Daily Tadalafil 5 mg Combined With On-Demand Sildenafil 100 mg for Treatment of Erectile Dysfunction in PDE-5I Non Responder Patients

Daily Tadalafil 5 mg Combined With On-Demand Sildenafil 100 mg for Treatment of Erectile Dysfunction in PDE-5I Non Responder Patients: A Multicenter Randomized, Double-Blind, Placebo-Controlled Trial

The goal of this clinical trial is to evaluate whether daily dosing with tadalafil 5 mg combined with on-demand sildenafil 100 mg can improve erectile function in men with erectile dysfunction (ED) who do not respond to PDE5 inhibitor alone.

The main questions it aims to answer are:

• Does the combination of daily tadalafil and on-demand sildenafil lead to a greater improvement in erectile function (measured by the IIEF-EF domain) compared with on-demand sildenafil alone?
• Is the combination therapy safe and well tolerated in this patient population?

Researchers will compare:

• Group A: Daily tadalafil 5 mg plus on-demand sildenafil 100 mg
• Group B: Daily placebo plus on-demand sildenafil 100 mg

to determine whether the combination regimen provides superior improvement in erectile function and patient satisfaction.

Participants will:

• Undergo baseline assessment including medical history, physical examination, and laboratory tests.
• Be randomly assigned to one of the two treatment groups.
• Take the assigned medications for 12 weeks.
• Complete follow-up evaluations at 4, 8, and 12 weeks, including:

International Index of Erectile Function (IIEF-15) questionnaire Erection Hardness Score (EHS) assessment Reporting of any adverse effects

Inclusion Criteria:

• Sexually active male.
• History of ED for ≥6 months.
• Erectile function domain of IIEF-15 score <17.
• Documented failure to respond to PDE-5I [definition of non-responder patients are patients with ED who don't respond to maximum dose of PDE-5I on ≥4 occasions in spite of accurate timing and good sexual stimulation].
• Stable sexual relationship ≥ 6 months.

Exclusion Criteria:

• Penile anatomical deformities or Peyronie's disease.
• Pelvic surgery or radiation.
• Active malignancy or severe systemic illness.
• Previous penile surgery of any kind, such as penile prosthesis, penile lengthening, penile cancer surgery, penile plication or grafting.
• Contraindication to PDE5i (High risk cardiac patients, patients on nitrates, hypotension).
• Using other treatments for ED e.g., Intra-cavernoasl prostaglandin injection therapy.