone; Disease Models, Animal; Hypertension; Male; Pyrimidinones; Random Allocation; Rats; Rats, Inbred SHR; Rats, Inbred WKY; Rats, Sprague-Dawley; Sulfonamides

In this study, we investigated the effects of a combination of Ginkgo biloba extracts (GBE) and phosphodiesterase type 5 (PDE-5) inhibitors on the muscular tone of the corpus cavernosum and potassium channel activity of corporal smooth muscle cells. Strips of corpus cavernosum from male New Zealand white rabbits were mounted in organ baths for isometric tension studies. After contraction with 1×10⁻⁵ mol l⁻¹ norepinephrine, GBE (0.01-1 mg ml⁻¹) and mirodenafil (0.01-100 nmol l⁻¹) were added together into the organ bath. In electrophysiological studies, whole-cell currents were recorded by the conventional patch-clamp technique in cultured smooth muscle cells of the human corpus cavernosum. The corpus cavernosum was relaxed in response to GBE in a dose-dependent manner (from 0.64%±8.35% at 0.01 mg ml⁻¹ to 52.28% ± 11.42% at 1 mg ml⁻¹). After pre-treatment with 0.03 mg ml⁻¹ of GBE, the relaxant effects of mirodenafil were increased at all concentrations. After tetraethylammonium (TEA) (1 mmol l⁻¹) administration, the increased effects were inhibited (P<0.01). Extracellular administration of GBE increased the whole-cell K(+) outward currents in a dose-dependent fashion. The increase of the outward current was inhibited by 1 mmol l⁻¹ TEA. These results suggest that GBE could increase the relaxant potency of mirodenafil even at a minimally effective dose. The K(+) flow through potassium channels might be one of the mechanisms involved in this synergistic relaxation.

Topics: Animals; Ginkgo biloba; Male; Muscle Relaxation; Muscle, Smooth, Vascular; Patch-Clamp Techniques; Penis; Phosphodiesterase 5 Inhibitors; Plant Extracts; Potassium Channels; Pyrimidinones; Rabbits; Sulfonamides

Enhanced RhoA/Rho-kinase pathway plays anti-erectile role and is associated with reduced response to type 5 phosphodiesterase inhibitor (PDE5I) in diabetic animals. We tested whether adjunctive simvastatin to conventional insulin treatment would restore PDE5I-induced as well as basal erectile response in diabetic rat model of erectile dysfunction. Forty 8-week-old male Sprague-Dawley rats were equally divided into four groups, (n=10) i.e. the diabetic group (D), age-matched control (C), conventional insulin treatment (I) and adjunctive simvastatin to conventional insulin treatment (S). Following 10weeks of intraperitoneal injection of streptozotocin (STZ, 35mg/kg), the group I and S received insulin (10U NPH/day) for 4weeks. Concurrently, group S received simvastatin (20mg/kg/day). Following 14weeks of diabetes induction, basal and PDE5I (intravenous mirodenafil 1mg/kg)-elicited erectile response were assessed during cavernous nerve electrostimulation. Then, penile tissues were processed for molecular assessment. Although group I failed to restore basal and PDE5I-induced erectile response, group S showed normalized erectile responses. Furthermore, group I showed improvement of only eNOS-related pathway, whereas group S effectively controlled both eNOS-related and RhoA/Rho-kinase pathway. Conclusively, adjunctive use of simvastatin to conventional insulin treatment showed more effectiveness in restoring erectile responses of diabetic rats by controlling the RhoA/Rho-kinase pathway than conventional insulin treatment alone.

Topics: Animals; Blood Glucose; Diabetes Mellitus, Experimental; Erectile Dysfunction; Insulin; Male; Nitric Oxide Synthase Type III; Penile Erection; Phosphodiesterase 5 Inhibitors; Pyrimidinones; Rats; Rats, Sprague-Dawley; rho-Associated Kinases; rhoA GTP-Binding Protein; Simvastatin; Sulfonamides

The area under the curve (AUC) of mirodenafil after intravenous administration in diabetes mellitus induced by streptozotocin (DMIS) rats was significantly smaller (by 28.0 %) than the control value, and the AUC(SK3541)/AUC(mirodenafil) ratio was significantly greater (by 130 %) in DMIS rats. This may be explained by the significantly faster hepatic CL(int) of mirodenafil, owing to increased hepatic CYP1A, CYP2B1/2, CYP2D, and CYP3A expression, and a faster hepatic blood flow rate, compared with control values. The AUC of mirodenafil after oral administration was comparable between DMIS and control rats, possibly because of the comparable intestinal CL(int), which may be attributable to increased CYP1A2 expression and decreased CYP2D expression in the intestines of DMIS rats.

Topics: Administration, Oral; Animals; Area Under Curve; Diabetes Complications; Diabetes Mellitus, Experimental; Erectile Dysfunction; Infusions, Intravenous; Male; Pyrimidinones; Rats; Rats, Sprague-Dawley; Streptozocin; Sulfonamides

This study was performed to find which types of hepatic CYP isoforms are responsible for the metabolism of mirodenafil (a new erectogenic) and one of its metabolite, SK3541, using various hepatic CYP inducers and inhibitors in rats.. Mirodenafil at a dose of 20 mg/kg was administered intravenously to control rats and rats pretreated with various CYP inducers and inhibitors. The disappearance of SK3541 was also measured in vitro hepatic microsomes of rats with and without CYP inducer and inhibitors.. Compared to controls, in rats pretreated with 3-methylcholanthrene, orphenadrine, and dexamethasone (main inducers of CYP1A1/2, 2B1/2, and 3A1/2, respectively), the non-renal clearances (CLNRs) of mirodenafil were significantly faster (by 39.4%, 59.3%, and 63.9%, respectively). However, compared to controls, in rats pretreated with quinine and troleandomycin (main inhibitors of CYP2D subfamily and 3A1/2, respectively), the CLNRs of mirodenafil were significantly slower (by 36.1% and 33.2%, respectively). In rat hepatic microsomes spiked with furafylline, quinine, and troleandomycin (main inhibitors of CYP1A2, 2D subfamily, and 3A1/2, respectively), the intrinsic clearances (CLints) for the disappearance of SK3541 were significantly slower (by 18.4%, 35.3%, and 51.5%, respectively) than controls. Also in rat hepatic microsomes pretreated with orphenadrine (a main inducer of CYP2B1/2), the CLint for the disappearance of SK3541 was significantly faster (by 55.5%) than controls.. The above data suggest that hepatic CYP1A1/2, 2B1/2, 2D subfamily, and 3A1/2 are involved in the metabolism of both mirodenafil and SK3541 in rats.

Topics: Animals; Cytochrome P-450 Enzyme System; Enzyme Induction; Enzyme Inhibitors; Male; Microsomes, Liver; Phosphodiesterase 5 Inhibitors; Pyrimidinones; Rats; Rats, Sprague-Dawley; Sulfonamides

The objective of this work was to investigate the existence of polymorphs of SK-3530 and the transformation of crystal forms. Two crystal forms of SK-3530 have been isolated by recrystallization and characterized by differential scanning calorimetry, powder X-ray diffractometry and thermogravimetric analysis. The differential scanning calorimetry and powder X-ray diffractometry patterns of two crystal forms were different respectively. After storage of 1 month at 0% RH (silica gel, 20°C), 52% RH (saturated solution of Na(2)Cr(2)O(7)·2H(2)O/20°C) and 95% RH (saturated solution of Na(2)HPO(4)/20°C), Form 2 was not transformed to Form 1 and two forms were shown to have a good physical stability at room temperature for 1 month. In the dissolution studies in pH 6.8 buffer at 37 ± 0.5°C, the dissolution rate of Form 2 was significantly higher than that of Form 1 under 30 min.

Topics: Calorimetry, Differential Scanning; Crystallization; Phosphodiesterase 5 Inhibitors; Pyrimidinones; Solubility; Sulfonamides; Thermogravimetry; X-Ray Diffraction

The purpose of the present study was to determine sildenafil and a novel PDE-5 inhibitor, mirodenafil in the plasma and corpus cavernosum tissue of rats to compare their pharmacokinetic properties. The concentrations of mirodenafil and sildenafil in the rat plasma and corpus cavernosum tissue samples were analyzed using LC-MS/MS after a single oral administration at a dose of 40mg/kg to rats. Although the T(max), Tlambda(1/2) and MRT were not different between mirodenafil and sildenafil, the C(max) and AUC of mirodenafil were significantly higher than those of sildenafil in the plasma and corpus cavernosum tissue. Consequently mirodenafil remained longer than sildenafil in the plasma and tissue. This may provide pharmacokinetic evidence for assessment of the in vivo efficacy of mirodenafil and sildenafil.

Topics: Administration, Oral; Animals; Area Under Curve; Chromatography, Liquid; Cyclic Nucleotide Phosphodiesterases, Type 5; Fasting; Half-Life; Hydrogen-Ion Concentration; Male; Mass Spectrometry; Metabolic Clearance Rate; Molecular Structure; Molecular Weight; Penis; Phosphodiesterase Inhibitors; Piperazines; Polyethylene Glycols; Purines; Pyrimidinones; Quality Control; Random Allocation; Rats; Rats, Sprague-Dawley; Reference Standards; Reproducibility of Results; Sildenafil Citrate; Solutions; Specific Pathogen-Free Organisms; Sulfonamides; Sulfones

The pharmacokinetics of mirodenafil and its two metabolites, SK3541 and SK3544, after intravenous (5, 10, 20 and 50 mg/kg) and oral (10, 20 and 50 mg/kg) administration of mirodenafil, and the first-pass effect of mirodenafil after intravenous, oral, intraportal, intragastric and intraduodenal (20 mg/kg) administration of mirodenafil were evaluated in rats. The pharmacokinetics of mirodenafil and SK3541 were dose-dependent after both intravenous and oral administration of mirodenafil due to the saturable hepatic metabolism of mirodenafil. After oral administration of mirodenafil, approximately 2.59% of the oral dose was not absorbed, the F value was approximately 29.4%, and the hepatic and gastrointestinal first-pass effects of mirodenafil were approximately 21.4% and 54.3% of the oral dose, respectively. The low F value of mirodenafil in rats was mainly due to considerable hepatic and gastrointestinal first-pass effects in rats. The equilibrium plasma-to-blood cell partition ratios of mirodenafil were independent of the initial blood mirodenafil concentrations of 1-10 microg/ml; the mean values were 1.08-1.21. The plasma binding values of mirodenafil to rat plasma was 87.8%.

Topics: Animals; Dose-Response Relationship, Drug; Male; Penile Erection; Phosphodiesterase 5 Inhibitors; Pyrimidinones; Rats; Rats, Sprague-Dawley; Sulfonamides; Tissue Distribution

It has been reported that mirodenafil is primarily metabolized via hepatic cytochrome P450 (CYP) 1A1/2, 2B1/2, 2D1 and 3A1/2 in rats. It has also been reported that the protein expression of hepatic CYP3A1 and intestinal CYP1A1 and 3A1/2 increases and that of hepatic CYP2D1 decreases in rats with acute renal failure induced by uranyl nitrate (U-ARF rats). Thus, the pharmacokinetics of mirodenafil were studied in control and U-ARF rats.. The pharmacokinetic parameters of mirodenafil and SK3541 (a metabolite of mirodenafil) were compared after the intravenous and oral administration of mirodenafil at a dose of 20 mg/kg to U-ARF and control rats.. After interavenous administration of mirodenafil to U-ARF rats, the total area under the concentration-time curve (AUC) of mirodenafil was significantly smaller (36.5% decrease) than controls, possibly due to the significantly faster non-renal clearance (66.1% increase; because of increase in the protein expression of hepatic CYP3A1) than controls. After the oral administration of mirodenafil to U-ARF rats, the AUC of mirodenafil was also significantly smaller (47.8% decrease) due to the increase in the protein expression of hepatic CYP3A1 and intestinal CYP1A1 and 3A1/2 compared with controls.. After both intravenous and oral administration of mirodenafil to U-ARF rats, the AUC(SK3541)/AUC(mirodenafil) ratios were comparable with that in controls and this could be due to further metabolism of SK3541 in rats.

Topics: Acute Kidney Injury; Administration, Oral; Animals; Aryl Hydrocarbon Hydroxylases; Cytochrome P-450 CYP1A1; Cytochrome P-450 CYP3A; Disease Models, Animal; Injections, Intravenous; Intestinal Mucosa; Liver; Male; Microsomes; Pyrimidinones; Rats; Rats, Sprague-Dawley; Sulfonamides; Uranyl Nitrate

Mirodenafil (SK3530) is a new potent and selective inhibitor of cGMP-specific phosphodiesterase type 5 (PDE5). Recent clinical trials have demonstrated that mirodenafil is an effective treatment for erectile dysfunction. Its mechanism of action is enhancement of nitric oxide (NO) induced cGMP formation resulting in significant relaxation of the corpus cavernosum (CC). The aim of this study was to investigate the oral efficacy of mirodenafil in an acute spinal cord-injured rabbit model. Mirodenafil or sildenafil citrate was given orally to male rabbits with a surgical transection of the spinal cord at the L2-L4 lumbar vertebra or ischemic-reperfusion spinal cord injury (SCI). Erections were evaluated in a time-course manner by measuring the length of the uncovered penile mucosa. In the transection SCI model, penile erections were induced at 0.3, 1 and 3 mg/kg of mirodenafil but sildenafil only showed an erectile response at 3 mg/kg. The effects of 1 and 3 mg/kg of mirodenafil were significantly increased by intravenous injection of sodium nitroprusside (SNP), a nitric oxide donor. In the ischemic-reperfusion injury model, 3 mg/kg of either mirodenafil or sildenafil produced a penile erection response. After injection of SNP, the lengths of immediate penile erections were significantly increased in the 1 and 3 mg/kg mirodenafil and 3 mg/kg sildenafil groups. The onset of erectile activity was faster with mirodenafil than with sildenafil citrate. These results demonstrate that mirodenafil may be useful for treating erectile dysfunction in patients with a spinal cord injury.

Topics: Administration, Oral; Animals; Erectile Dysfunction; Male; Mucous Membrane; Penile Erection; Phosphodiesterase 5 Inhibitors; Pyrimidinones; Rabbits; Spinal Cord Injuries; Sulfonamides

The purpose of this paper is to characterize the cytochrome P450 (CYP) enzymes involved in the metabolism of a new oral erectogenic, mirodenafil, to a major circulating active metabolite, N-dehydroxyethyl-mirodenafil, and to investigate the inhibitory potential of mirodenafil on seven CYP enzymes in human liver microsomes. CYP3A4 was identified as the major enzyme and CYP2C8 as a minor enzyme responsible for mirodenafil N-dealkylation based on correlation analysis, inhibition studies, and cDNA-expressed CYP enzyme activities. Plasma concentrations of mirodenafil and its N-dealkylated metabolite could therefore change with co-administration of known CYP3A4 inducers or inhibitors. Mirodenafil inhibited CYP3A4, CYP2C19 and CYP2D6 activities with IC50 values of 15.6, 38.2 and 77.0 microM, respectively, in human liver microsomes. However, it is very unlikely that mirodenafil will significantly alter the clearance of other compounds metabolized by CYPs 1A2, 2A6, 2C8, 2C9, 2C19, 2D6 and 3A4 because the maximum plasma concentration of mirodenafil is 0.55 microM after oral dosing of mirodenafil (100 mg) in male volunteers.

Topics: Cytochrome P-450 Enzyme Inhibitors; Cytochrome P-450 Enzyme System; Dealkylation; Dose-Response Relationship, Drug; Enzyme Inhibitors; Erectile Dysfunction; Humans; Kinetics; Male; Microsomes, Liver; Pyrimidinones; Substrate Specificity; Sulfonamides