Low Intensity Extracorporeal Shock Wave Treatment for Erectile Dysfunction: Standardisation of Treatment Protocol

This is a randomized, 4 parallel arms, clinical trial with an 18-month recruitment period. All patients will be PDE5I users/responders. After 1 month wash-out period, ED patients will be screened, in order to randomize 96 men with vasculogenic ED, an International Index of Erectile Function ED (IIEF-ED) domain score between 6-25 and abnormal penile triplex-based hemodynamic parameters (peak flow velocity <35cm/sec) in the last 6 months. Additionally, they will be asked to complete the SEP diaries. Patients will be randomized to receive shockwave treatments (12 sessions for all subjects), either twice a week (total of 6 weeks) or three times a week (total of 4 weeks) at energy level 4 or 7, without treatment interval.

Study visits and duration

Visit 1 (day 0): the basic work-up will take place, including medical and sexual history, as well as necessary lab tests, if needed. One month wash-out period will follow. During this period, all subjects will be asked to avoid any drug related to ED (PDE5i) and have at least 2-4 attempts for intercourse. Furthermore, patients will undergo triplex ultrasonography, unless they have already done so in the last 6 months.Also penile dimensions in both flaccid and erect state will be measured.

Visit 2 (day 28 + 3 days): all patients will complete the IIEF-ED domain and will be randomized to one of the four parallel study groups, using an online program. Groups A and C will receive treatment twice per week, at energy level 4 and 7 respectively. Groups B and D will receive treatment three times per week, at energy level 4 and 7 respectively. PDE5i use is prohibited throughout the study.

Treatment Visits: There will be 12 active treatment visits for all 4 Groups. Patients will receive LI-ESWT, according to the study protocol. Interval between 2 treatments will be 3+1 days for Groups A and C (twice/week) whereas 1+1 day for Groups B and D (three times/week). At visit 6 and 12 a penile ultrasonography will be conducted in order to check for potential adverse events related to the treatment.

Follow-up visits 1 - 3 (4, 12 ,24 and 48 weeks post treatment): Patients will complete the IIEF-ED questionnaire and return the completed SEP diaries for the last 4 weeks prior to every visit. Visit data will also be recorded (protocol compliance, adverse events). At Week 12, triplex will be performed by the standard protocol. For Week 4 there is a + 3 days visit window, whereas for weeks 12, 24 and 48 there is a + 2 weeks visit window.

Inclusion criteria

• Consent to participate
• Age >18
• Presence of vasculogenic erectile dysfunction for at least 6 months
• Positive response to PDE5i
• IIEF-ED score > 6 and IIEF score < 26 after wash out of PDE5i
• Abnormal penile triplex-based hemodynamic parameters (peak flow velocity <35cm/sec)
• Stable heterosexual relationship for more than 3 months
• Sexually active and agree to suspend all ED therapy for the duration of study

Exclusion criteria

• Any cause of ED other than vascular related
• Previous radiation therapy to pelvis
• History of radical prostatectomy
• Clinically significant chronic haematological disease
• Cardiovascular conditions that prevent sexual activity
• Peyronie's Disease or penile curvature
• History of heart attack, stroke or any life- threatening arrhythmia within the prior 6 month
• Anti-androgens oral or injectables androgens
• Untreated Hypogonadism as demonstrated by abnormal testosterone levels
• Malignancy within the past 5 years
• Any unstable medical, psychiatric condition or spinal cord injury
• Anatomical or neurological abnormalities in the treatment area
• Use of any treatment for ED within 7 days of screening ( oral medications, vacuum devices, constrictive devices, injections or urethral suppositories)
• Known allergy to ultrasound gel