The classic website will no longer be available as of June 25, 2024. Please use the modernized
Working… Menu

L-Arginine Supplementation With or Without Enzyme Inhibitors Treating Erectile Function of Prostate Cancer Survivors

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT01105130
Recruitment Status : Completed
First Posted : April 16, 2010
Results First Posted : July 21, 2015
Last Update Posted : September 28, 2021
National Cancer Institute (NCI)
Information provided by (Responsible Party):
Wake Forest University Health Sciences

Brief Summary:

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.

Condition or disease Intervention/treatment Phase
Male Erectile Disorder Prostate Cancer Radiation Toxicity Other: Placebo Drug: Oral L-Arginine Phase 2

Detailed Description:



  • 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.

Layout table for study information
Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 140 participants
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
Actual Study Start Date : October 1, 2010
Actual Primary Completion Date : February 4, 2014
Actual Study Completion Date : February 4, 2014

Resource links provided by the National Library of Medicine

MedlinePlus related topics: Prostate Cancer

Arm Intervention/treatment
Placebo Comparator: Arm I - Placebo
Patients receive oral placebo twice daily (total of 6 capsules per day).
Other: Placebo
Given orally

Experimental: Arm II - low dose
Patients receive oral L-arginine and oral placebo twice daily (total of 3 capsules of each per day).
Other: Placebo
Given orally

Drug: Oral L-Arginine
Given orally 3 capsules ArginMax and 3 Placebo capsules
Other Names:
  • ArginMax
  • Placebo

Experimental: Arm III - high dose
Oral L-arginine twice daily = 6 capsules per day.
Drug: Oral L-Arginine
Given orally 3 capsules ArginMax and 3 Placebo capsules
Other Names:
  • ArginMax
  • Placebo

Drug: Oral L-Arginine
Patients will take 6 capsules of ArginMax twice daily
Other Name: ArginMax

Primary Outcome Measures :
  1. International Index of Erectile Function (IIEF) [ 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.

Secondary Outcome Measures :
  1. Retention [ Time Frame: 8 weeks ]
    Retention is the percentage of participants who complete the 8 week visit.

  2. Adherence [ Time Frame: 8 weeks ]
    Adherence is the percentage of prescribed pills taken by the participants

  3. Assessment of 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.

Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.

Layout table for eligibility information
Ages Eligible for Study:   18 Years and older   (Adult, Older Adult)
Sexes Eligible for Study:   Male
Accepts Healthy Volunteers:   No


  • Male prostate cancer survivor previously treated with radiotherapy and who identifies himself as concerned with sexual quality of life, including erectile dysfunction. (seed implants are eligible)
  • Had successful sexual activity prior to the commencement of radiotherapy.
  • Erectile dysfunction, defined as inability to achieve or maintain an erection sufficient for satisfactory sexual performance
  • Interested in sexual activity and agrees to make at least one sexual intercourse attempt with a partner every week during the study.
  • The usage of PDE-5 inhibitors will be voluntary and will serve as a stratification factor. Patients taking PDE-5 inhibitors must agree to assume the responsibility for the cost of PDE-5 inhibitor treatment during the protocol period (8 week period) as this is not covered in the cost of the trial.
  • Patients currently taking PDE-5 inhibitors sildenafil (Viagra®, Pfizer Pharmaceuticals), tadalafil(Cialis®, Lilly ICOS, LLC), and vardenafil (Levitra®, Bayer Healthcare / Schering Plough Corp.)must agree to take the medication only as prescribed by their treating physician.
  • Patients taking PDE-5 inhibitors as part of this study must be on a stable dose of drug for at least one month prior to study entry.
  • Must be able to take oral medications.
  • > 6 months following completion of all cancer therapy
  • No evidence of prostate cancer
  • Prior malignancies allowed if no evidence of recurrent disease.
  • If previously taken LHRH agonist androgen suppression (e.g, Lupron, Zoladex), anti-androgen (e.g., Casodex, Eulexin, Nilandron), or estrogenic (e.g., diethylstilbestrol) agents, serum testosterone must have returned to the laboratory normal range
  • No planned surgery while on protocol or for 4 weeks following completion of protocol
  • Prior cystoscopy is permitted.
  • Age > 18
  • ECOG performance status 0/1.
  • Patients must agree not to start taking an herbal product for erectile dysfunction during the eight weeks of study intervention.


  • No other concurrent erectile dysfunction therapies permitted (i.e. vacuum pump,cavernosal injections, and other drug therapies). Past use of these and other therapies permitted if the patient can meet the inclusion criteria above.
  • No testosterone supplementation permitted.
  • Use of LHRH agonist androgen suppression (e.g, Lupron, Zoladex), anti- androgen (e.g., Casodex,Eulexin, Nilandron), or estrogenic (e.g., diethylstilbestrol) agents within the last 6 months.
  • Prior prostate or lower genitourinary surgery (bladder, penis, urethra, testicles)including transurethral resection of prostate (TURP). (Prior vasectomy is allowed)
  • Serious cardiovascular disease (unstable angina, supraventricular arrhythmia, myocardial infarction, symptomatic congestive heart failure, cardiac arrhythmia, coronary artery bypass surgery within 6 months prior to registration).
  • Hypotension (<90/50mm Hg), or uncontrolled hypertension (>170/100 mm Hg)
  • Stroke or spinal cord injury within 6 months before registration.
  • Patients on Persantine, heparin, Lovenox, warfarin, ginkgo biloba, Plavix, Disalcid, other blood-thinning medication or with a history of bleeding disorders will be excluded.(Aspirin < 325mg allowed)
  • Current use of cimetidine, ketoconazole, itraconazole, erythromycin, or ritonavir. Major medical or psychiatric illness which, in the opinion of the investigator, would prevent completion of treatment or would interfere with follow-up.
  • Current or prior use of any organic nitrate within the last 6 months (e.g., use of nitroglycerin)
  • May not receive other investigational agents or devices during 30 days prior to start of study drug.
  • History of allergic reactions attributed to compounds of similar chemical or biologic composition to ArginMax (l-arginine, ginseng, or ginkgo biloba)

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT01105130

Layout table for location information
United States, North Carolina
W F Baptist Health
Winston-Salem, North Carolina, United States, 27157
Sponsors and Collaborators
Wake Forest University Health Sciences
National Cancer Institute (NCI)
Layout table for investigator information
Study Chair: James J. Urbanic, MD Wake Forest University Health Sciences
Layout table for additonal information
Responsible Party: Wake Forest University Health Sciences Identifier: NCT01105130    
Other Study ID Numbers: IRB00012793
U10CA081851 ( U.S. NIH Grant/Contract )
REBACCCWFU 98110 ( Other Identifier: NCI )
First Posted: April 16, 2010    Key Record Dates
Results First Posted: July 21, 2015
Last Update Posted: September 28, 2021
Last Verified: September 2021
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: No

Layout table for additional information
Studies a U.S. FDA-regulated Drug Product: Yes
Studies a U.S. FDA-regulated Device Product: No
Keywords provided by Wake Forest University Health Sciences:
radiation toxicity
male erectile disorder
prostate cancer
Additional relevant MeSH terms:
Layout table for MeSH terms
Prostatic Neoplasms
Erectile Dysfunction
Genital Neoplasms, Male
Urogenital Neoplasms
Neoplasms by Site
Genital Diseases, Male
Genital Diseases
Urogenital Diseases
Prostatic Diseases
Male Urogenital Diseases
Sexual Dysfunction, Physiological
Sexual Dysfunctions, Psychological
Mental Disorders