Commentary on – “Comparison of the efficacy and safety of once-daily dosing and on-demand use of udenafil for type 2 diabetic patients with erectile dysfunction”

Dear Editor,

We read with interest of the article written by Park et al.1 They performed a randomized controlled trial to compare efficacy and safety between 50 mg once-daily and 200 mg on-demand dosing use of udenafil for the treatment of type 2 diabetic patients with erectile dysfunction (ED). Their findings indicated that the most common drug-related adverse events (AEs) were flushing (8.9% vs 2.5%) and headache (3.8% vs 1.3%) between the on-demand group and the daily-dosed group. Although the authors believed that the udenafil was well-tolerated in both groups, unfortunately, they failed report the total incidence of AEs to assess the safety of the two groups.

We agree with their view that both the 50 mg once-daily group and 200 mg on-demand group of udenafil for type 2 diabetic patients with ED were well tolerated. Furthermore, Moon du et al.2 performed a randomized, double-blind controlled trial to assess the safety of udenafil for treatment of ED in patients with diabetes mellitus. They found that the total rate of AEs related to the 200 mg udenafil on-demand was 22.4%, and the most frequent drug-related AEs were flushing and headache with incidences of 10% and 5%, respectively. In addition, other major AEs were nausea and conjunctival hyperemia. Paick et al.3 performed a multicenter, double-blind and parallel-group trial to evaluate the efficacy and safety of 200 mg udenafil therapy in patients with ED. However, they found that the higher of incidence of treatment-related AEs was 37.5%, and flushing rate was 23.2%, nasal congestion and ocular hyperemia rate were 7.1% independently, headache rate was 8.9%, chest discomfort rate 5.4%, withdrawal due to AEs was 3.6%. Zhao et al.4 performed a multicenter, randomized, double-blind, controlled trial to evaluate the efficacy and safety of once-daily dosing of udenafil in the treatment of ED. They found the incidence of AEs using udenafil 50 mg once-daily for ED patients was 10%.

There are some differences in incidence rates of AEs among the studies.2,3,4,5,6 Thus, we believe that the AEs rate may be an important parameter to assess the drug safety. Meanwhile, we consider it is better to report the rate and classify of AEs contributed to objectively and fairly evaluate the safety between 50 mg once-daily and 200 mg on-demand dosing use of udenafil for the treatment of type 2 diabetic patients with ED, although most studies indicated AEs of udenafil for ED were safe.5,6

CONFLICTS OF INTEREST

There are no conflicts of interest to declare.