A Phase 3 interventional study of Allopurinol and Placebo in Cardiovascular Diseases, Heart Diseases and Hypertension, sponsored by University of Florida. Completed at 1 site in United States. Open to participants aged 18 Years to 65 Years. Per ClinicalTrials.gov, last updated 2013-07-26.
Sponsored by University of Florida · Phase 3, Interventional, and Treatment
This study will test the hypothesis that the administration of a xanthine oxidase inhibitor (allopurinol) will prevent thiazide-induced hyperuricemia, which will result in better blood pressure (BP) control in African Americans.
Thiazide diuretics when used in the treatment of hypertension are associated with many metabolic side effects, including hyperuricemia, gout, insulin resistance, and hyperlipidemia. Each of these conditions is already highly prevalent in African Americans. Our hypothesis is that thiazide-induced hyperuricemia decreases the efficacy of thiazides in controlling BP, leads to endothelial dysfunction, and increases the incidence of insulin resistance and impaired glucose tolerance. This hypothesis will be tested in a randomized, double-blind, placebo-controlled clinical trial of 8-10 weeks duration in which a total of 100 African American patients with hypertension will be enrolled, randomized, and treated as follows:
The allopurinol (or placebo) dose will be adjusted to achieve serum uric acid levels between 4 and 5.5 mg/dL after 2 weeks on drug. All subjects will receive a low-sodium diet. The primary endpoint is reduction in systolic BP. Secondary endpoints measure endothelial function, ambulatory blood pressure, body composition, systemic inflammation, metabolic parameters, oxidant stress, and renal hemodynamics.
6,689 studies on the registry are indexed under Hypertension; 965 are open to participants now.
This study's enrollment of 150 is above the median of 90 across 4,995 interventional studies indexed under Hypertension.
Browse Hypertension studies →University of Florida is the lead sponsor of 1,254 studies on the registry; 201 are open to participants now.
Of its 170 completed or terminated interventional studies of FDA-regulated products, 136 (80%) have results posted.
Counted across the registry records on this site, refreshed daily.
Exclusion Criteria:
Chlorthalidone 25 mg and Potassium Chloride 40-50meq were given daily for 5 weeks before baseline visit for testing. After baseline testing was completed, Allopurinol 300mg daily was added for 8-10 weeks at which time testing was repeated.
Drug: Allopurinol · Drug: Chlorthalidone · Drug: Potassium chloride
Chlorthalidone 25 mg and Potassium Chloride 40-50meq were given daily for 5 weeks before baseline visit for testing. After baseline testing was completed, a Placebo,matched in appearance to Allopurinol, was added daily for 8-10 weeks, at which time testing was repeated.
Drug: Placebo · Drug: Chlorthalidone · Drug: Potassium chloride
Allopurinol (300 mg capsule) was given for 8-10 weeks compared to placebo group after initial baseline testing. After two weeks on the Allopurinol, a serum uric acid level was obtained. If the uric acid level was greater than 5.5, the Allopurinol dosage was increased to 600mg (two 300 mg capsules)for the duration of the trial, 6-8 weeks.
Also known as: Zyloprim
Placebo capsule (matched in appearance for Allopurinol and labeled 300mg) was given for 8-10 weeks compared to the Allopurinol group after initial baseline testing. After two weeks on the placebo, a serum uric acid level was obtained. If the uric acid level was greater than 5.5, the placebo dosage was increased to 600mg (two 300 mg capsules)for the duration of the study, 6-8 weeks.
Also known as: sugar pill
Chlorthalidone 25 mg was given daily for 5 weeks before baseline visit for testing and continued through out the study.
Potassium Chloride 40-50meq was given daily for 5 weeks before baseline visit for testing and continued through out the study.
Change in Diastolic Blood Pressure by Cuff 8-10 Weeks Minus Baseline
The Diastolic BP was taken at Baseline and after 8-10 weeks of treatment or placebo while on chlorthalidone and potassium chloride. The blood pressure was measured according to "Shared Care" protocol: 15 minutes of quiet, undisturbed rest with three BP measurements obtained subsequently at 5 minute intervals. The mean of the second and third reading was the value used for analysis for both the Baseline measurement and the measurement after 8 - 10 weeks of treatment. The dependent variable is baseline value minus ending value. Measures are in millimeters of mercury (mm hg)
Time frame: Measured at 8-10 weeks on allopurinol / placebo
Change in Systolic Blood Pressure by Cuff After 8-10 Weeks Minus Baseline
The systolic BP was taken at Baseline and after 8-10 weeks of treatment on placebo, while on chlorthalidone and potassium chloride. The blood pressure was measured according to "Shared Care" protocol: 15 minutes of quiet, undisturbed rest with three BP measurements obtained subsequently at 5 minute intervals. The mean of the second and third reading was the value used for analysis for both the Baseline measurement and the measurement after 8 - 10 weeks of treatment. The dependent variable is baseline value minus ending value. Measures are in millimeters of mercury (mm hg)
Time frame: Measured at 8-10 weeks on allopurinol or placebo
Change in Overall Mean BP From Those Obtained by 24 Hour Ambulatory Blood Pressure Measurements (ABPM) 8-10 Weeks Minus Baseline.
Subjects had 24 hr blood pressure monitoring (ABPM) at baseline and treatment end. The readings were averaged and the changes from baseline to treatment end were compared.
Time frame: Baseline and end of treatment (8-10 weeks on allopurinol / placebo)
Change in Uric Acid (UA) Levels: Baseline Less End of Treatment
Subjects on allopurinol are expected to lower their uric acid levels relative to placebo.
Time frame: Baseline UA levels compared to end of treatment levels (8-10 weeks on allopurinol / placebo)
Recruitment was through flyers and voluntary blood pressure checks and hypertension lectures throughout the county in churches, health fairs, community art festivals, new business openings and celebrations, and in hospital lobbies, business employee lounges, store front spaces at grocery stores and super stores. Individuals also self-refered.
| Milestone | A (Allopurinol) | B(Placebo) |
|---|---|---|
| Started | 71 | 71 |
| Completed | 52 | 53 |
| Not completed | 19 | 18 |
| Withdrew: Withdrawal by subject | 18 | 17 |
| Withdrew: Adverse event | 1 | 1 |
The Diastolic BP was taken at Baseline and after 8-10 weeks of treatment or placebo while on chlorthalidone and potassium chloride. The blood pressure was measured according to "Shared Care" protocol: 15 minutes of quiet, undisturbed rest with three BP measurements obtained subsequently at 5 minute intervals. The mean of the second and third reading was the value used for analysis for both the Baseline measurement and the measurement after 8 - 10 weeks of treatment. The dependent variable is baseline value minus ending value. Measures are in millimeters of mercury (mm hg)
| mm Hg | A (Allopurinol) | B (Placebo) |
|---|---|---|
| Change in Diastolic Blood Pressure by Cuff 8-10 Weeks Minus Baseline | 3.44 ± 12.25 | -0.83 ± 10.63 |
The systolic BP was taken at Baseline and after 8-10 weeks of treatment on placebo, while on chlorthalidone and potassium chloride. The blood pressure was measured according to "Shared Care" protocol: 15 minutes of quiet, undisturbed rest with three BP measurements obtained subsequently at 5 minute intervals. The mean of the second and third reading was the value used for analysis for both the Baseline measurement and the measurement after 8 - 10 weeks of treatment. The dependent variable is baseline value minus ending value. Measures are in millimeters of mercury (mm hg)
| mm Hg | A (Allopurinol) | B (Placebo) |
|---|---|---|
| Change in Systolic Blood Pressure by Cuff After 8-10 Weeks Minus Baseline | 0.21 ± 7.37 | -0.95 ± 8.90 |
Subjects had 24 hr blood pressure monitoring (ABPM) at baseline and treatment end. The readings were averaged and the changes from baseline to treatment end were compared.
| mm Hg | A (Allopurinol) | B (Placebo) |
|---|---|---|
| Change in Overall Mean BP From Those Obtained by 24 Hour Ambulatory Blood Pressure Measurements (ABPM) 8-10 Weeks Minus Baseline. | -5.9 ± 11.9 | 0.90 ± 8.91 |
Subjects on allopurinol are expected to lower their uric acid levels relative to placebo.
| mg/dl | A (Allopurinol) | B (Placebo) |
|---|---|---|
| Change in Uric Acid (UA) Levels: Baseline Less End of Treatment | 2.29 ± 1.29 | 0.14 ± 0.88 |
Collected over Adverse event data were collected for 5 years, 1 month which represents the time the first consent was signed until the last subject completed participation in the study.. Non-serious events are listed at a 5% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| A (Allopurinol) | — | 4/71 (5.6%) | 26/71 (36.6%) |
| B (Placebo) | — | 3/71 (4.2%) | 11/71 (15.5%) |
| Event | A (Allopurinol) | B (Placebo) |
|---|---|---|
| FatigueNervous system disorders | 0/71 | 1/71 |
| Panic AttackNervous system disorders | 1/71 | 0/71 |
| Chest PainCardiac disorders | 1/71 | 0/71 |
| Nausea/VomitingGastrointestinal disorders | 0/71 | 1/71 |
| Car AccidentSocial circumstances | 1/71 | 0/71 |
| SyncopeNervous system disorders | 0/71 | 1/71 |
| RashSkin and subcutaneous tissue disorders | 1/71 | 0/71 |
| Event | A (Allopurinol) | B (Placebo) |
|---|---|---|
| ColdRespiratory, thoracic and mediastinal disorders | 10/71 | 3/71 |
| Musculoskeletal pain/acheMusculoskeletal and connective tissue disorders | 9/71 | 2/71 |
| HeadacheGeneral disorders | 7/71 | 6/71 |
African Americans with borderline high Blood Pressure
| Age, Categorical(Participants) | A (Allopurinol) | B (Placebo) | Total |
|---|---|---|---|
| <=18 years | 0 | 0 | 0 |
| Between 18 and 65 years | 70 | 71 | 141 |
| >=65 years | 1 | 0 | 1 |
| Age Continuous(years) | A (Allopurinol) | B (Placebo) | Total |
|---|---|---|---|
| Mean | 47.7 ± 10.1 | 48.0 ± 7.7 | 47.9 ± 8.8 |
| Sex: Female, Male(Participants) | A (Allopurinol) | B (Placebo) | Total |
|---|---|---|---|
| Female | 51 | 51 | 102 |
| Male | 20 | 20 | 40 |
| Region of Enrollment(participants) | A (Allopurinol) | B (Placebo) | Total |
|---|---|---|---|
| United States | 71 | 71 | 142 |
This study is completed, as verified in Jul 2013. You cannot join it, but the record below documents what was studied.
Get an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
University of Florida