Official Title: “This Protocol is a Randomized Prospective Study Comparing Prophylactic and on Demand Sildenafil Citrate Usage Administered During and After Radiotherapy With or Without Hormone Therapy Versus Radiotherapy With or Without Hormone Therapy Alone for the Preservation of Erectile Function After Therapy for Potent Patients With Clinically Localized Prostate Cancer”

Radiation sometimes affects the ability for a person to have a normal erection. Complete loss of erections after radiation treatment can happen in 40-50% of treated patients. There are medications, like sildenafil (also known as Viagra), that can help the ability to get back erections in almost 70% of such patients.

The purpose of this study is to see if taking Viagra every day starting right before, during and for about 6 months after treatment, could reduce the risk of long-term erectile dysfunction.

Study Type: Interventional

Study Design: Prevention, Randomized, Double Blind (Subject, Investigator), Placebo Control, Parallel Assignment

Study Primary Completion Date: February 2010

This protocol is a randomized prospective study comparing prophylactic sildenafil citrate usage administered during and after radiotherapy/hormone therapy for the preservation of erectile function versus radiotherapy alone for patients with clinically localized prostate cancer. The primary objective of this protocol is to determine if prophylactic sildenafil citrate used before, during and after a course of radiotherapy (external beam radiotherapy or brachytherapy) can prevent loss of spontaneous erectile function two years following radiation treatment. Secondary endpoints of this study include the determination whether prophylactic use of sildenafil citrate during radiotherapy may improve the long-term response to the drug following treatment. An additional endpoint will be to determine if sildenafil citrate used during a course of external beam radiotherapy or brachytherapy will reduce acute and late urinary effects from radiotherapy. - To determine if prophylactic sildenafil citrate used before, during and after a course of radiotherapy (external beam radiotherapy or brachytherapy) can prevent loss of spontaneous erectile function two years from the start of radiation treatment (primary objective). - To determine if the prophylactic use of sildenafil citrate during radiotherapy may improve the long-term response to the drug following treatment (secondary objective). - To determine if sildenafil citrate used during a course of external beam radiotherapy or brachytherapy among patients will reduce acute and late urinary effects of radiotherapy (secondary objective). - To determine if prophylactic and on demand usage of Sildenafil Citrate diminish the time to restoration of erectile function after radiation therapy with or without hormone therapy. - To determine the impact of dosimetry and radiation exposure to both the neurovascular bundle and the bulb of the penis on erectile function preservation in the study population undergoing brachytherapy and hormone therapy. - To assess the impact on quality of life following prophylactic and on demand Sildenafil Citrate usage in the study population. - To determine the relationship between testosterone levels, erectile function and efficacy of prophylactic and on demand Sildenafil Citrate usage in the study population.

Intervention(s) in this Clinical Trial

• Drug: sildenafil citrate
  • Hormone therapy patients will be instructed to begin the study drug simultaneously or within 1 month of start of hormone therapy. These patients will then continue to take the study drug for approximately 6 months following start of radiotherapy. Hormone therapy patients will complete assessments at baseline (within 4 weeks of start of study treatment) and at approximately months 2 and 1 (only IIEF and QOL) before start of radiotherapy, at start of radiotherapy and at months 3, 6, 9, 12 18 and 24 from start of radiotherapy.
• Drug: placebo tablets
  • Non-hormone therapy patients will be instructed to begin the study drug 3 days prior to start of radiotherapy. Patients beginning study drug anytime between 3 days before start of radiotherapy and first day of radiotherapy will also be acceptable. These patients will then continue to take the study drug for approximately 6 months following start of radiotherapy. Assessments (IIEF, IPSS, QOL) will be completed by non-hormone therapy patients at baseline (within 4 weeks of start of study treatment) and at approximately months 3, 6, 9, 12, 18 and 24 from start of radiotherapy.
• Behavioral: questionaire assessments
  • Questionnaire assessment

Arms, Groups and Cohorts in this Clinical Trial

• Active Comparator: 1
  • radiotherapy with hormones, questionaire assessments
• Placebo Comparator: 2
  • radiotherapy without hormones, questionaire assessments

Primary Measures

• To determine if prophylactic sildenafil citrate used before, during and after a course of radiotherapy (external beam RT or brachytherapy)/hormone therapy can prevent loss of spontaneous erectile function 2 years from the start of radiation treatment
  • Time Frame: 2 years from start of RT
    Safety Issue?: No

Secondary Measures

• To determine if the prophylactic use of sildenafil citrate during radiotherapy may improve the long-term response to the drug following treatment
  • Time Frame: 2 years from start of RT
    Safety Issue?: No

Inclusion Criteria:

• To receive external beam radiation therapy and/or brachytherapy for biopsy-proven prostate cancer.
• Baseline International Index of Erectile Function (IIEF) erectile function domain score >= 17.
• Patients receiving radiotherapy with hormone therapy undergoing a maximum of 9 months of hormone therapy will be acceptable.

Exclusion Criteria:

• IIEF erectile function domain score < 17 pre-therapy
• Current routine use of erectogenic agents (use of agents > 4 times per month would constitute "routine use")
• Neoadjuvant androgen deprivation therapy (intake of bicalutamide alone would not constitute exclusion from study entry)
• Non-organ confined disease
• Pre-existing Peyronie's disease
• Prior prostate surgery, prostate radiotherapy or cryotherapy
• Currently taking nitrate medication
• Currently taking 2 Flomax
• Present at baseline with chronic angina requiring nitrates, angina occurring during sexual intercourse or unstable angina within the last 6 months.
• History of myocardial infarction, coronary artery bypass graft surgery or percutaneous coronary intervention within 90 days of baseline visit.
• History of significant cardiac conduction defect within 90 days of baseline visit.
• Exhibit systolic blood pressure > 170 or < 90 mm Hg or diastolic blood pressure > 100 or < 50 mm Hg at baseline visit or have a history of malignant hypertension
• Have any condition that would interfere with the subject's ability to provide informed consent or comply with study instructions, would place subject at increased risk, or might confound the interpretation of the study results
• Currently receive treatment with nitrates, cancer chemotherapy, or antiandrogens (except finasteride taken as Propecia or Proscar)
• Have a history of drug, alcohol, or substance abuse within the past 6 months, as assessed by the investigator.
• Have previously received sildenafil citrate treatment that, in the investigator's opinion, has been ineffective.

Gender Eligibility for this Clinical Trial: Male

Minimum Age for this Clinical Trial: N/A

Maximum Age for this Clinical Trial: N/A

Are Healthy Volunteers Accepted for this Clinical Trial?: No

Lead Sponsor: Memorial Sloan-Kettering Cancer Center

Overall Clinical Trial Officials and Contacts

Michael J Zelefsky, M.D. Principal Investigator Memorial Sloan-Kettering Cancer Center  

Overall Contact: Michael J. Zelefsky, M.D. 212-639-6802 zelefskm@mskcc.org

Information obtained from ClinicalTrials.gov on October 10, 2008

Link to the current ClinicalTrials.gov record. http://clinicaltrials.gov/show/NCT00142506

Study ID Number: 05-007

ClinicalTrials.gov Identifier: NCT00142506

Health Authority: United States: Institutional Review Board

Memorial Sloan-Kettering Cancer Center