A Study of First-Line Ambrisentan and Tadalafil Combination Therapy in Subjects With Pulmonary Arterial Hypertension (PAH) (AMBITION)

• ClinicalTrials.gov Identifier: NCT01178073
• Recruitment Status: Completed
• First Posted: August 9, 2010
• Results First Posted: April 28, 2015
• Last Update Posted: September 13, 2017
• Sponsor: GlaxoSmithKline
• Collaborator: Gilead Sciences
• Information provided by (Responsible Party): GlaxoSmithKline

Tracking Information

• First Submitted Date: July 15, 2010
• First Posted Date: August 9, 2010
• Results First Submitted Date: March 23, 2015
• Results First Posted Date: April 28, 2015
• Last Update Posted Date: September 13, 2017
• Study Start Date: October 1, 2010
• Actual Primary Completion Date: July 31, 2014 (Final data collection date for primary outcome measure)

Current Primary Outcome Measures (submitted: April 9, 2015)

Number of Participants With First Adjudicated Clinical Failure (CF) Event, Death, Hospitalisation for Worsening PAH, Disease Progression, Unsatisfactory Long-term Clinical Response, All Through FAV [ Time Frame: From Baseline up to the Final Assessment Visit (FAV) (average of 609 days) ]

Time to the first adjudicated CF event (death, hospitalization for worsening pulmonary arterial hypertension [PAH], disease progression, or unsatisfactory long-term clinical response) after initiating either first-line combination therapy with AMB and TAD or first-line monotherapy with either drug (AMB or TAD) in par. with PAH was assessed. If data was not available for some par. following a loss to follow-up, their event times were treated as censored at their last assessment time for the statistical analyses. FAV occurred approximately 4 weeks after the predicted 105th adjudicated first CF event was reached. Par. who had an FAV, and who had no adjudicated events or whose first adjudicated event occurred after their FAV, were censored at their individual FAV. Modified Intent-to-Treat (mITT) Population: all randomized par. who met the PAH diagnosis and inclusion/exclusion criteria defined in protocol amendment 2 and who also received at least one dose of investigational product (IP).

• Original Primary Outcome Measures (submitted: August 6, 2010): Time to Clinical Failure [ Time Frame: The study will be terminated when it is projected that approximately 82 events have occurred. Based on current assumptions, the median treatment duration is anticipated to be 1.6 years with the total study duration estimated at 2.5 years. ]

Current Secondary Outcome Measures (submitted: April 9, 2015)

• Percent Change From Baseline in the N-Terminal Pro-B-Type Natriuretic Peptide at Week 24 [ Time Frame: Baseline and Week 24 ]
  N-Terminal Pro-B-Type Natriuretic Peptide (NT-proBNP) is a surrogate marker of heart failure. The data were log-transformed. The geometric mean was calculated (based on the log-transformed data). The geometric mean ratio was calculated as the ratio between the Week 24 value and the Baseline value (based on the log-transformed data) and presented as percent change = 100 * (geometric mean ratio - 1). The Baseline value is the last value prior to administration of study drug; this may be prior to or on the day of study drug initiation. No imputation was performed for missing data. The secondary endpoints were analyzed according to a pre-specified hierarchical testing procedure.
• Percentage of Participants With a Satisfactory Clinical Response at Week 24 [ Time Frame: Baseline and Week 24 ]
  A satisfactory clinical response at Week 24 is defined as a participant who meets all of the following criteria: 10% improvement in 6MWD compared with Baseline; improvement to or maintenance of World Health Organization (WHO) class I or II symptoms; no events of clinical worsening prior to or at the Week 24 visit. Clinical worsening events included: death, hospitalization for pulmonary arterial hypertension (PAH), and disease progression. Participants without an event of clinical worsening prior to or at the Week 24 visit who did not have a 6MWD value or a WHO functional class value at Week 24 were excluded from the analysis.
• Change From Baseline in the 6 Minute Walk Distance Test at Week 24 [ Time Frame: Baseline and Week 24 ]
  The 6-minute walk distance (6MWD) test measures the distance that a participant can walk in a period of 6 minutes. Change from Baseline was calculated as the Week 24 value minus the Baseline value. The analysis was performed based on last observation carried forward data, except in the case of an adjudicated clinical failure event of death or hospitalization preceding the missing data observation. In this case, the missing observation was assigned the worst-rank score relative to those actually observed and was assigned a rank reflecting the relative order of the actual event times. Baseline 6MWD comprised of an average of the last two consecutive measurements prior to randomization that varied by no greater than 10%. If only one measurement was available, that measurement was used. If no two consecutive measures vary by no greater than 10% then Baseline was based on the last two consecutive measures for a participant.
• Change From Baseline in the World Health Organization Functional Class at Week 24 [ Time Frame: Baseline and Week 24 ]
  The WHO Functional Class (FC) indicates the severity of PAH and is an adaptation of the New York Heart Association classification. It was assessed by the investigator. There are four grades for WHO FC based on severity of symptoms (Class I = none, Class IV = most severe). Baseline WHO FC is the latest assessment prior to dosing (i.e., at Randomization or Screening). Change from Baseline at Week 24 was calculated as the Week 24 value minus the Baseline value. The analysis was performed based on the last observation carried forward data, except in the case of an adjudicated clinical failure event of death or hospitalization preceding the missing data observation. In this case, the missing observations was assigned the worst-rank score relative to those actually observed and was assigned rank reflecting the relative order of the actual event times.
• Change From Baseline in Borg Dyspnea Index at Week 24 [ Time Frame: Baseline (BL) and Week 24 ]
  Borg Dyspnea Index (BDI) indicates the degree of breathlessness after completion of the 6 minute walk test. The BDI was calculated by using the Borg category (C) ratio (R) CR10 scale which starts at 0 (nothing at all) and has no upper limit (extremely strong). Change from BL was calculated as the Week 24 values minus the BL value. The BDI scale was assessed by each participant. The BL BDI score is the average of the two BDI values obtained following the two 6MWD tests used in determining the BL 6MWD. A negative change from BL in the BDI score represented an improvement for the participant. The analysis was performed based on the last observation carried forward data, except in the case of an adjudicated clinical failure event of death or hospitalization preceding the missing data observation. In this case, the missing observation was assigned the worst-rank score relative to those actually observed and was assigned rank reflecting the relative order of the actual event times.

Original Secondary Outcome Measures (submitted: August 6, 2010)

• 6 minute Walk Distance test [ Time Frame: Change from baseline to Week 24 ]
• Percentage of subjects with unsatisfactory clinical response [ Time Frame: Week 24 ]
• N-terminal pro-B-type natriuretic peptide (NT-Pro BNP) [ Time Frame: Change from baseline to Week 24 ]
• World Health Organisation (WHO) Functional Class [ Time Frame: Change from baseline to Week 24 ]
• Borg Dyspnea Index [ Time Frame: Change from baseline to Week 24 ]

• Current Other Pre-specified Outcome Measures: Not Provided
• Original Other Pre-specified Outcome Measures: Not Provided

Descriptive Information

• Brief Title: A Study of First-Line Ambrisentan and Tadalafil Combination Therapy in Subjects With Pulmonary Arterial Hypertension (PAH)
• Official Title: AMBITION: A Randomised, Multicenter Study of First-Line Ambrisentan and Tadalafil Combination Therapy in Subjects With Pulmonary Arterial Hypertension (PAH)
• Brief Summary: The purpose of this study is to compare the two treatment strategies; first-line combination therapy (ambrisentan and tadalafil) versus first-line monotherapy (ambrisentan or tadalafil) in subjects with Pulmonary Arterial Hypertension. This will be assessed by time to the first clinical failure event.
• Detailed Description: Not Provided
• Study Type: Interventional
• Study Phase: Phase 3
• Study Design: Allocation: Randomized; Intervention Model: Parallel Assignment; Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor); Primary Purpose: Treatment
• Condition: Hypertension, Pulmonary

Intervention

• Drug: ambrisentan
  ambrisentan (target dose: 10mg)
• Drug: tadalafil
  tadalafil (target dose: 40mg)

Study Arms

• Active Comparator: Combination ambrisentan + tadalafil
  ambrisentan + tadalafil
  Interventions:

  • Drug: ambrisentan
  • Drug: tadalafil
• Active Comparator: Monotherapy ambrisentan
  ambrisentan
  Intervention: Drug: ambrisentan
• Active Comparator: Monotherapy tadalafil
  tadalafil
  Intervention: Drug: tadalafil

Publications *

• Kuwana M, Blair C, Takahashi T, Langley J, Coghlan JG. Initial combination therapy of ambrisentan and tadalafil in connective tissue disease-associated pulmonary arterial hypertension (CTD-PAH) in the modified intention-to-treat population of the AMBITION study: post hoc analysis. Ann Rheum Dis. 2020 May;79(5):626-634. doi: 10.1136/annrheumdis-2019-216274. Epub 2020 Mar 11. Erratum In: Ann Rheum Dis. 2020 Sep;79(9):e118.
• White RJ, Vonk-Noordegraaf A, Rosenkranz S, Oudiz RJ, McLaughlin VV, Hoeper MM, Grunig E, Ghofrani HA, Chakinala MM, Barbera JA, Blair C, Langley J, Frost AE. Clinical outcomes stratified by baseline functional class after initial combination therapy for pulmonary arterial hypertension. Respir Res. 2019 Sep 12;20(1):208. doi: 10.1186/s12931-019-1180-1.
• Coghlan JG, Galie N, Barbera JA, Frost AE, Ghofrani HA, Hoeper MM, Kuwana M, McLaughlin VV, Peacock AJ, Simonneau G, Vachiery JL, Blair C, Gillies H, Miller KL, Harris JHN, Langley J, Rubin LJ; AMBITION investigators. Initial combination therapy with ambrisentan and tadalafil in connective tissue disease-associated pulmonary arterial hypertension (CTD-PAH): subgroup analysis from the AMBITION trial. Ann Rheum Dis. 2017 Jul;76(7):1219-1227. doi: 10.1136/annrheumdis-2016-210236. Epub 2016 Dec 30.
• Galie N, Barbera JA, Frost AE, Ghofrani HA, Hoeper MM, McLaughlin VV, Peacock AJ, Simonneau G, Vachiery JL, Grunig E, Oudiz RJ, Vonk-Noordegraaf A, White RJ, Blair C, Gillies H, Miller KL, Harris JH, Langley J, Rubin LJ; AMBITION Investigators. Initial Use of Ambrisentan plus Tadalafil in Pulmonary Arterial Hypertension. N Engl J Med. 2015 Aug 27;373(9):834-44. doi: 10.1056/NEJMoa1413687.
• Peacock AJ, Zamboni W, Vizza CD. Ambrisentan for the treatment of adults with pulmonary arterial hypertension: a review. Curr Med Res Opin. 2015;31(9):1793-807. doi: 10.1185/03007995.2015.1074890. Epub 2015 Aug 27.

Recruitment Information

• Recruitment Status: Completed
• Actual Enrollment (submitted: September 25, 2014): 610
• Original Enrollment (submitted: August 6, 2010): 300
• Actual Study Completion Date: July 31, 2014
• Actual Primary Completion Date: July 31, 2014 (Final data collection date for primary outcome measure)

Eligibility Criteria

Inclusion Criteria:

• Subjects must have a diagnosis of Pulmonary Arterial Hypertension (PAH) due to the following:

  a. idiopathic or heritable PAH b. PAH associated with: i. connective tissue disease (e.g., limited scleroderma, diffuse scleroderma, mixed connective tissue disease, systemic lupus erythematosus, or overlap syndrome) ii. drugs or toxins iii. Human Immunodeficiency Virus (HIV) infection iv. congenital heart defects repaired greater than 1 year prior to screening (i.e., atrial septal defects, ventricular septal defects, and patent ductus arteriosus) NB: subjects with portopulmonary hypertension and pulmonary veno-occlusive disease are NOT eligible for the study

• Subject must have a current diagnosis of being in World Health Organisation (WHO) Functional Class II or III.

• Subject must meet all of the following haemodynamic criteria by means of a right heart catheterization prior to screening:

  i. mPAP of ≥25 mmHg ii. PVR ≥ 300 dynes/sec/cm5 iii. PCWP or LVEDP of ≤12 mmHg if PVR ≥300 to <500 dyne/sec/cm5 , or PCWP/LVEDP ≤ 15 mmHg if PVR ≥500 dynes/sec/cm5

• Subject must walk a distance of ≥125m and ≤500m at the screening visit

Exclusion Criteria:

• Subject received previous PAH therapy (phosphodiesterase type 5 inhibitor (PDE5i), endothelin receptor antagonist (ERA), chronic prostanoid*) within 4 weeks prior to the screening visit (*Chronic prostanoid use is considered >7 days of treatment)
• Subject received ERA treatment (e.g., bosentan or sitaxentan) or PDE5i treatment (e.g. Sildenafil) at any time AND discontinued due to tolerance issues other than those associated with liver function abnormalities
• Subjects who have previously discontinued ambrisentan or tadalafil in either another clinical study or commercial product (Volibris/Letairis or Adcirca) for safety or tolerability reasons.

Sex/Gender

• Sexes Eligible for Study: All

• Ages: 18 Years to 75 Years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Contacts: Contact information is only displayed when the study is recruiting subjects
• Listed Location Countries: Australia, Austria, Belgium, Canada, France, Germany, Greece, Italy, Japan, Netherlands, Spain, Sweden, United Kingdom, United States

Administrative Information

• NCT Number: NCT01178073
• Other Study ID Numbers: 112565
• Has Data Monitoring Committee: Yes
• U.S. FDA-regulated Product: Not Provided
• IPD Sharing Statement: Not Provided
• Current Responsible Party: GlaxoSmithKline
• Original Responsible Party: Not Provided
• Current Study Sponsor: GlaxoSmithKline
• Original Study Sponsor: Same as current
• Collaborators: Gilead Sciences

Investigators

• Study Director: GSK Clinical Trials; GlaxoSmithKline

• PRS Account: GlaxoSmithKline
• Verification Date: August 2017