Sildenafil in Treating Erectile Dysfunction in Patients With Prostate Cancer

Study Overview
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Brief Summary
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RATIONALE: Sildenafil may be effective in helping patients who have undergone treatment for prostate cancer to have an erection for sexual activity and may improve sexual satisfaction and quality of life. PURPOSE: Randomized clinical trial to study the effectiveness of sildenafil in treating erectile dysfunction in patients who have undergone radiation therapy and hormone therapy for prostate cancer in clinical trial RTOG-9910.

Detailed Description
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OBJECTIVES: Compare the effect of sildenafil vs placebo on erectile dysfunction in patients with prostate cancer treated with radiotherapy and antiandrogens on RTOG-9910. Compare the overall sexual function and satisfaction of patients treated with these regimens. Compare sexual satisfaction of partners of patients treated with these regimens. Compare patient and partner marital adjustment after treatment with these regimens. Determine factors that may predict response to sildenafil, including age, pretreatment sexual function, tobacco use, and comorbidities in these patients. OUTLINE: This is a randomized, placebo-controlled, multicenter study. Patients are stratified according to prior use of sildenafil after treatment on RTOG-9910 and level of response (No vs yes [unsatisfactory] vs yes [satisfactory]), International Index of Erectile Function (IIEF) Question #1 score (0-1 vs 2-3), and RTOG-9910 treatment arm (I vs II). Patients are randomized to 1 of 2 treatment arms. Arm I: Patients receive oral sildenafil 1 hour prior to desired sexual intercourse. Arm II: Patients receive oral placebo 1 hour prior to desired sexual intercourse. Treatment on both arms continues for 12 weeks. Patients then cross over to treatment on the other arm for 12 weeks. Quality of life, including sexual function, marital adjustment, and partner's satisfaction, is assessed at baseline, at 12 and 25 weeks, and at 1 year. Patients are followed at 1 year. PROJECTED ACCRUAL: A total of 332 patients (166 per treatment arm) will be accrued for this study.

Official Title
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Treatment Of Erectile Dysfunction In Patients Treated On RTOG-9910 For Prostate Cancer: Impact On Patient And Partner Quality Of Life

Conditions
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Prostate Cancer, Psychosocial Effects of Cancer and Its Treatment, Radiation Toxicity, Sexual Dysfunction, Sexuality and Reproductive Issues

Intervention / Treatment
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* Drug: sildenafil citrate
* Other: Placebo


Participation Criteria
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Eligibility Criteria
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DISEASE CHARACTERISTICS: Prior treatment on RTOG-9910 for intermediate relapse-risk stage II or III prostate cancer as determined by any of the following combinations of factors: T1b-4, Gleason score 2-6, and prostate-specific antigen (PSA) greater than 10 ng/mL but no greater than 100 ng/mL T1b-4, Gleason score 7, and PSA less than 20 ng/mL T1b-1c, Gleason score 8-10, and PSA less than 20 ng/mL Radiotherapy completed within the past 6 months to 5 years Pretreatment (before enrollment on this study) erectile dysfunction as measured by International Index of Erectile Function Question #1 Erectile dysfunction before starting prostate cancer therapy allowed Patients without partners or without partners willing to participate allowed PATIENT CHARACTERISTICS: Age 18 and over Performance status Zubrod 0-2 Life expectancy Not specified Hematopoietic Not specified Hepatic Not specified Renal Not specified Cardiovascular No myocardial infarction within the past year Other No other invasive cancer within the past 5 years except localized basal cell or squamous cell skin cancer (stage 0-II) No anatomical genital abnormalities or concurrent conditions that would prohibit sexual intercourse or preclude study participation No other major medical or psychiatric illness that would preclude study participation PRIOR CONCURRENT THERAPY: Biologic therapy Not specified Chemotherapy Not specified Endocrine therapy More than 6 months since prior androgen suppression (e.g., leuprolide or goserelin), antiandrogen (e.g., bicalutamide, flutamide, or nilutamide), or estrogenic (e.g., diethylstilbestrol) agents Radiotherapy See Disease Characteristics Surgery No prior penile implant No prior bilateral orchiectomy Other No concurrent sildenafil No concurrent participation in another medical research study to treat prostate cancer No concurrent organic nitrate or requirement for nitrates (e.g., nitroglycerin as needed) No concurrent ketoconazole, itraconazole, or erythromycin No concurrent use of mechanical (vacuum) devices or intracorporeal, intraurethral, topical, or oral agents for erectile dysfunction

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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Male

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Supportive Care
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Sildenafil citrate<br>Sildenafil with dose escalation as needed from 50 mg to 100 mg/day prn for 12 weeks. | Drug: sildenafil citrate<br> <br> |
| Placebo Comparator: Placebo<br>Placebo with similar dose escalation opportunity for 12 weeks. | Other: Placebo<br>* Placebo<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Ability to obtain an erection, as measured by question 1 on the IIEF |  | From baseline to 12 weeks from the start of drug after crossover | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Overall sexual function and satisfaction as measured by the Sexual Adjustment Questionnaire (SAQ) |  | From baseline to 12 weeks from the start of drug after crossover | 
| Partner sexual satisfaction as measured by the SAQ-Partner |  | From baseline to 12 weeks from the start of drug after crossover | 
| Patient and spouse marital adjustment as measured by the Locke's Marital Adjustment Test |  | From baseline to 12 weeks from the start of drug after crossover | 
| Predictors of erectile dysfunction therapy |  | From baseline to 12 weeks from the start of drug after crossover | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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sexual dysfunction, sexuality and reproductive issues, radiation toxicity, stage IIB prostate cancer, stage IIA prostate cancer, stage III prostate cancer, psychosocial effects of cancer and its treatment