DAFA06: The Management of Erectile Dysfunction With Placebo Only

Sponsor

Rio de Janeiro State University (Other)

Overall Status

Completed

CT.gov ID

NCT00882934

Collaborator

(none)

123

Enrollment

Arms

Duration (Months)

Study Details

Study Description

Brief Summary

Placebo-controlled randomized clinical trials (RCT) are the gold standard to provide applicable evidence for clinical practice. A vast number of RCTs for treatment of several disorders has shown a mean placebo effect of 30%. Erectile dysfunction (ED) is a high prevalent disease and its first-line therapy is oral phosphodiesterase type-5 inhibitor (iPDE5) (i.e., sildenafil, vardenafil and tadalafil). Although the placebo effect in iPDE5 RCT occurred at a rate as high as 50%, in the last decade, with the revolutionary discovery of effective pharmacotherapy for ED, oral iPDE5 has become one of the most common prescribed drugs for men. The objective of this study is to evaluate the influence of patients' awareness on the composition of the therapeutic drug in the outcomes of the oral treatment for ED.

Condition or Disease	Intervention/Treatment	Phase
Impotence Erectile Dysfunction	Other: Induction to efficient treatment Other: Doubt to the efficacy of treatment Other: Induction to ineffective treatment	N/A

Study Design

Study Type:

Interventional

Actual Enrollment :

123 participants

Allocation:

Randomized

Intervention Model:

Parallel Assignment

Masking:

Single (Investigator)

Primary Purpose:

Treatment

Official Title:

A Single-Blind, Controlled, Randomized, Parallel-Group Study of the Efficacy of Patients' Awareness on the Composition of the Experimental Drug in the Treatment of Erectile Dysfunction.

Study Start Date :

Oct 1, 2006

Actual Primary Completion Date :

Oct 1, 2007

Actual Study Completion Date :

Jan 1, 2008

Arms and Interventions

Arm	Intervention/Treatment
Experimental: A1 Arm 1 received an informative letter explaining that they were allocated to receive a substance for Erectile Dysfunction treatment.	Other: Induction to efficient treatment Informative letters.
Placebo Comparator: A2 Arm 2 (A2) was written informed that they could or could not receive an active drug for ED treatment.	Other: Doubt to the efficacy of treatment Informative letters.
Experimental: A3 Arm 3 (A3) was properly written informed to be using no effective drug for ED treatment.	Other: Induction to ineffective treatment Informative letters

Arm

Intervention/Treatment

Experimental: A1

Arm 1 received an informative letter explaining that they were allocated to receive a substance for Erectile Dysfunction treatment.

Other: Induction to efficient treatment

Informative letters.

Placebo Comparator: A2

Arm 2 (A2) was written informed that they could or could not receive an active drug for ED treatment.

Other: Doubt to the efficacy of treatment

Informative letters.

Experimental: A3

Arm 3 (A3) was properly written informed to be using no effective drug for ED treatment.

Other: Induction to ineffective treatment

Informative letters

Outcome Measures

Primary Outcome Measures

IIEF erectile function domain score [4 AND 8 Weeks]
Quality of Erection Questionnaire (QEQ) [4 and 8 weeks]

Secondary Outcome Measures

IIEF orgasmic function, sexual desire, intercourse satisfaction and overall satisfaction domain scores [4 and 8 weeks]
SEAR questionnaire [4 and 8 weeks]
EDITS questionnaire [4 and 8 weeks]
GEAQ questionnaire [4 and 8 weeks]

Eligibility Criteria

Criteria

Ages Eligible for Study:

18 Years and Older

Sexes Eligible for Study:

Male

Accepts Healthy Volunteers:

Inclusion Criteria:

18 years of age or older
Complaint of ED for at least 6 months prior the start of the study, according to medical history and to the questionnaires IIEF, SEAR and QEQ.
A stable heterosexual relationship.
To be in good health prior the participation in the study, with no important clinical abnormalities, determined by: clinical history, physical examination, blood chemistry and hematology, urinalysis (If the standard values of the laboratory for these tests are not evidenced, subjects can be included if the researcher consider the changes as not clinically significant).

Exclusion Criteria:

History of significant cardiovascular, pulmonary, gastrointestinal, hematological, neurological (including epilepsy), locomotor, immunologic, ophthalmic, metabolic, endocrine, thromboembolic, rheumatologic, cancer, kidney or liver disease.
Diagnosis of psychiatric conditions, e.g. depression, anxiety, dysthymia, mania, panic, agoraphobia, social phobia, suicidal ideation, obsessive-compulsive disorder, post-traumatic stress, psychotic disorders, schizophrenia, alcoholism, dependence on psycho-active substances.
History of HIV, hepatitis B or hepatitis C.
Hyperprolactinemia or untreated hypothyroidism.
Any condition, which, in the opinion of the investigator, may interfere with the participation of the subject in the study (e.g. difficulty to meet the requirements of the study, attend the consultations, answer the questionnaires).
Report of significant clinical problems by the subject's partner, such as decreased sexual interest, pain during relations or other forms of sexual dysfunction that interfere in the relationship with the sexual partner.
Patient or partner willing to undergo a surgical procedure during the study period, which may interfere in the results.
Peyronie's disease, which may lead to impossibility to penetrate or cause pain during the sexual intercourse.
Use of nitrates.
Illiterate patient.