Study of Two Drugs used to Treat Pulmonary Arterial Hypertension

• Research type

  Research Study

• Full title

  AMBITION: A Randomised, Multicenter Study of First-Line Ambrisentan and Tadalafil Combination Therapy in Subjects with Pulmonary Arterial Hypertension

• IRAS ID

  54873

• Contact name

  Andrew J Peacock

• Eudract number

  2009-011150-17

• Clinicaltrials.gov Identifier

  01178073

• Research summary

  Pulmonary arterial hypertension (PAH) is a serious disease affecting the arteries connecting the heart to the lungs (Pulmonary Arteries) and is characterized by a higher-than-normal blood pressure in the pulmonary artery. If left untreated this may lead to heart failure and death within 2-5 years.Combining PAH drugs with different mechanisms of action is becoming more common, as no single drug is effective for all patients. Add-on treatment generally only occurs if initial treatment becomes less effective or if the patients?? PAH becomes worse. It is unknown if patients with PAH may have greater improvement over a longer period of time if they receive combination treatment from the start. This study aims to compare the safety and effectiveness of initial combination therapy (ambrisentan and tadalafil) versus initial mono-therapy (ambrisentan or tadalafil). Ambrisentan is an endothelin receptor antagonist which works by widening the pulmonary arteries, making it easier for the heart to pump blood through them. Tadalafil is a phosphodiesterase 5 inhibitor and works by helping the blood vessels in the lungs to relax. Patients diagnosed with PAH will receive either combination therapy (Ambrisentan and Tadalafil) or mono-therapy (either Ambrisentan and placebo or Tadalafil and placebo) for at least 24 weeks. Neither patients nor their doctors will know which treatment they are receiving. The study will continue until a specified number of patients have experienced a defined worsening of their condition.Patients will see a doctor monthly for blood tests (including a pregnancy test for women who might be able to get pregnant). At weeks 4, 8, 16, 24, and every 12 weeks thereafter, patients will also undergo some other tests, including blood pressure, heart monitoring, tests of how well the lungs are working and a 6-minute walk distance test.

• REC name

  West of Scotland REC 1

• REC reference

  10/S0703/39

• Date of REC Opinion

  11 Aug 2010

• REC opinion

  Further Information Favourable Opinion