Testosterone Gel Fails to Boost Viagra Response
Study found no added benefit for men with erectile dysfunction (Nov. 20)
Men with erectile dysfunction (ED) and low testosterone levels derive no extra benefit from adding testosterone to Viagra (sildenafil, Pfizer), a new study suggests.
The randomized, double-blind, parallel-group, placebo-controlled trial was led by researchers at the Boston University School of Medicine.
The study involved 140 men aged 40 to 70 years with scores of 25 or less for the erectile function domain (EFD) of the International Index of Erectile Function; total testosterone levels of less than 11.45 nmol/L (< 330 ng/dL); or free testosterone levels of less than 173.35 pmol/L (< 50 pg/mL).
After the sildenafil dose was optimized, the participants were randomly assigned to receive a daily transdermal gel that contained 10 grams of testosterone (n = 70) or placebo (n = 70) for 14 weeks. All of the participants were included in the primary analysis, although 10 in the testosterone group and 12 in the placebo group did not complete the study.
The two treatment groups had similar EFD scores at baseline. The administration of sildenafil alone was associated with a substantial increase in the EFD score (mean: 7.7), but after the patients were randomized to receive the testosterone gel, the change in the score did not differ significantly between the two groups (difference: 2.2; P = 0.150). The findings were similar for other domains of sexual function in younger men, more obese men, and men with lower baseline testosterone levels or an inadequate response to sildenafil alone.
The study appears in the November 20 issue of Annals of Internal Medicine.
Source: Annals of Internal Medicine; November 20, 2012.