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NCT00931528 · OUTCOME

Percentage of Patients Maintaining Spontaneous (Off-drug) EF at Years 1 and 2 After Initiation of RT

Tadalafil in Preventing Erectile Dysfunction in Patients With Prostate Cancer Treated With Radiation Therapy · Source last updated 2018-02-14

Results reported by the registry submitting party. Population, time horizon, units and missing values must be read together.

Measure
NUMBER
Unit
percentage of participants
Interval / dispersion
95% Confidence Interval
Time frame
Baseline, 1 and 2 years from the start of tadalafil or placebo

What was measured

The International Index of Erectile Function (IIEF) is a validated 15-item for measuring patient-reported erectile function. Question 1 asks "How often were you able to get an erection during sexual activity?" Responses ranged from 0=no sexual activity, to 5=Almost always or always. Higher scores indicated better functioning. All patients have erectile function prior to initiation of RT, indicated by a score of 3, 4, or 5. Patients with a lower IIEF Q1 score at weeks 28-30 than at baseline will have less erectile function and be categorized as nonresponders. Patients with similar or improved erectile function will be categorized as responders (maintaining). Patient-related predictors of at erectile function at Years 1 and 2 are also reported with this outcome measure.

Analysis population: All randomized eligible patients with IIEF at both baseline and corresponding time point.

Groups in this outcome

Tadalafil

Beginning ≤ 7 days after the start of radiotherapy, patients receive oral tadalafil once daily for 24 weeks.

Placebo

Beginning ≤ 7 days after the start of radiotherapy, patients receive oral placebo once daily for 24 weeks.

Group identifiers and denominators belong to this outcome only. They may differ in another outcome or in safety reporting.

Analysis denominator · Participants

GroupSource count
Tadalafil109
Placebo108

Reported measurements

Year 1

Analysis denominator · Participants

GroupSource count
Tadalafil54
Placebo49
Values in percentage of participants · Interval/dispersion: 95% Confidence Interval
GroupValueSpreadLowerUpperComment
Tadalafil72.2Not reported60.384.1Not reported
Placebo71.4Not reported58.784.1Not reported
Year 2

Analysis denominator · Participants

GroupSource count
Tadalafil57
Placebo49
Values in percentage of participants · Interval/dispersion: 95% Confidence Interval
GroupValueSpreadLowerUpperComment
Tadalafil68.4Not reported56.380.5Not reported
Placebo63.3Not reported49.876.8Not reported

Source statistical analyses

Group order, estimate direction, methods and comments are retained. No treatment ranking is inferred.

  1. group Description
    Year 1
    group Ids
    1. OG000
    2. OG001
    non Inferiority Type
    SUPERIORITY
    p Value
    0.93
    statistical Comment
    2-sided significance level = 0.05
    statistical Method
    Chi-squared
  2. group Description
    Year 2
    group Ids
    1. OG000
    2. OG001
    non Inferiority Type
    SUPERIORITY
    p Value
    0.58
    statistical Comment
    2-sided significance level = 0.05
    statistical Method
    Chi-squared
  3. group Description
    Year 1: Logistic regression using generalized estimating equations was performed modeling the probability of non-responders. Only treatment arm (Placebo vs. Tadalafil), age (\> 65 vs. other), RT method (External RT vs. brachytherapy), and significant pretreatment characteristics \[none\] were retained in the model. (Dropped pretreatment characteristics: ethnicity, Zubrod, N stage, T stage, PSA.) The results for each explanatory variable are reported separately. Treatment arm is reported here.
    group Ids
    1. OG000
    2. OG001
    non Inferiority Type
    SUPERIORITY
    p Value
    0.9501
    statistical Method
    Regression, Logistic
  4. group Description
    Year 1: Logistic regression using generalized estimating equations was performed modeling the probability of non-responders. Only treatment arm (Placebo vs. Tadalafil), age (\> 65 vs. other), RT method (External RT vs. brachytherapy), and significant pretreatment characteristics \[none\] were retained in the model. (Dropped pretreatment characteristics: ethnicity, Zubrod, N stage, T stage, PSA.) The results for each explanatory variable are reported separately. RT method is reported here.
    group Ids
    1. OG000
    2. OG001
    non Inferiority Type
    SUPERIORITY
    p Value
    0.1020
    statistical Method
    Regression, Logistic
  5. group Description
    Year 1: Logistic regression using generalized estimating equations was performed modeling the probability of non-responders. Only treatment arm (Placebo vs. Tadalafil), age (\> 65 vs. other), RT method (External RT vs. brachytherapy), and significant pretreatment characteristics \[none\] were retained in the model. (Dropped pretreatment characteristics: ethnicity, Zubrod, N stage, T stage, PSA.) The results for each explanatory variable are reported separately. Age is reported here.
    group Ids
    1. OG000
    2. OG001
    non Inferiority Type
    SUPERIORITY
    p Value
    0.1855
    statistical Method
    Regression, Logistic
  6. group Description
    Year 2: Logistic regression using generalized estimating equations was performed modeling the probability of non-responders. Only treatment arm (Placebo vs. Tadalafil), age (\> 65 vs. other), RT method (External RT vs. brachytherapy), and significant pretreatment characteristics \[N stage (NX)\] were retained in the model. (Dropped pretreatment characteristics: ethnicity, Zubrod, T stage, PSA.) The results for each explanatory variable are reported separately. Treatment arm is reported here.
    group Ids
    1. OG000
    2. OG001
    non Inferiority Type
    SUPERIORITY
    p Value
    0.5739
    statistical Method
    Regression, Logistic
  7. group Description
    Year 2: Logistic regression using generalized estimating equations was performed modeling the probability of non-responders. Only treatment arm (Placebo vs. Tadalafil), age (\> 65 vs. other), RT method (External RT vs. brachytherapy), and significant pretreatment characteristics \[N stage (NX)\] were retained in the model. (Dropped pretreatment characteristics: ethnicity, Zubrod, T stage, PSA.) The results for each explanatory variable are reported separately. RT method is reported here.
    group Ids
    1. OG000
    2. OG001
    non Inferiority Type
    SUPERIORITY
    p Value
    0.0422
    statistical Method
    Regression, Logistic
  8. group Description
    Year 2: Logistic regression using generalized estimating equations was performed modeling the probability of non-responders. Only treatment arm (Placebo vs. Tadalafil), age (\> 65 vs. other), RT method (External RT vs. brachytherapy), and significant pretreatment characteristics \[N stage (NX)\] were retained in the model. (Dropped pretreatment characteristics: ethnicity, Zubrod, T stage, PSA.) The results for each explanatory variable are reported separately. Age is reported here.
    group Ids
    1. OG000
    2. OG001
    non Inferiority Type
    SUPERIORITY
    p Value
    0.5237
    statistical Method
    Regression, Logistic
  9. group Description
    Year 2: Logistic regression using generalized estimating equations was performed modeling the probability of non-responders. Only treatment arm (Placebo vs. Tadalafil), age (\> 65 vs. other), RT method (External RT vs. brachytherapy), and significant pretreatment characteristics \[N stage (NX)\] were retained in the model. (Dropped pretreatment characteristics: ethnicity, Zubrod, T stage, PSA.) The results for each explanatory variable are reported separately. N Stage is reported here.
    group Ids
    1. OG000
    2. OG001
    non Inferiority Type
    SUPERIORITY
    p Value
    0.4770
    statistical Method
    Regression, Logistic
Complete source fields
analyses
  1. group Description
    Year 1
    group Ids
    1. OG000
    2. OG001
    non Inferiority Type
    SUPERIORITY
    p Value
    0.93
    statistical Comment
    2-sided significance level = 0.05
    statistical Method
    Chi-squared
  2. group Description
    Year 2
    group Ids
    1. OG000
    2. OG001
    non Inferiority Type
    SUPERIORITY
    p Value
    0.58
    statistical Comment
    2-sided significance level = 0.05
    statistical Method
    Chi-squared
  3. group Description
    Year 1: Logistic regression using generalized estimating equations was performed modeling the probability of non-responders. Only treatment arm (Placebo vs. Tadalafil), age (\> 65 vs. other), RT method (External RT vs. brachytherapy), and significant pretreatment characteristics \[none\] were retained in the model. (Dropped pretreatment characteristics: ethnicity, Zubrod, N stage, T stage, PSA.) The results for each explanatory variable are reported separately. Treatment arm is reported here.
    group Ids
    1. OG000
    2. OG001
    non Inferiority Type
    SUPERIORITY
    p Value
    0.9501
    statistical Method
    Regression, Logistic
  4. group Description
    Year 1: Logistic regression using generalized estimating equations was performed modeling the probability of non-responders. Only treatment arm (Placebo vs. Tadalafil), age (\> 65 vs. other), RT method (External RT vs. brachytherapy), and significant pretreatment characteristics \[none\] were retained in the model. (Dropped pretreatment characteristics: ethnicity, Zubrod, N stage, T stage, PSA.) The results for each explanatory variable are reported separately. RT method is reported here.
    group Ids
    1. OG000
    2. OG001
    non Inferiority Type
    SUPERIORITY
    p Value
    0.1020
    statistical Method
    Regression, Logistic
  5. group Description
    Year 1: Logistic regression using generalized estimating equations was performed modeling the probability of non-responders. Only treatment arm (Placebo vs. Tadalafil), age (\> 65 vs. other), RT method (External RT vs. brachytherapy), and significant pretreatment characteristics \[none\] were retained in the model. (Dropped pretreatment characteristics: ethnicity, Zubrod, N stage, T stage, PSA.) The results for each explanatory variable are reported separately. Age is reported here.
    group Ids
    1. OG000
    2. OG001
    non Inferiority Type
    SUPERIORITY
    p Value
    0.1855
    statistical Method
    Regression, Logistic
  6. group Description
    Year 2: Logistic regression using generalized estimating equations was performed modeling the probability of non-responders. Only treatment arm (Placebo vs. Tadalafil), age (\> 65 vs. other), RT method (External RT vs. brachytherapy), and significant pretreatment characteristics \[N stage (NX)\] were retained in the model. (Dropped pretreatment characteristics: ethnicity, Zubrod, T stage, PSA.) The results for each explanatory variable are reported separately. Treatment arm is reported here.
    group Ids
    1. OG000
    2. OG001
    non Inferiority Type
    SUPERIORITY
    p Value
    0.5739
    statistical Method
    Regression, Logistic
  7. group Description
    Year 2: Logistic regression using generalized estimating equations was performed modeling the probability of non-responders. Only treatment arm (Placebo vs. Tadalafil), age (\> 65 vs. other), RT method (External RT vs. brachytherapy), and significant pretreatment characteristics \[N stage (NX)\] were retained in the model. (Dropped pretreatment characteristics: ethnicity, Zubrod, T stage, PSA.) The results for each explanatory variable are reported separately. RT method is reported here.
    group Ids
    1. OG000
    2. OG001
    non Inferiority Type
    SUPERIORITY
    p Value
    0.0422
    statistical Method
    Regression, Logistic
  8. group Description
    Year 2: Logistic regression using generalized estimating equations was performed modeling the probability of non-responders. Only treatment arm (Placebo vs. Tadalafil), age (\> 65 vs. other), RT method (External RT vs. brachytherapy), and significant pretreatment characteristics \[N stage (NX)\] were retained in the model. (Dropped pretreatment characteristics: ethnicity, Zubrod, T stage, PSA.) The results for each explanatory variable are reported separately. Age is reported here.
    group Ids
    1. OG000
    2. OG001
    non Inferiority Type
    SUPERIORITY
    p Value
    0.5237
    statistical Method
    Regression, Logistic
  9. group Description
    Year 2: Logistic regression using generalized estimating equations was performed modeling the probability of non-responders. Only treatment arm (Placebo vs. Tadalafil), age (\> 65 vs. other), RT method (External RT vs. brachytherapy), and significant pretreatment characteristics \[N stage (NX)\] were retained in the model. (Dropped pretreatment characteristics: ethnicity, Zubrod, T stage, PSA.) The results for each explanatory variable are reported separately. N Stage is reported here.
    group Ids
    1. OG000
    2. OG001
    non Inferiority Type
    SUPERIORITY
    p Value
    0.4770
    statistical Method
    Regression, Logistic
classes
  1. categories
    1. measurements
      1. group Id
        OG000
        lower Limit
        60.3
        upper Limit
        84.1
        value
        72.2
      2. group Id
        OG001
        lower Limit
        58.7
        upper Limit
        84.1
        value
        71.4
    denoms
    1. counts
      1. group Id
        OG000
        value
        54
      2. group Id
        OG001
        value
        49
      units
      Participants
    title
    Year 1
  2. categories
    1. measurements
      1. group Id
        OG000
        lower Limit
        56.3
        upper Limit
        80.5
        value
        68.4
      2. group Id
        OG001
        lower Limit
        49.8
        upper Limit
        76.8
        value
        63.3
    denoms
    1. counts
      1. group Id
        OG000
        value
        57
      2. group Id
        OG001
        value
        49
      units
      Participants
    title
    Year 2
denoms
  1. counts
    1. group Id
      OG000
      value
      109
    2. group Id
      OG001
      value
      108
    units
    Participants
description
The International Index of Erectile Function (IIEF) is a validated 15-item for measuring patient-reported erectile function. Question 1 asks "How often were you able to get an erection during sexual activity?" Responses ranged from 0=no sexual activity, to 5=Almost always or always. Higher scores indicated better functioning. All patients have erectile function prior to initiation of RT, indicated by a score of 3, 4, or 5. Patients with a lower IIEF Q1 score at weeks 28-30 than at baseline will have less erectile function and be categorized as nonresponders. Patients with similar or improved erectile function will be categorized as responders (maintaining). Patient-related predictors of at erectile function at Years 1 and 2 are also reported with this outcome measure.
dispersion Type
95% Confidence Interval
groups
  1. description
    Beginning ≤ 7 days after the start of radiotherapy, patients receive oral tadalafil once daily for 24 weeks.
    id
    OG000
    title
    Tadalafil
  2. description
    Beginning ≤ 7 days after the start of radiotherapy, patients receive oral placebo once daily for 24 weeks.
    id
    OG001
    title
    Placebo
param Type
NUMBER
population Description
All randomized eligible patients with IIEF at both baseline and corresponding time point.
reporting Status
POSTED
time Frame
Baseline, 1 and 2 years from the start of tadalafil or placebo
title
Percentage of Patients Maintaining Spontaneous (Off-drug) EF at Years 1 and 2 After Initiation of RT
type
SECONDARY
unit Of Measure
percentage of participants

Download exact source JSON → · Snapshot ctgov-results-191f4516d4760045304b24a0

Preserved source evidence · Not medical advice