A1481244 sildenafil in PAH (2nd)
Research type
Research Study
Full title
A MULTINATIONAL, MULTICENTRE, RANDOMIZED, PARALLEL GROUP, DOUBLE-BLIND STUDY TO ASSESS THE EFFICACY AND SAFETY OF 1 MG, 5MG AND 20 MG TID OF ORAL SILDENAFIL IN THE TREATMENT OF SUBJECTS AGED 18 YEARS AND OVER WITH PULMONARY ARTERIAL HYPERTENSION (PAH)
Sponsor organisation
Pfizer Ltd
Eudract number
2006-006748-76
ISRCTN Number
N/A
Clinicaltrials.gov Identifier
Research summary
Pulmonary Arterial Hypertension(PAH) is a rare condition affecting the lungs in which the blood pressure inthe pulmonary artery (the blood vessel that leads from the heart to the lungs)increases and may become life threatening. Symptoms of PAH include shortness ofbreath, tiredness, chest pain, dizziness, and fainting. Sildenafil (20 mg threetimes a day (tid); RevatioTM) is an oral medicine which has been approved bythe FDA (Food and Drug Administration) and EMEA (European Medicines Agency) foruse in patients with PAH. Sildenafil works by inhibiting PDE-5, a chemicalsubstance found in the body; it helps to relax blood vessels so that bloodflows at the right pressure. We currently do not know the lowest effective doseof sildenafil for PAH, therefore, the effects of three different sildenafildoses, 1, 5 and 20 mg tid, will be studied in order to obtain dose responsedata. This study is divided into two phases. During the treatment phasepatients will be randomly assigned to take sildenafil 1, 5 or 20mg tid for 12weeks. At week 12, all patients will receive Sildenafil 20 mg tid for a further12 week period. This is called the open label phase of the study, since thedoctor and patient know what dose of sildenafil they are taking. Patients whoconsent to take part in the study will be seen as outpatients, and will beasked to attend a clinic 10 times over a maximum period of 32 weeks. Patientsmay undergo up to two Right Heart Catheterization (RHC) procedures depending ontheir recent medical history. This is the standard method used to diagnose PAH.RHC involves a catheter being guided into the patients heart via one of theveins in their arm, leg or neck. This catheter allows pressures in the heart tobe measured accurately. In addition to the RHC patients will be asked tocomplete a ??6 minute walk test?? to see how far they can walk in 6 minutes andmeasure their level of breathlessness during this time. Blood tests,electrocardiograms (ECG) to record the rhythm and electrical activity of thepatients heart, a measurement of right heart function using echocardiography,blood pressure and pulse measurements and a physical examination will also becarried out. A lung function test to measure total lung capacity may be done insome patients.
REC name
South West - Cornwall & Plymouth Research Ethics Committee
REC reference
08/H0206/56
Date of REC Opinion
14 Oct 2008
REC opinion
Further Information Favourable Opinion