Table 1.

Efficacy of tadalafil once daily from randomized controlled trials

Study	Design	Subjects	Treatment	End points	Findings
Porst et al42	RDBPCSs	293 men with ≥3 month history of ED	Tadalafil 5 mg or 10 mg daily for 12 wk	IIEF-EF domain score, SEP2, SEP3	Tadalafil significantly improved EF relative to placebo regardless of baseline ED severity
Rajfer et al47	RDBPCSs	287 men with ≥3 month history of ED	Tadalafil 2.5 mg or 5 mg daily for 24 wk	IIEF-EF domain score, SEP2, SEP3	Tadalafil significantly improved EF relative to placebo regardless of baseline ED severity, with the 5 mg group experiencing numerically greater improvements than the 2.5 mg group
Hatzichristou et al49	RDBPCSs	298 men with ≥3 month history of diabetes (type 1 or type 2) and ED	Tadalafil 2.5 mg or 5 mg daily for 12 wk	IIEF-EF domain score, SEP2, SEP3	Significant improvements in erectile function seen across all ED and diabetes subgroups treated with tadalafil
Porst et al48	1- and 2-y extensions of 2 RDBPCSs	234 men with ED who completed a 12-wk treatment period and 238 men with ED who completed a 24-wk treatment period, all enrolled in open-label extensions	Tadalafil 5 mg or 10 mg daily for 12 wk, and tadalafil 2.5 mg or 5 mg daily for 24 wk	Safety: adverse event incidence, ECGs, clinical laboratory measures; efficacy: IIEF-EF, -IS, -OS, GAQ1, GAQ2	No treatment-related serious adverse events or meaningful changes in clinical measures, normal EF attained by >50% of patients from both arms
Rubio-Aurioles et al52	RDBPCSs	342 men with ≥3 month history of ED and their female partners	Tadalafil 5 mg daily for 12 wk	IIEF-EF domain score, SEP2, SEP3, SQoL domain	Tadalafil-treated couples more likely to report sexual quality of life comparable to what was experienced before ED onset
Seftel et al53	RDBPCSs	264 men with ≥3 month history of ED and their partners who met criteria for inclusion in this follow-up arm of this study	Tadalafil 5 mg daily for 12 wk	IIEF-EF domain score, SEP2, SEP3, SQoL domain	Men treated with tadalafil had significant changes in EF, confidence, self-esteem, overall relationship, and partner’s satisfaction
Porst et al50	Post hoc analysis of a phase 2–3 RDBPCS	581 men with ED from study focused on BPH-LUTS	Tadalafil 2.5 mg, 5 mg, 10 mg, or 20 mg daily for 12 wk	IIEF-EF domain score, IPSS, peak urinary flow rate, and postvoid residual volume	Tadalafil significantly improved IIEF and IPSS scores independent of all other factors
Shabsigh et al35	Post hoc analysis of 2 RDBPCSs	450 men with ≥3 month history of ED	Tadalafil 2.5 mg or 5 mg daily for 12 wk	Reliability (no. of “yes” responses to SEP3 after initial attempt)	5 mg group had increased rates of reliability, intercourse success, and satisfaction

Abbreviations: ECG, electrocardiogram; ED, erectile dysfunction; EF, erectile function domain; GAQ1, Global Assessment Question 1; GAQ2, Global Assessment Question 2; IIE F, International Index of Erectile Function; IIE F-EF, International Index of Erectile Function-erectile function domain; IIE F-IS, International Index of Erectile Function-Intercourse satisfaction domain; IIEF-OS, International Index of Erectile Function-Overall satisfaction domain; IPSS, International Prostate Symptoms Score; RDBPCSs, randomized, double-blind, placebo-controlled studies; SEP, sexual encounter profile; SQoL, Sexual Quality of Life Domain of the Sexual Life Quality Questionnaire.