Tadalafil Fares Better Than Tamsulosin for Men with BPH

Atlanta—Both tadalafil and tamsulosin significantly improved lower urinary tract symptoms/benign prostatic hypertrophy (LUTS/BPH). However, only tadalafil significantly improved secondary LUTS/BPH measures of quality of life, Patient and Clinician Global Impression of Improvement (PGI-I and CGI-I) scales, and treatment satisfaction.

These findings were presented during a poster session at the AUA meeting. The poster was titled Effects of Tadalafil or Tamsulosin on Lower Urinary Tract Symptoms Suggestive of Benign Prostatic Hyperplasia and on Erectile Dysfunction: Results from an International, Double-Blind, Placebo-Controlled Trial.

Improvements in LUTS/BPH with tadalafil 5 mg once daily have been demonstrated in several randomized, placebo-controlled studies regardless of erectile dysfunction (ED).

“Given that the alpha-blocker tamsulosin is often used as a first-line treatment for LUTS/BPH, assessing the efficacy of monotherapy with either tadalafil or tamsulosin in the same trial is of particular interest,” the researchers said.

The phase 3, randomized, double blind, parallel-design, placebo and active trial conducted at 44 centers worldwide assessed the effects of tadalafil or tamsulosin versus placebo on LUTS/BPH, and on ED in men who were sexually active. The primary comparison was between tadalafil and placebo; tamsulosin was included as an active control. The study was not powered for direct comparison between active treatments.

Primary efficacy outcome was change in total International Prostate Symptom Score (IPSS) at 12 weeks or last measurement. The study included 511 men ≥45 years of age who had moderate-to-severe LUTS/BPH with IPSS ≥13 and maximum flow rate (Q_MAX) 4 to 15 mL/s for >6 months. Patients were not allowed to use finasteride within 3 months, dutasteride therapy within 6 months, or any BPH therapy (including herbal preparations), overactive bladder therapy, or ED therapy within 4 weeks prior to the second visit.

Due to inclusion of a tamsulosin dosing arm, men were excluded for planned cataract surgery, history of symptomatic orthostatic hypotension, recurrent dizziness, vertigo, loss of consciousness, or syncope.

After a 4-week, placebo run-in period, patients were randomized to 12 weeks of placebo (n=172), tadalafil 5 mg (n=171), or tamsulosin 0.4 mg (n=168). The results showed that tadalafil (−2.1; 95% confidence interval [CI], −3.3 to −0.8; P=.001) and tamsulosin (−1.5; 95% CI, −2.8 to −0.2; P=.023) significantly improved total IPSS at 1 and 4 weeks, compared with placebo.

Both treatments also improved Benign Prostatic Hyperplasia (BPH) Impact Index (BII) at 4 and 12 weeks versus placebo (tadalafil, −0.8; 95% CI, −1.3 to −0.3; P=0.003; tamsulosin, −0.6; 95% CI, −1.1 to −0.1; P=.026). Q_MAX increased significantly at end point with both tadalafil (2.4 mL/s; P=.009) and tamsulosin (2.2 mL/s; P=.014), compared with placebo.

Tadalafil, but not tamsulosin, showed significant improvements versus placebo on the IPSS Quality of Life Index (−1.3 vs −1.0, respectively; P=.022), BPH Treatment Satisfaction Scale scores (22.2 vs 28.9, respectively; P=.005), PGI-I scale (125 vs 100, respectively; P=.005), and CGI-I scale (124 vs 100, respectively; P=.013). In sexually active men with ED, tadalafil significantly improved the International Index of Erectile Function–Erectile Function domain score at end point, compared with placebo (P<.001), whereas tamsulosin did not.

The incidence of treatment-emergent adverse events was higher in the tadalafil (23.4%) and tamsulosin (23.8%) groups, compared with placebo (20.3%). The most common adverse events were headache, nasopharygitis, back pain, dizziness, and dyspepsia.

This study was supported by Eli Lilly and Company.