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Trial registered on ANZCTR

Registration number
Ethics application status
Date submitted
Date registered
Date last updated
Type of registration
Retrospectively registered

Titles & IDs
Public title
Do patients’ baseline characteristics with erectile dysfunction, predict phosphodiesterase type 5 (PDE5) inhibitors’ efficacy and patients’ preference? A comparative, randomized, open-label, crossover study.
Scientific title
To identify the parameters of a patient with specific social status and unique medical history, which can influence the reply to the phosphodiesterase type 5 (PDE 5) inhibitors due to erectile dysfunction.
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Erectile Dysfunction 252046 0
Condition category
Condition code
Other 252233 252233 0 0
Conditions of unknown or disputed aetiology (such as chronic fatigue syndrome/myalgic encephalomyelitis)

Study type
Description of intervention(s) / exposure
The patients were treated with the three known phosphodiesterase type 5 (PDE 5) inhibitors (sildenafil 100mg, vardenafil 20mg and tadalafil 20mg) which were administered with incidental sequence. A week wash out period was followed after each of the three treatment period.All of them completed the International Index of Erectile Function 15 (IIEF-15) questionnaire following by a detailed medical and psychological history. Baseline variables examined were age, body mass index, alcohol consumption, smoking status, physical activity, Erectile dysfunction (ED) aetiology/duration, comorbidities in medical history, medication intake, psychological status and baseline scores for the IIEF domains. The maximum dose was used for at least 4 attempts for intercourse with each one of them (4 pills from each drug) during a 4-weeks period. The attempt for intercourse must be start at least 30 minutes after the oraly intake of the medication (single dose) and not earlier. If the patient wanted to try second intercourse within 24 hours, he would have tried with the same pill. He might take second one only after at least 24 hours. No other instructions were given (about food intake or drink consumption). In every follow up visit, the Sexual encounter Profile (SEP) diary were selected and the IIEF questionnaire was completed. The study for statistically reasons divided in four arms. The first arm included the first visit of the patient to the doctor (before medication). The second arm included the results after sildenafil 100mg intake. The third and the fourth after vardenafil 20mg and tadalafil 20mg respectively.
Intervention code [1] 241441 0
Treatment: Drugs
Comparator / control treatment
Post-baseline variables examined were differences in International Index of Erectile Function (IIEF) domains, Sexual Encounter Profile (SEP) scores and the presence of side-effects of the three phosphodiesterase type 5 (PDE 5) inhibitors. We compare the patients' answer to each one PDE 5 inhibitor with the other and the baseline status (sildenafil vs vardenafil, sildenafil vs tadalafil, vardenafil vs tadalafil). Which baseline characteristics can influence the efficacy, tolerability and patient’s satisfaction?
Control group

Primary outcome [1] 253110 0
Participants' International Index of Erectile Function (IIEF) scores were estimated to identify the degree of erectile function, the orgasm, the satisfaction of the intercourse, the ejaculation and the general satisfaction.
Timepoint [1] 253110 0
Baseline and 4, 9, 14 weeks following randomisation
Secondary outcome [1] 257981 0
Patient drug preference as assessed by questionnaire and interview
Timepoint [1] 257981 0
14 weeks following randomisation

Key inclusion criteria
Erectile dysfunction for at least 6 months
Minimum age
No limit
Maximum age
No limit
Can healthy volunteers participate?
Key exclusion criteria
1) Myocardial infarction until 6 months ago
2) Nitrite drug administration
3) Present urogenital infection
4) PDE 5 inhibitor intake at least 3 months before the study begins
5) Peyronie disease or other anatomic disorders of the penis
6) The existence of a serious neurological problem such as multiple sclerosis or stroke or spinal cord injury
7) The existence of erectile dysfunction <6 months

Study design
Purpose of the study
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?

Intervention assignment
Other design features
Phase 4
Type of endpoint(s)
Statistical methods / analysis

Recruitment status
Date of first participant enrolment
Date of last participant enrolment
Date of last data collection
Sample size
Accrual to date
Recruitment outside Australia
Country [1] 2288 0
State/province [1] 2288 0

Funding & Sponsors
Funding source category [1] 243916 0
Self funded/Unfunded
Name [1] 243916 0
Toutziaris Chrysovalantis
Address [1] 243916 0
Embedokleous 95
54351 Thessaloniki
Country [1] 243916 0
Primary sponsor type
Toutziaris Chrysovalantis
Embedokleous 95
54351 Thessaloniki
Secondary sponsor category [1] 251268 0
Name [1] 251268 0
Address [1] 251268 0
Country [1] 251268 0

Ethics approval
Ethics application status
Ethics committee name [1] 244030 0
Bioethical committee of Aristotle University of Thessaloniki (auth)
Ethics committee address [1] 244030 0
Ethics committee country [1] 244030 0
Date submitted for ethics approval [1] 244030 0
Approval date [1] 244030 0
Ethics approval number [1] 244030 0

Brief summary
To compare the efficacy and the side effects of the three known phosphodiesterase type 5 inhibitors (PDE 5i)in patients with erectile dysfuction. Are there specific baseline characteristics that can influence the patients' tolerability and patients' reply to each PDE 5 inhibitor.
Trial website
Trial related presentations / publications
Public notes

Principal investigator
Name 30407 0
Address 30407 0
Country 30407 0
Phone 30407 0
Fax 30407 0
Email 30407 0
Contact person for public queries
Name 13654 0
Toutziaris Chrysovalantis
Address 13654 0
Embedokleous 95
54351 Thessaloniki
Country 13654 0
Phone 13654 0
Fax 13654 0
Email 13654 0
Contact person for scientific queries
Name 4582 0
Toutziaris Chrysovalantis
Address 4582 0
Embedokleous 95
54351 Thessaloniki
Country 4582 0
Phone 4582 0
Fax 4582 0
Email 4582 0

No information has been provided regarding IPD availability
Summary results
Have study results been published in a peer-reviewed journal?
Other publications
Have study results been made publicly available in another format?
Results – basic reporting
Results – plain English summary