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Effect of Regular Sildenafil on Blood Pressure and Arterial Function in Hypertension

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: NCT00317421
Recruitment Status : Completed
First Posted : April 24, 2006
Last Update Posted : April 24, 2006
Information provided by:
University of Edinburgh

Tracking Information
First Submitted Date  ICMJE April 20, 2006
First Posted Date  ICMJE April 24, 2006
Last Update Posted Date April 24, 2006
Study Start Date  ICMJE March 2004
Primary Completion Date Not Provided
Current Primary Outcome Measures  ICMJE
 (submitted: April 20, 2006)
  • Change in blood pressure
  • Change in flow-mediated dilatation
  • Change in central augmentation index (derived from pulse wave analysis)
  • Change in carotid-femoral pulse wave velocity
Original Primary Outcome Measures  ICMJE Same as current
Change History No Changes Posted
Current Secondary Outcome Measures  ICMJE Not Provided
Original Secondary Outcome Measures  ICMJE Not Provided
Current Other Pre-specified Outcome Measures Not Provided
Original Other Pre-specified Outcome Measures Not Provided
Descriptive Information
Brief Title  ICMJE Effect of Regular Sildenafil on Blood Pressure and Arterial Function in Hypertension
Official Title  ICMJE Effects of Regular Treatment With Sildenafil on Blood Pressure and Endothelial Function in Untreated Hypertensives
Brief Summary The purpose of the study is to investigate if regular treatment with sildenafil reduces blood pressure and improves blood vessel function in patients with hypertension (high blood pressure).
Detailed Description

Inhibitors of phosphodiesterase type 5 (PDE5), such as sildenafil, relax blood vessels. In the penis this facilitates erection and sildenafil has proved a very effective treatment for male erectile dysfunction.

To date, most work on the effects of sildenafil on blood pressure have mainly been investigated in single dose studies. These have shown that sildenafil causes a modest reduction in blood pressure, even when taken with other blood pressure-lowering drugs, providing reassurance on safety when taken as a single dose for erectile dysfunction. However, these studies do not offer any insight into the potential of PDE5 inhibition in the long-term treatment of hypertension. We will address this question by investigating the effects of regular administration of sildenafil on blood pressure. It may also be postulated that, because of its mechanism of action, sildenafil will also improve the function of the endothelium, the single layer of cells that lines all blood vessels. Therefore, the effect of regular sildenafil on endothelial function in hypertension will also be investigated in the study.

The study will be performed in a randomised, placebo-controlled, double blind, 2-way crossover manner. Sildenafil and matched placebo will each will taken three times daily for 2 weeks, with a washout of at least 6 days between treatments. Measurements will be made acutely (before and 1 hour after oral sildenafil) of heart rate, blood pressure, pulse wave analysis (a measure of wave reflection in arteries), pulse wave velocity (a measure of arterial stiffness) and flow-mediated dilatation (a measure of endothelial function). These measurements will be repeated 2 weeks later (again just before and 1 hour after oral sildenafil). In addition, ambulatory blood pressure will be recorded after 2 weeks of treatment (baseline ambulatory BP will be taken as the recording made at diagnosis).

Study Type  ICMJE Interventional
Study Phase  ICMJE Phase 2
Study Design  ICMJE Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Double
Primary Purpose: Treatment
Condition  ICMJE Hypertension
Intervention  ICMJE Drug: Sildenafil citrate
Study Arms  ICMJE Not Provided
Publications * Zusman RM, Morales A, Glasser DB, Osterloh IH. Overall cardiovascular profile of sildenafil citrate. Am J Cardiol. 1999 Mar 4;83(5A):35C-44C. Review.

*   Includes publications given by the data provider as well as publications identified by Identifier (NCT Number) in Medline.
Recruitment Information
Recruitment Status  ICMJE Completed
Enrollment  ICMJE
 (submitted: April 20, 2006)
Original Enrollment  ICMJE Same as current
Study Completion Date  ICMJE November 2005
Primary Completion Date Not Provided
Eligibility Criteria  ICMJE

Inclusion Criteria:

  • Male or female
  • Hypertensive (office systolic BP ≥160 mmHg or diastolic BP ≥100 mmHg), not taking antihypertensive drugs OR hypertensive controlled (systolic BP < 160 mmHg or diastolic BP < 100 mmHg) on 1 antihypertensive agent
  • Hypertension confirmed on ambulatory monitoring (average daytime BP ≥145/95 mmHg)
  • Patients will also be included if they have ‘borderline’ hypertension and their calculated 10-year risk of cardiovascular disease is >20% or they have target organ damage. Borderline hypertension will be defined according to ambulatory BP criteria alone (average awake systolic BP ≥135 and <145 mmHg or diastolic BP ≥85 and <95 mmHg).

Exclusion Criteria:

  • History of other major cardiac, respiratory, neurological or renal disease
  • Systolic BP consistently >210 mmHg or diastolic BP consistently >120 mmHg
  • Systolic BP consistently >180 mmHg or diastolic BP consistently >110 mmHg in those withdrawn from existing therapy
  • Current alcohol abuse
  • Diabetes
  • Taking vasoactive drugs
  • Previous serious drug allergy
  • Pregnant
  • Participation, within 6 months, in other research studies
Sex/Gender  ICMJE
Sexes Eligible for Study: All
Ages  ICMJE Child, Adult, Older Adult
Accepts Healthy Volunteers  ICMJE No
Contacts  ICMJE Contact information is only displayed when the study is recruiting subjects
Listed Location Countries  ICMJE United Kingdom
Removed Location Countries  
Administrative Information
NCT Number  ICMJE NCT00317421
Other Study ID Numbers  ICMJE JO-02
Has Data Monitoring Committee Not Provided
U.S. FDA-regulated Product Not Provided
IPD Sharing Statement  ICMJE Not Provided
Responsible Party Not Provided
Study Sponsor  ICMJE University of Edinburgh
Collaborators  ICMJE Pfizer
Investigators  ICMJE
Principal Investigator: James J Oliver, MBChB University of Edinburgh
PRS Account University of Edinburgh
Verification Date February 2004

ICMJE     Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP