A Trial for Prevention of Recurrent Ischemic Priapism in Men With Sickle Cell Disease: A Pilot Study

Prior treatment

• Previously known pulmonary hypertension based on TRJV greater than 3.0 m/sec
• Contraindications to tadalafil (arrhythmia, severe liver disease, concurrent use of nitrates, etc.) or hydroxyurea (leg ulcer, hypersensitivity, etc.).
• Patients who have penile prosthetic implants or shunts or any other surgical procedure on the penis
• Patients who have taken drugs/medications that may induce priapism over the 14 weeks before trial:
• Medications injected directly into the penis to treat erectile dysfunction, such as alprostadil, papaverine, phentolamine, and others
• Alcohol, marijuana, cocaine and other illicit drug abuse can cause priapism

Other illness

• Medications used to treat anxiety or psychotic disorders, such as hydroxyzine, risperidone, olanzapine, lithium, clozapine, chlorpromazine, and thioridazine
• Medications used to treat attention-deficit/hyperactivity disorder (ADHD), such as atomoxetine (Strattera)

Lab values

• eGFR \<50ml/min
• Liver cirrhosis based on clinical history, laboratory data or both

Other

• Individuals already enrolled in another clinical trial
• Antidepressants, such as fluoxetine, bupropion, and sertraline
• Alpha blockers including prazosin, terazosin, doxazosin, and tamsulosin
• Blood thinners, such as warfarin and heparin
• Hormones such as testosterone or gonadotropin-releasing hormone
• Not able to understand or comply with study instructions and requirements

• Men with confirmed diagnosis of HbSS or Hb beta zero thalassemia
• Ages between 18 to 40 years
• Eligible study participants must receive care in an SCD clinic at AKTH and MMSH at the time of the recruitment
• Participants must commit to long-term follow-up and taking the trial medications
• At least 3 episodes of priapism, each lasting for no less than an hour in the past 6 months.
• Adequate renal and hepatic function (baseline liver enzymes and synthetic activities should be no more than four-fold above the reference ranges for Aminu Kano Teaching Hospital (AKTH). These are the ranges obtained in AKTH: Alkaline phosphatase: 42-110 U/L, Alanine transaminase: 4-34 U/L, Aspartate transaminase: 7-45 U/L, Albumin: 32-52 g/L, and Globulin: 32-43 g/L.