Table 2. Studies evaluating PDE-5-I administration for ED in Asian men31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44.
| Study | Drug | Study design | Patients | Outcome measures | Efficacy | Adverse event |
|---|---|---|---|---|---|---|
| Tan et al.31 | Sildenafil versus placebo (50 mg increased to 100 mg or decreased to 25 mg) for 12 weeks | Multinational, multi-institutional randomized controlled trial | 254 men;aged 26–78 years;ED duration >6 months | IIEF, patients' event logs of sexual activity, and a global efficacy question | Higher EF with sildenafil than with placebo, IIEF Q3 (4.22 versus 2.59) and Q4 (4.15 versus 2.41) (P<0.0001), | 22.8% of sildenafil versus 10.2% of placebo; flushing, dizziness and headache |
| significantly improved IIEF-EF and GEAQ in sildenafil group (P<0.0001) | ||||||
| Kongkanand et al.32 | Sildenafil versus placebo (50 mg increased to 100 mg or decreased to 25 mg) for 12 weeks | Multi-institutional randomized controlled trial in Thailand | 125 men;aged 26–77 years;ED duration >6 months | IIEF, patients' event logs of sexual activity, and a global efficacy question | Higher EF with sildenafil than with placebo, successful attempts at sexual intercourse (66.16% versus 33.05%) | 30.2% of sildenafil versus 11.3% of placebo; flushing, dizziness and headache |
| Chen et al.33 | Sildenafil versus placebo (50 mg increased to 100 mg or decreased to 25 mg) for 12 weeks | Multi-institutional randomized controlled trial in Taiwan | 236 men;aged 26–80 years;ED duration >6 months | IIEF, patients' event logs of sexual activity, and a global efficacy question | Higher EF with sildenafil than with placebo, IIEF Q3 (4.17 versus 2.98) and Q4 (4.14 versus 2.88) (P<0.0001), significantly improved IIEF-EF and GEAQ in sildenafil group (P<0.0001) | 43.7% of sildenafil versus 18.8% of placebo; flushing, dizziness and headache |
| Choi et al.34 | Sildenafil versus placebo (50 mg increased to 100 mg or decreased to 25 mg) for 8 weeks | Multi-institutional randomized controlled trial in Korea | 133 men;aged 28–78 years;ED duration >6 months | IIEF, patients' event logs of sexual activity, and a global efficacy question | Higher EF with sildenafil than with placebo, IIEF Q3 (4.19 versus 2.67) and Q4 (3.74 versus 2.07) (P<0.0001), significantly improved IIEF-EF and GEAQ in sildenafil group (P<0.0001) | 56.1% of sildenafil versus 20.9% of placebo; flushing, headache and abnormalities in colour vision |
| Tan et al.35 | Vardenafil (10 mg) versus placebo for 12 weeks | Multinational, multi-institutional randomized controlled trial | 358 men;aged ≥20 years;ED duration >6 months | IIEF-EF domain score, success rate of vaginal penetration (SEP2), penile rigidity (SEP3), GAQ | Increased IIEF-EF scores in vardenafil compared with placebo (22.4 versus 14.3, P<0.001), improved SEP2 (82.2 versus 43.6, P<0.001), SEP3 (66.1 versus 24.0, P<0.001), positive GAQ responses (81.8% versus 24.3%) | 25.4% of the vardenafil group, the majority mild and transient headache, flushing, nasal congestion and dizziness |
| Chen et al.36 | Vardenafil (10 mg) versus placebo for 12 weeks | Multinational, multi-institutional randomized controlled trial | 306 men;aged ≥20 years;ED duration >6 months | IIEF-EF domain score, success rate of vaginal penetration (SEP2), penile rigidity (SEP3), GAQ | Greater increase in IIEF-EF score in vardenafil group compared with placebo (24.2 versus 15.9), higher SEP2 (88% versus 58%), higher SEP3 (69% versus 23%), higher positive GAQ responses (85% versus 33%) | 54.2% of vardenafil versus 43.0% of placebo; mild intensity flushing, rhinitis and headache |
| Yip et al.37 | Tadalafil (20 mg) versus placebo for 12 weeks | Multinational, multi-institutional randomized controlled trial | 242 men;aged >18 years;ED duration >3 months | IIEF,SEP diary,GAQ | Significantly improved EF in tadalafil compared with placebo (P<0.001), greater SEP3 (70.9% versus 33.5%), greater GAQ (86.2% versus 30.1%) | Headache (11.3%), back pain (7.5%), dizziness (3.8%) and dyspepsia (3.1%) |
| Guo et al.38 | Tadalafil (10 or 20 mg) versus placebo for 12 weeks | Multinational, multi-institutional randomized controlled trial | 367 men;aged >18 years;(>21 in Singapore)ED duration >3 month | IIEF,SEP diary,GAQ | Tadalafil 10 and 20 mg improve IIEF (8.1 and 8.7, versus placebo 2.4, P<0.001), SEP3 (62% and 70%, placebo 32%, P<0.001), GAQ (81% and 86% versus 44%, P<0.001) | Headache, back pain, dyspepsia and dizziness |
| Chen et al.39 | Tadalafil (10 or 20 mg) versus placebo for 12 weeks | Multi-institutional randomized controlled trial in Taiwan | 196 men;aged >21 years;ED duration >3 months | IIEF,SEP diary,GAQ | Tadalafil improved EF compared with placebo (P<0.005), SEP Q3: 70.0%, 10 mg; 78.0%, 20 mg versus 42.8% placebo, GAQ: 92.3% and 84.6% versus 54.5% placebo | Back pain, dyspepsia and myalgia |
| Guo et al.40 | Tadalafil (10 or 20 mg) versus placebo for 12 weeks | Integrated analysis of five double-blind, placebo-controlled trials | 1046 men;aged >18 years;ED duration >3 months | IIEF,SEP diary,GAQ | Tadalafil 10 or 20 mg improved IIEF-EF (P<0.001), better SEP Q3 (64.1%, 70.5% versus placebo 33.4%, P<0.001), improved GAQ (85.5%, 85.4% versus placebo 43.5%, P<0.001) | 1.3% of tadalafil versus 1.1% of placebo;headache and back pain |
| Paick et al.41 | Udenafil (100 or 200 mg) versus placebo for 12 weeks | Multi-institutional randomized controlled trial in Korea | 167 men;aged 19–70 years;ED duration >6 months | IIEF, SEP diary, GAQ | Significantly improved IIEF-EF, SEP Q2 and SEP Q3 (P<0.0001), GAQ (placebo, 25.9% udenafil 100 mg, 81.5% udenafil 200 mg, 88.5%, P<0.0001) | Flushing, headache and nasal congestion |
| Park et al.42 | Udenafil (100 mg) versus placebo for 4 weeks | Multi-institutional randomized controlled trial in Korea | 103 men;aged 19–70 years;ED duration >6 months | IIEF-EF domain score,SEP2, SEP3 | Enhanced SEP Q3 (placebo, 28.3% versus udenafil, 54.7% P<0.0001), significant change from base line in IIEF-EF (placebo, 0.58; udenafil, 4.40; P<0.0001) | 4% of placebo, 11.3% of udenafil;flushing, headache and toothache |
| Paick et al.43 | Mirodenafil (SK3530; 50, 100 or 150 mg) versus placebo for 8 weeks | Multi-institutional randomized controlled trial in Korea | 119 men;aged 19–70 years;ED duration >6 months | IIEF, SEP diary, GAQ | All primary and secondary efficacy end points significantly improved (P<0.05) 42.3% achieved normal erectile function after treatment | Flushing, headache, dizziness and eye redness (10.9%, 7.6%, 2.5% and 2.5%, respectively) |
| Paick et al.44 | Mirodenafil (50 or 100 mg) versus placebo for 12 weeks | Multi-institutional randomized controlled trial in Korea | 223 men;aged 19–70 years;ED duration >6 months | IIEF, SEP diary, GAQ, LSC | Mirodenafil 50 and 100 mg, greater increase in IIEF Q3, Q4 (P<0.0001), improved IIEF-EF, SEP2, SEP3, GAQ and LSC | Mild intensity flushing, headache, nausea and eye redness |
Abbreviations: ED, erectile dysfunction; EF, erectile function; IIEF, International Index of Erectile Function; GAQ, global assessment question; GEAP, global efficacy assessment question; LSC, life satisfaction checklist; PDE-5, phosphodiesterase-5; SEP, sexual encounter profile.