FREEDOM-C: Oral Treprostinil in Combination With an Endothelin Receptor Antagonist (ERA) and/or a Phosphodiesterase-5 (PDE-5) Inhibitor for the Treatment of Pulmonary Arterial Hypertension (PAH)

United Therapeutics354 enrolled

Overview

This study was an international, multi-center, randomized, double-blind, placebo-controlled study in subjects with PAH who were currently receiving approved therapy for their PAH (i.e., endothelin receptor antagonist and/or phosphodiesterase-5 inhibitor). Study visits occurred at 4 week intervals for 16 weeks; the key measure of efficacy was the 6-minute walk test. Study procedures included routine blood tests, medical history, physical exams, disease evaluation, and exercise tests. One optional substudy was also a part of FREEDOM-C at select centers - a hemodynamic substudy with a right heart catheterization at Baseline and Week 16. Patients who completed all assessments for 16-weeks were also eligible to enter an open-label, extension phase study (FREEDOM - EXT).

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

QUADRUPLE

Enrollment

354

Conditions

Pulmonary Hypertension

Interventions

Eligibility

Sex: ALLMin age: 12 YearsMax age: 70 Years

Medical Language ↔ Plain English

Inclusion Criteria: * Between 12 and 70 years of age, inclusive. * Body weight at least 45 kg (approximately 100 pounds). * PAH that is either idiopathic/heritable (including PAH associated with appetite suppressant/toxin use); PAH associated with repaired congenital systemic-to-pulmonary shunts (repaired ≥ 5 years); PAH associated with collagen vascular disease; or PAH associated with HIV. * Baseline 6-minute walk distance between 150 and 450 meters, inclusive. * Currently receiving an approved endothelin receptor antagonist and/or an approved phosphodiesterase-5 inhibitor for at least 90 days and on a stable dose for at least the last 30 days. * Previous testing (e.g., right heart catheterization, echocardiography) consistent with the diagnosis of PAH. * Reliable and cooperative with protocol requirements. Exclusion Criteria: * Nursing or pregnant. * Received a prostacyclin within the past 30 days. * PAH due to conditions other than noted in the above inclusion criteria. * History of uncontrolled sleep apnea, renal insufficiency, anemia, left sided heart disease, uncontrolled systemic hypertension, or parenchymal lung disease. * Use of an investigational drug within 30 days of Baseline.

Locations (72)

University of Alabama-Birmingham

Birmingham, Alabama, United States

Arizona Pulmonary Specialist

Phoenix, Arizona, United States

University of Arizona Health Science Center

Tucson, Arizona, United States

West Los Angeles VA Healthcare Center

Los Angeles, California, United States

Stanford University, Pulmonary and Critical Care

Palo Alto, California, United States

Outcomes

Primary Outcomes

Six Minute Walk Distance (6MWD)

Placebo corrected change in six minute walk distance (6MWD) from Baseline to Week 16, correlates with the historical clinical standard for assessing patient functional status in the treatment of PAH and is considered an objective measure of patient functional status by the American Thoracic Society (ATS). The six minute walk test was to be conducted 3 to 6 hours after the previous dose of study drug.

Time frame: Baseline and 16 Weeks

Secondary Outcomes

Borg Dyspnea Score

The Borg dyspnea score is a 10-point scale rating the maximum level of dyspnea experienced during the 6-minute walk test. The Borg dyspnea score was assessed immediately following the 6-minute walk test. Scores ranged from 0 (for no shortness of breath) to 10 (for greatest shortness of breath ever experienced).

Time frame: Baseline and 16 Weeks

Clinical Worsening Assessment

Definition of clinical worsening required one of the following: 1. Death (all causes excluding accident) 2. Transplantation or atrial septostomy 3. Clinical deterioration as defined by: 1. Hospitalization as a result of PAH, or 2. ≥ 20% decrease in 6-minute walk distance from Baseline (or too ill to walk) and a decrease in WHO functional class And 3. Initiation of new PAH specific therapy (i.e., ERA, PDE5I, prostacyclin).

Time frame: Baseline and 16 Weeks

Dyspnea-Fatigue Index

The dyspnea-fatigue index has three components, each rated on a scale of 0 to 4, for the magnitude of the task that evokes dyspnea or fatigue, the magnitude of the pace (or effort) with which the task is performed and the associated functional impairment in general activities. The ratings for each component were added to form an aggregate score, which could range from 0, for the worst condition, to 12, for the best.

Time frame: Baseline and 16 Weeks

World Health Organization Functional Classification for PAH

Class I: Patients with pulmonary hypertension but without resulting limitation of physical activity. Ordinary physical activity does not cause undue dyspnea or fatigue, chest pain, or near syncope. Class II: Patients with pulmonary hypertension resulting in slight limitation of physical activity. These patients are comfortable at rest, but ordinary physical activity causes undue dyspnea or fatigue, chest pain or near syncope. Class III: Patients with pulmonary hypertension resulting in marked limitation of physical activity. They are comfortable at rest. Ordinary activity causes undue dyspnea or fatigue, chest pain, or near syncope. Class IV: Patients with pulmonary hypertension with inability to carry out any physical activity without symptoms. These patients manifest signs of right heart failure. Dyspnea and/or fatigue may be present even at rest. Discomfort is increased by any physical activity.

Time frame: Week 16

Six Minute Walk Distance (6MWD)

Placebo corrected change in six minute walk distance (6MWD) from Baseline to Week 12, correlates with the historical clinical standard for assessing patient functional status in the treatment of PAH and is considered an objective measure of patient functional status by the American Thoracic Society (ATS). The six minute walk test was to be conducted 3 to 6 hours after the previous dose of study drug.

Time frame: Baseline and 12 weeks

Six Minute Walk Distance (6MWD)

Placebo corrected change in six minute walk distance (6MWD) from Baseline to Week 8, correlates with the historical clinical standard for assessing patient functional status in the treatment of PAH and is considered an objective measure of patient functional status by the American Thoracic Society (ATS). The six minute walk test was to be conducted 3 to 6 hours after the previous dose of study drug.

Time frame: Baseline and 8 weeks

Six Minute Walk Distance (6MWD)

Placebo corrected change in six minute walk distance (6MWD) from Baseline to Week 4, correlates with the historical clinical standard for assessing patient functional status in the treatment of PAH and is considered an objective measure of patient functional status by the American Thoracic Society (ATS). The six minute walk test was to be conducted 3 to 6 hours after the previous dose of study drug.

Time frame: Baseline and 4 weeks

Change in Symptoms of PAH From Baseline to Week 16

Defined symptoms of PAH including fatigue, dyspnea, edema, dizziness, syncope, chest pain, and orthopnea were assessed at Baseline prior to starting study drug and during the Treatment Phase at Week 16. Severity grade values (i.e., 0, 1, 2, or 3 in increasing severity) were assigned for each symptom. The outcome data describes the change in severity values from Baseline to Week 16 for each defined symptom of PAH.

Time frame: Baseline and 16 weeks