Phase 2 Extension Study of Ambrisentan in Pulmonary Arterial Hypertension

• ClinicalTrials.gov Identifier: NCT00424021
• Recruitment Status: Completed
• First Posted: January 18, 2007
• Results First Posted: January 27, 2012
• Last Update Posted: January 27, 2012
• Sponsor: Gilead Sciences
• Information provided by (Responsible Party): Gilead Sciences

Study Description

Brief Summary:

AMB-220-E is an international, multicenter, open-label study examining the long-term safety of ambrisentan (BSF 208075) in subjects who have previously completed Myogen study NCT00046319, "A Phase II, Randomized, Double-Blind, Dose-Controlled, Dose-Ranging, Multicenter Study of BSF 208075 Evaluating Exercise Capacity in Subjects with Moderate to Severe Pulmonary Arterial Hypertension".

Condition or disease	Intervention/treatment	Phase
Pulmonary Hypertension	Drug: ambrisentan	Phase 2

Study Design

• Study Type: Interventional (Clinical Trial)
• Actual Enrollment: 54 participants
• Allocation: Non-Randomized
• Intervention Model: Single Group Assignment
• Masking: None (Open Label)
• Primary Purpose: Treatment
• Official Title: An Open-Label, Long-Term Study of Ambrisentan in Pulmonary Hypertension Subjects Having Completed Myogen Study AMB-220
• Study Start Date: April 2003
• Actual Primary Completion Date: December 2009
• Actual Study Completion Date: December 2009

Arms and Interventions

Intervention Details:

• Drug: ambrisentan
  1, 2.5, 5, and 10 mg ambrisentan given orally once daily
  Other Names:

  • BSF 208075
  • Letairis
  • Volibris

Outcome Measures

Primary Outcome Measures :

1. Number of Participants With Pulmonary Arterial Hypertension (PAH) Who Completed the Phase II NCT00046319 Study and Who Experienced Severe Adverse Events (AEs) During Long-term Ambrisentan Exposure [ Time Frame: Week 24 (AMB-220-E baseline) to Week 334 ]
   The number of participants in the AMB-220-E analysis set who experienced AEs (including serious AEs) of severe severity (ie, made it impossible to perform routine activities and the subject may have experienced intolerable discomfort or pain) that began after entering AMB-220-E (treatment-emergent AEs) and that occurred in more than 1 participant are summarized by dose group. The AMB-220-E analysis set consisted of all participants who received at least 1 dose of study drug during the AMB-220-E study.
2. Number of Participants With PAH Who Completed the Phase II NCT00046319 Study and Who Experienced AEs of Moderate Severity During Long-term Ambrisentan Exposure [ Time Frame: Week 24 (AMB-220-E baseline) to Week 329.3 ]
   The number of participants in the AMB-220-E analysis set who experienced AEs (including serious AEs) of moderate severity (ie, interfered with routine activities and subject may have experienced significant discomfort) that began after entering AMB-220-E (treatment-emergent AEs) and that occurred in more than 1 participant are summarized by dose group. The AMB-220-E analysis set consisted of all participants who received at least 1 dose of study drug during the AMB-220-E study.
3. Number of Participants With PAH Who Completed the Phase II NCT00046319 Study and Who Experienced AEs of Mild Severity During Long-term Ambrisentan Exposure [ Time Frame: Week 24 (AMB-220-E baseline) to Week 329.3 ]
   The number of participants in the AMB-220-E analysis set who experienced AEs (including serious AEs) of mild severity (ie, did not interfere with routine activities and the subject may have experienced slight discomfort) that began after entering AMB-220-E (treatment-emergent AEs) and that occurred in more than 1 participant are summarized by dose group. The AMB-220-E analysis set consisted of all participants who received at least 1 dose of study drug during the AMB-220-E study.

Secondary Outcome Measures :

1. Baseline Measurement in Exercise Capacity as Measured by the 6-minute Walk Test (6MWT) Distance (Baseline [Week 24]) [ Time Frame: Week 24 (AMB-220-E baseline) ]
   The 6MWT was conducted according to the American Thoracic Society guidelines (ATS statement: guidelines for the six-minute walk test. Am J Respir Crit Care Med 2002; 166(1):111-117.) Primary efficacy analyses were performed for the AMB-220-E analysis set (all subjects who received at least 1 dose of study drug during the AMB-220-E study).
2. Change From Baseline (Week 24 of NCT00046319) in Exercise Capacity as Measured by the 6-minute Walk Test (6MWT) Distance (Last Observation Carried Forward [LOCF]) (Week 48) [ Time Frame: 24 weeks (Week 24 to Week 48) ]
   The 6MWT was conducted according to the American Thoracic Society guidelines (ATS statement: guidelines for the six-minute walk test. Am J Respir Crit Care Med 2002; 166(1):111-117.) Primary efficacy analyses were performed for the AMB-220-E analysis set (all subjects who received at least 1 dose of study drug during the AMB-220-E study).
3. Change From Baseline (Week 24 of NCT00046319) in Exercise Capacity as Measured by the 6-minute Walk Test (6MWT) Distance (LOCF) (Week 108) [ Time Frame: 84 weeks (Week 24 to Week 108) ]
   The 6MWT was conducted according to the American Thoracic Society guidelines (ATS statement: guidelines for the six-minute walk test. Am J Respir Crit Care Med 2002; 166(1):111-117.) Primary efficacy analyses were performed for the AMB-220-E analysis set (all subjects who received at least 1 dose of study drug during the AMB-220-E study).
4. Change From Baseline (Week 24 of NCT00046319) in Exercise Capacity as Measured by the 6-minute Walk Test (6MWT) Distance (LOCF) (Week 156) [ Time Frame: 132 weeks (Week 24 to Week 156) ]
   The 6MWT was conducted according to the American Thoracic Society guidelines (ATS statement: guidelines for the six-minute walk test. Am J Respir Crit Care Med 2002; 166(1):111-117.) Primary efficacy analyses were performed for the AMB-220-E analysis set (all subjects who received at least 1 dose of study drug during the AMB-220-E study).
5. Change From Baseline (Week 24 of NCT00046319) in Exercise Capacity as Measured by the 6-minute Walk Test (6MWT) Distance (LOCF) (Week 204) [ Time Frame: 180 weeks (Week 24 to Week 204) ]
   The 6MWT was conducted according to the American Thoracic Society guidelines (ATS statement: guidelines for the six-minute walk test. Am J Respir Crit Care Med 2002; 166(1):111-117.) Primary efficacy analyses were performed for the AMB-220-E analysis set (all subjects who received at least 1 dose of study drug during the AMB-220-E study).
6. Baseline Measurement in Exercise Capacity as Measured by the Borg Dyspnea Index (BDI) (Baseline [Week 24]) [ Time Frame: Week 24 (AMB-220-E baseline) ]
   Change from baseline evaluated after 24 (baseline), 48, 108, 156, and 204 weeks of ambrisentan therapy in BDI (measured as units on a scale) immediately following exercise. Borg Dyspnea Index, a measure of perceived shortness of breath: 0 units on a scale (none) to 10 units on a scale (maximum breathlessness).
7. Change From Baseline (Week 24 of NCT00046319) in Exercise Capacity as Measured by the BDI (LOCF) (Week 48) [ Time Frame: 24 weeks (Week 24 to Week 48) ]
   Change from baseline evaluated after 24 (baseline), 48, 108, 156, and 204 weeks of ambrisentan therapy in BDI (measured as units on a scale) immediately following exercise. Borg Dyspnea Index, a measure of perceived shortness of breath: 0 units on a scale (none) to 10 units on a scale (maximum breathlessness).
8. Change From Baseline (Week 24 of NCT00046319) in Exercise Capacity as Measured by the BDI (LOCF) (Week 108) [ Time Frame: 84 weeks (Week 24 to Week 108) ]
   Change from baseline evaluated after 24 (baseline), 48, 108, 156, and 204 weeks of ambrisentan therapy in BDI (measured as units on a scale) immediately following exercise. Borg Dyspnea Index, a measure of perceived shortness of breath: 0 units on a scale (none) to 10 units on a scale (maximum breathlessness).
9. Change From Baseline (Week 24 of NCT00046319) in Exercise Capacity as Measured by the BDI (LOCF) (Week 156) [ Time Frame: 132 weeks (Week 24 to Week 156) ]
   Change from baseline evaluated after 24 (baseline), 48, 108, 156, and 204 weeks of ambrisentan therapy in BDI (measured as units on a scale) immediately following exercise. Borg Dyspnea Index, a measure of perceived shortness of breath: 0 units on a scale (none) to 10 units on a scale (maximum breathlessness).
10. Change From Baseline (Week 24 of NCT00046319) in Exercise Capacity as Measured by the BDI (LOCF) (Week 204) [ Time Frame: 180 weeks (Week 24 to Week 204) ]
    Change from baseline evaluated after 24 (baseline), 48, 108, 156, and 204 weeks of ambrisentan therapy in BDI (measured as units on a scale) immediately following exercise. Borg Dyspnea Index, a measure of perceived shortness of breath: 0 units on a scale (none) to 10 units on a scale (maximum breathlessness).
11. Baseline Measurement in Exercise Capacity as Measured by the World Health Organization (WHO) Functional Classification (Baseline [Week 24]) [ Time Frame: Week 24 (AMB-220-E baseline) ]
    Classes: I) pulmonary hypertension (PH); ordinary physical activity not limited or causes increased dyspnea, fatigue, chest pain, or presyncope. II) PH; ordinary physical activity mildly limited and causes increased dyspnea, fatigue, chest pain, or presyncope; comfortable at rest. III) PH; physical activity markedly limited and less than ordinary physical activity causes increased dyspnea, fatigue, chest pain, or presyncope; comfortable at rest. IV) PH; physical activity causes symptoms; signs of right heart failure; dyspnea/fatigue possibly at rest.
12. Exercise Capacity as Measured by the WHO Functional Classification (LOCF) After 24 Weeks of Treatment in AMB-220-E [ Time Frame: 24 weeks (Week 24 [baseline of AMB-220-E] to Week 48) ]
    Classes: I) PH; ordinary physical activity not limited or causes increased dyspnea, fatigue, chest pain, or presyncope. II) PH; ordinary physical activity mildly limited and causes increased dyspnea, fatigue, chest pain, or presyncope; comfortable at rest. III) PH; physical activity markedly limited and less than ordinary physical activity causes increased dyspnea, fatigue, chest pain, or presyncope; comfortable at rest. IV) PH; physical activity causes symptoms; signs of right heart failure; dyspnea/fatigue possibly at rest.
13. Exercise Capacity as Measured by the WHO Functional Classification (LOCF) After 84 Weeks of Treatment in AMB-220-E [ Time Frame: 84 weeks (Week 24 of NCT00046319 to Week 108) ]
    Classes: I) PH; ordinary physical activity not limited or causes increased dyspnea, fatigue, chest pain, or presyncope. II) PH; ordinary physical activity mildly limited and causes increased dyspnea, fatigue, chest pain, or presyncope; comfortable at rest. III) PH; physical activity markedly limited and less than ordinary physical activity causes increased dyspnea, fatigue, chest pain, or presyncope; comfortable at rest. IV) PH; physical activity causes symptoms; signs of right heart failure; dyspnea/fatigue possibly at rest.
14. Exercise Capacity as Measured by the WHO Functional Classification (LOCF) After 132 Weeks of Treatment in AMB-220-E [ Time Frame: 132 weeks (Week 24 of NCT00046319 to Week 156) ]
    Classes: I) PH; ordinary physical activity not limited or causes increased dyspnea, fatigue, chest pain, or presyncope. II) PH; ordinary physical activity mildly limited and causes increased dyspnea, fatigue, chest pain, or presyncope; comfortable at rest. III) PH; physical activity markedly limited and less than ordinary physical activity causes increased dyspnea, fatigue, chest pain, or presyncope; comfortable at rest. IV) PH; physical activity causes symptoms; signs of right heart failure; dyspnea/fatigue possibly at rest.
15. Exercise Capacity as Measured by the WHO Functional Classification (LOCF) After 180 Weeks of Treatment in AMB-220-E [ Time Frame: 180 weeks (Week 24 of NCT00046319 to Week 204) ]
    Classes: I) PH; ordinary physical activity not limited or causes increased dyspnea, fatigue, chest pain, or presyncope. II) PH; ordinary physical activity mildly limited and causes increased dyspnea, fatigue, chest pain, or presyncope; comfortable at rest. III) PH; physical activity markedly limited and less than ordinary physical activity causes increased dyspnea, fatigue, chest pain, or presyncope; comfortable at rest. IV) PH; physical activity causes symptoms; signs of right heart failure; dyspnea/fatigue possibly at rest.
16. Baseline Measurement in Exercise Capacity as Measured by the Subject Global Assessment (SGA) (Baseline [Week 24]) [ Time Frame: Week 24 (AMB-220-E baseline) ]
    The SGA was determined using a visual-analog scale. Subjects were asked the question, "How are you feeling today?" and were asked to draw a vertical mark on a 100-mm horizontal line in which zero represented "very poor" and 100 represented "excellent."
17. Change From Baseline (Week 24 of NCT00046319) in Exercise Capacity as Measured by the SGA (LOCF) (Week 48) [ Time Frame: 24 weeks (Week 24 to Week 48) ]
    The SGA was determined using a visual-analog scale. Subjects were asked the question, "How are you feeling today?" and were asked to draw a vertical mark on a 100-mm horizontal line in which zero represented "very poor" and 100 represented "excellent."
18. Change From Baseline (Week 24 of NCT00046319) in Exercise Capacity as Measured by the SGA (LOCF) (Week 108) [ Time Frame: 84 weeks (Week 24 to Week 108) ]
    The SGA was determined using a visual-analog scale. Subjects were asked the question, "How are you feeling today?" and were asked to draw a vertical mark on a 100-mm horizontal line in which zero represented "very poor" and 100 represented "excellent."
19. Change From Baseline (Week 24 of NCT00046319) in Exercise Capacity as Measured by the SGA (LOCF) (Week 156) [ Time Frame: 132 weeks (Week 24 to Week 156) ]
    The SGA was determined using a visual-analog scale. Subjects were asked the question, "How are you feeling today?" and were asked to draw a vertical mark on a 100-mm horizontal line in which zero represented "very poor" and 100 represented "excellent."
20. Change From Baseline (Week 24 of NCT00046319) in Exercise Capacity as Measured by the SGA (LOCF) (Week 204) [ Time Frame: 180 weeks (Week 24 to Week 204) ]
    The SGA was determined using a visual-analog scale. Subjects were asked the question, "How are you feeling today?" and were asked to draw a vertical mark on a 100-mm horizontal line in which zero represented "very poor" and 100 represented "excellent."
21. Time to Clinical Worsening of PAH [ Time Frame: Week 0 (NCT00046319 baseline) to Week 360 ]
    Clinical worsening of PAH was defined as death, lung transplantation, hospitalization for PAH, atrial septostomy, the addition of approved prostanoid therapy, or study withdrawal due to the addition of other clinically approved PAH therapeutic agents. Sildenafil, a type 5 phosphodiesterase (PDE-5) inhibitor, had not received regulatory approval for the treatment of PAH until late in the conduct of AMB 220 and AMB 220-E, and did not count toward clinical worsening. Results are presented as the Kaplan-Meier estimate (% probability) of not having clinical worsening after a given time.
22. Failure-free Treatment Status [ Time Frame: Week 0 (NCT00046319 baseline) to Week 360 ]
    Failure-free treatment status was defined as the time from initiation of active treatment to the first occurrence of death, lung transplantation, the addition of approved prostanoid therapy, or study withdrawal due to the addition of other clinically approved PAH therapeutic agents. Results are presented as the Kaplan-Meier estimate (% probability) of not having treatment failure after a given time.
23. Long-term Survival [ Time Frame: Week 24 (AMB-220-E baseline) to Week 329.3 ]
    Long-term survival was defined as the time from initiation of active treatment to death. Results are presented as the Kaplan-Meier estimate (% probability) of survival after a given time.

Eligibility Criteria

• Ages Eligible for Study: 18 Years and older (Adult, Older Adult)
• Sexes Eligible for Study: All
• Accepts Healthy Volunteers: No

Criteria

Inclusion Criteria:

• Must have completed Visit 14/Week 24 of the NCT00046319 study.
• Women of childbearing potential must have a negative urine pregnancy test at the Screening/Enrollment Visit and agree to use a reliable double barrier method of contraception until study completion and for >=4 weeks following their final study visit.
• Must have completed the Down-titration Period of NCT00046319 prior to enrollment in AMB-220-E and will meet the following additional criteria:
• Subjects with a diagnosis of HIV must have stable disease status at the time of Screening/Enrollment.
• Must be stable on conventional therapy for PAH for >=4 weeks prior to the Screening Visit.

Exclusion Criteria:

• Chronic prostanoid therapy, or other investigational prostacyclin derivative within 4 weeks prior to the Screening Visit.
• Intravenous inotrope use within 2 weeks prior to the Screening Visit.
• Females who are pregnant or breastfeeding.
• Contraindication to treatment with an endothelin receptor antagonist (ERA).

Contacts and Locations

No Contacts or Locations Provided

More Information

Additional Information:

Pulmonary Hypertension Association 

• Responsible Party: Gilead Sciences
• ClinicalTrials.gov Identifier: NCT00424021
• Other Study ID Numbers: AMB-220-E
• First Posted: January 18, 2007
• Results First Posted: January 27, 2012
• Last Update Posted: January 27, 2012
• Last Verified: December 2011

Additional relevant MeSH terms:

Hypertension, Pulmonary; Hypertension; Vascular Diseases; Cardiovascular Diseases; Lung Diseases; Respiratory Tract Diseases; Ambrisentan; Antihypertensive Agents