Overview of Trials

Two studies were identified and were judged to be eligible to address the present question. Both trials were randomized5,77 comparing the efficacy of combined treatment of testosterone (gel or patch) plus sildenafil to that of sildenafil alone in ED patients with low testosterone levels who failed to respond (score of 2–3 on IIEF–Q3/Q4) to prior treatment with sildenafil.

Gel testosterone plus sildenafil versus sildenafil. In this double-blind trial5 75 hypogonadal men (mean age: 58 years; total testosterone <400 ng/dL) with ED were randomized to 1 percent gel testosterone plus 100 mg sildenafil versus 100 mg sildenafil for 12 weeks. At the end of the study, the proportions of men with scores of 4-5 on IIEF–Q3/Q4 was statistically nonsignificantly greater in the combination therapy group than in the sildenafil only group (51.4 versus 39.4 percent; RR = 1.30, 95 percent CI 0.77–2.21). Men who received gel testosterone plus sildenafil also had greater mean change from baseline in the IIEF “EF” domain score at week 4 (4.4 versus 2.1, 95 percent CI: 0.3–4.7). One patient withdrew from the combination treatment arm due to an adverse event.

Testosterone patch plus sildenafil versus sildenafil. In this open label trial,77 20 hypogonadal men (mean age:56 years; total testosterone:10-13 nmol/L) with ED were randomized to receive either 5 mg patch testosterone plus 100 mg sildenafil or 100 mg sildenafil plus placebo patch. After one month of treatment, patients in the patch testosterone plus sildenafil group had either numerically or statistically significant improvements for the following outcomes:

• “EF domain” score (21.8 +/- 2.1 versus 14.2 +/- 0.7, WMD = 7.60, 95 percent CI: 6.23–8.97),
• number of sexual intercourses (2.8 +/- 0.9 versus 1.5 +/- 0.5, WMD = 1.30, 95 percent CI: 0.66–1.94),
• intercourse satisfaction (12.1 +/- 1.6 versus 7.7 +/- 1.2, WMD = 4.40, 95 percent CI: 3.16–5.64),
• reported improved erections (80 versus 10 percent, RR = 8.00, 95 percent CI: 1.21–52.69).