Physician-rated patient preference and patient- and partner-rated preference for tadalafil or sildenafil citrate: results from the Canadian 'Treatment of Erectile Dysfunction' observational study

OBJECTIVE To determine physician-based ratings of patient preference, patient preference, partner preference and physician-based assessment of the reasons for patient preference for tadalafil or sildenafil citrate (sildenafil) as a treatment for erectile dysfunction (ED) in routine clinical practice. Phosphodiesterase type 5 inhibitors (PDE5i) are effective and well-tolerated therapies for ED, but patient and partner preferences for these treatments might be determined by many factors, both medical and nonmedical. PATIENTS AND METHODS The Treatment of ED (TED) observational trial was a multicentre study conducted in Canada to determine patient and partner preferences for the PDE5i taclalafil or sildenafil in routine clinical practice. Patients who planned to change treatment from tadalafil or sildenafil to the alternative drug were invited to participate in the study. The study duration was 4-12 weeks. At visit 1 (baseline), patient background information was collected. At visit 2, physicians answered the physician-rated Patient-treatment preference questionnaire, patients answered the treatment preference question (TPQ) and the global assessment question (GAQ), and partners answered the partner TPQ. RESULTS The TED study was conducted at 266 sites across Canada and involved 2425 patients who used the allowed study medications, and 295 sexual partners who attended clinic visits. More than 98% of patients completed the study. Responses to the preference questionnaires showed that physician-rated patient preference, patient preference, and partner preference had a similar pattern preference, with a significantly higher proportion preferring taclalafil over sildenafil regardless of the change in treatment (i.e. sildenafil to tadalafil or tadalafil to sildenafil). Responses to the GAQ showed that nearly 90% of the patients who took either PDE5i said that the treatment had improved erections. CONCLUSIONS TED is the first study to assess physician-based ratings of patient preference, patient preference, and partner preference for tadalafil or sildenafil in a routine clinical practice settings. Most participants preferred tadalafil over sildenafil. Understanding the underlying reasons influencing the preference might improve patient compliance and satisfaction with treatment.