Effect of Regular Sildenafil on Blood Pressure and Arterial Function in Hypertension - Full Text View

Sponsors and Collaborators:	University of Edinburgh Pfizer
Information provided by:	University of Edinburgh
ClinicalTrials.gov Identifier:	NCT00317421

Purpose

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).

Condition	Intervention	Phase
Hypertension	Drug: Sildenafil citrate	Phase II

MedlinePlus related topics: High Blood Pressure

Drug Information available for: Sildenafil citrate Sildenafil Citric acid Sodium Citrate

U.S. FDA Resources

Study Type:	Interventional
Study Design:	Treatment, Randomized, Double-Blind, Placebo Control, Crossover Assignment, Efficacy Study
Official Title:	Effects of Regular Treatment With Sildenafil on Blood Pressure and Endothelial Function in Untreated Hypertensives

Further study details as provided by University of Edinburgh:

Primary Outcome Measures:

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

Estimated Enrollment:	20
Study Start Date:	March 2004
Estimated Study Completion Date:	November 2005

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).

Eligibility

Genders Eligible for Study:	Both
Accepts Healthy Volunteers:	No

Criteria

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

Contacts and Locations

Please refer to this study by its ClinicalTrials.gov identifier: NCT00317421

Locations

United Kingdom, Lothian
Clinical Pharmacology Unit, University of Edinburgh
Edinburgh, Lothian, United Kingdom, EH4 2XU

Sponsors and Collaborators

University of Edinburgh

Pfizer

Investigators

Principal Investigator:

James J Oliver, MBChB

University of Edinburgh

More Information

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.

Study ID Numbers:	JO-02
Study First Received:	April 20, 2006
Last Updated:	April 20, 2006
ClinicalTrials.gov Identifier:	NCT00317421
Health Authority:	Scotland: local Research Ethics Committee

Keywords provided by University of Edinburgh:

Phosphodiesterase 5
Sildenafil
Hypertension

Blood pressure
Arterial stiffness
Endothelial function

Study placed in the following topic categories:

Citric Acid
Vascular Diseases
Sildenafil
Hypertension

Additional relevant MeSH terms:

Vasodilator Agents
Phosphodiesterase Inhibitors
Molecular Mechanisms of Pharmacological Action
Therapeutic Uses

Enzyme Inhibitors
Cardiovascular Diseases
Cardiovascular Agents
Pharmacologic Actions

ClinicalTrials.gov processed this record on January 16, 2009