L-Arginine Supplementation With or Without Enzyme Inhibitors Treating Erectile Function of Prostate Cancer Survivors
RATIONALE: L-arginine supplements may improve the quality of life and erectile function in men who are prostate cancer survivors.
PURPOSE: This randomized phase II trial is studying how well L-arginine supplementation works with or without enzyme inhibitors in treating erectile function and quality of life of prostate cancer survivors previously treated with radiation therapy.
|Male Erectile Disorder Prostate Cancer Radiation Toxicity||Other: Placebo Dietary Supplement: Oral L-Arginine|
|Study Design:||Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary Purpose: Supportive Care
|Official Title:||A Randomized Phase II Dose Finding Study of ArginMax for Its Effect on Erectile Function and Quality of Life in Survivors of Prostate Cancer Previously Treated With Radiotherapy|
- Erectile Function [ Time Frame: 8 weeks ]The International Index of Erectile Function (IIEF) questionnaire consists of 15 questions, each of which is scored on a 0 to 5 or 1 to 5 scale. It is comprised of five domains, each scored as the sum of 2 to 5 questions. Erectile function is the sum of six questions with a range from 1 to 30. Higher scores indicate better functioning.
- Retention [ Time Frame: 8 weeks ]Retention is the percentage of participants who complete the 8 week visit.
- Adherence [ Time Frame: 8 weeks ]Adherence is the percentage of prescribed pills taken by the participants
- Quality of Life [ Time Frame: 8 weeks ]Quality of life is quantified by the Functional Assessment of Cancer Therapy - Prostate (FACT_P) questionnaire. The FACT questionnaire is comprised of four subscales - social, emotional, functional, and physical. Each subscale is obtained by summing over 6-7 items, each of which is coded on a 0 to 4 scale. Negatively worded questions are reverse scored and higher scores for each subscale indicate better HRQOL. The social, functional, and physical subscales range from 0 to 28 while the emotional subscale ranges from 0 to 24. The overall score (FACT-G) is the sum over the four subscales and ranges from 0 to 108. Patients also completed 12 questions related to prostate cancer, and the prostate subscale score is the sum of those responses (with some items reverse scored). Scores range from 0 to 48, and as with the other FACT subscales higher scores indicate better HRQOL. FACT-P is the sum of FACT-G and the prostate subscale. This questionnaire was added half-way through the study.
|Study Start Date:||October 2010|
|Study Completion Date:||January 2014|
|Primary Completion Date:||January 2014 (Final data collection date for primary outcome measure)|
Placebo Comparator: Arm I - Placebo
Patients receive oral placebo twice daily (total of 6 capsules per day).
Experimental: Arm II - low dose
Patients receive oral L-arginine and oral placebo twice daily (total of 3 capsules of each per day).
Given orallyDietary Supplement: Oral L-Arginine
Given orally 3 capsules ArginMax and 3 Placebo capsules
Experimental: Arm III - high dose
Oral L-arginine twice daily = 6 capsules per day.
Dietary Supplement: Oral L-Arginine
Given orally 3 capsules ArginMax and 3 Placebo capsules
Other Names:Dietary Supplement: Oral L-Arginine
Patients will take 6 capsules of ArginMax twice daily
Other Name: ArginMax
- To determine the "best dose" (defined as the dose that shows the greatest improvement in the erectile function domain of the International Index of Erectile Function [IIEF] after 8 weeks of therapy) of an L-arginine/Korean ginseng/gingko biloba/damiana-based supplement (L-arginine) to be used in a subsequent phase III trial in prostate cancer survivors previously treated with radiotherapy.
- Evaluate the toxicity of treatment with L-arginine with or without phosphodiesterase-5 inhibitors.
- Estimate trial accrual, retention, adherence, and variability.
- Assess changes in quality of life (QOL) and sexual function as defined by changes in the QOL of these patients using the Expanded Prostate Cancer Index Composite, changes in the other domains of the IIEF (i.e., orgasmic function, sexual desire, intercourse satisfaction, and overall satisfaction), changes in the Sexual Encounter Profile, and changes in the percentage of "yes" (positive) responses to either of the two global efficacy questions.
OUTLINE: Patients are stratified according to age (< 65 years vs ≥ 65 years) and current use of phosphodiesterase-5 (PDE-5) inhibitors (yes vs no). Patients are randomized to 1 of 3 treatment arms.
- Arm I: Patients receive oral placebo twice daily (total of 6 capsules per day).
- Arm II: Patients receive oral L-arginine and oral placebo twice daily (total of 3 capsules of each per day).
- Arm III: Patients receive oral L-arginine twice daily (total of 6 capsules per day).
In all arms, treatment continues for 8 weeks in the absence of unacceptable toxicity.
Patients may also receive oral sildenafil, tadalafil, or vardenafil (PDE-5 inhibitors).
Patients complete the International Index of Erectile Function and the Expanded Prostate Cancer Index Composite-26 at baseline and at weeks 4 and 8. Patients also complete the Sexual Encounter Profile Questionnaire, FACT-P, and the Global Efficacy Questionnaire at weeks 4 and 8.
Please refer to this study by its ClinicalTrials.gov identifier: NCT01105130
|United States, North Carolina|
|W F Baptist Health|
|Winston-Salem, North Carolina, United States, 27157|
|Study Chair:||James J. Urbanic, MD||Wake Forest University Health Sciences|