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Phase III Clinical Worsening Study of UT-15C in Subjects With PAH Receiving Background Oral Monotherapy

A Phase III, International, Multi-Center, Randomized, Double-Blind, Placebo-Controlled, Clinical Worsening Study of UT-15C in Subjects With Pulmonary Arterial Hypertension Receiving Background Oral Monotherapy

Status
Completed
Phases
Phase 3
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT01560624
Acronym
FREEDOM-EV
Enrollment
690
Registered
2012-03-22
Start date
2012-06-26
Completion date
2018-06-24
Last updated
2020-02-13

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Pulmonary Arterial Hypertension

Keywords

Pulmonary arterial hypertension (PAH), Pulmonary hypertension (PH), Clinical Worsening, Freedom, Freedom-EV, Treprostinil, UT-15C, 6 Minute walk test

Brief summary

This is an international, multicenter, randomized, double-blind, placebo-controlled, event driven study in subjects with pulmonary arterial hypertension.

Detailed description

Study TDE-PH-310 is an international, multicenter, randomized (1:1 oral treprostinil (UT-15C): placebo), double-blind, placebo-controlled study in subjects with pulmonary arterial hypertension (PAH) who are receiving background oral monotherapy for PAH for at least 30 days at randomization. Subjects are randomly allocated to receive oral treprostinil extended-release tablets or placebo by a stratified randomization by type of background therapy (Strata 1: phosphodiesterase type 5 inhibitor \[PDE5-I\] or soluble guanylate cyclase \[sGC\] stimulator; Strata 2: endothelin receptor antagonist \[ERA\]. Subjects are also stratified by baseline 6-minute walk distance (6MWD) less than or equal to 350 m or greater than 350 m. Subjects receive their first dose of study drug (0.125 mg) or matching placebo on the day of randomization. Oral dosing of study drug is continued at 0.125 mg 3 times daily (TID; every 6 to 8 hours) with food. The dose (or matching placebo) is titrated throughout the study up to a maximum dose of 12 mg TID to reach and maintain a tolerated dosing regimen that provided optimal clinical benefit. Once randomized, subjects return for study visits every 4 weeks for the first 12 weeks, then every 12 weeks for the duration of the study. Subjects continue in the study until experiencing clinical worsening, the number of adjudicated events necessary for study closure occurr, or prematurely discontinue participation in the study for any reason other than protocol-specified clinical worsening. At each scheduled visit, subjects undergo efficacy assessments for clinical worsening, exercise capacity (6MWD and Borg dyspnea score), WHO functional class (FC), and plasma N-Terminal pro-brain natriuretic peptide (NT-proBNP). Subjects could participate in an optional hemodynamic sub-study (assessed by RHC). Safety assessments consist of adverse events (AEs), physical examinations, vital signs, 12-lead electrocardiograms (ECGs), and clinical laboratory parameters. Patients who complete all required assessments are eligible to enter a long-term, open-label, extension study (TDE-PH-311).

Interventions

DRUGPlacebo

Placebo

Sponsors

United Therapeutics
Lead SponsorINDUSTRY

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)

Eligibility

Sex/Gender
ALL
Age
18 Years to 75 Years
Healthy volunteers
No

Inclusion criteria

Subject Inclusion Criteria: 1. Voluntarily gave informed consent to participate in the study. 2. Are 18 to 75 years of age (inclusive) at Screening. 3. Women of childbearing potential must practice abstinence from intercourse when in line with their preferred and usual lifestyle, or use 2 different forms of highly effective contraception for the duration of the study, and for at least 30 days after discontinuing study medication. A negative urine pregnancy test is required at Screening and Baseline prior to initiating study medication. 4. Male subjects must consent to use a condom during intercourse for the duration of the study, and for at least 48 hours after discontinuing study medication. 5. Have a diagnosis of symptomatic idiopathic or heritable PAH, PAH associated with connective tissue disease (CTD), PAH associated with HIV infection, PAH associated with repaired congenital systemic-to-pulmonary shunt, or PAH associated with appetite suppressant or toxin use. 6. If known to be positive for HIV infection, have a CD4 lymphocyte count of at least 200 cells/mm\^3 assessed at Screening and are receiving current standard of care anti retroviral or other effective medication for the treatment of HIV infection. 7. Have a baseline 6MWD greater than or equal to 150 m in the absence of a concurrent injury, illness, or other confounding factor including, but not limited to, use of an aid for ambulation or connection to a nonportable machine, that would have prevented the accurate assessment of the subject's exercise capacity. 8. Are optimally treated with conventional pulmonary hypertension therapy with no additions, discontinuations, or dose changes for a minimum of 10 days prior to randomization. The exceptions are the discontinuation or dose changes of anticoagulants and/or dose change of diuretics. 9. Are receiving a PAH-approved oral monotherapy at a minimum dose that complies with the approved prescribing information for the product for at least 30 days prior to randomization and are receiving a stable dose for at least 10 days prior to randomization. 10. Have had previously undergone a cardiac catheterization within 3 years prior to the start of Screening or during the Screening Period, and the most recent assessment documented a pulmonary artery pressure mean of at least 25 mmHg, a pulmonary capillary wedge pressure (PCWP) (or in the event a PCWP could not be reliably obtained, a left ventricular end diastolic pressure \[LVEDP\]) less than or equal to 15 mmHg, and absence of unrepaired congenital heart disease (other than patent foramen ovale). If a reliable PCWP or LVEDP are unable to be obtained during cardiac catheterization, subjects with clinically normal left heart function and absence of clinically relevant mitral valve disease on echocardiography are eligible for enrollment. 11. Undergo echocardiography with evidence of clinically normal systolic and diastolic left ventricular function and absence of any clinically significant left sided heart disease (eg, mitral valve disease). Subjects with clinically insignificant left ventricular diastolic dysfunction due to the effects of right ventricular overload (ie, right ventricular hypertrophy and/or dilatation) are eligible. 12. Have a previous ventilation perfusion lung scan, high-resolution computerized tomography scan of the chest, and/or pulmonary angiography that are consistent with the diagnosis of PAH. 13. Have pulmonary function tests conducted within 6 months before Screening or during the Screening Period to confirm the following: 1. Total lung capacity is at least 60% 2. Forced expiratory volume at 1 second is at least 50% 14. In the opinion of the Principal Investigator, is able to communicate effectively with study personnel and is considered reliable, willing, and likely to cooperate with protocol requirements, including attending all study visits. Subject

Exclusion criteria

1. Is pregnant or lactating. 2. Have previously received oral treprostinil. 3. Have received a PGI2 (except if used during acute vasoreactivity testing) within 30 days prior to randomization or have previous intolerance or significant lack of efficacy to any PGI2 or PGI2 analogue that resulted in discontinuation or inability to titrate that therapy effectively. 4. Have any background conventional therapies for PAH added, removed, or dose-adjusted within 10 days prior to randomization. The exceptions are removal or dose adjustments of anticoagulants and/or dose adjustments of diuretics. 5. Receive their first dose of a PAH-approved oral monotherapy less than 30 days prior to randomization, or have their PAH-approved oral monotherapy dose changed within 10 days prior to randomization, or the subject discontinues any PAH approved therapy within 30 days prior to Screening, or the subject has previously received 2 PAH approved oral therapies at the same time (specifically, a PDE5-I, an ERA, or a sGC stimulator) concomitantly for more than 90 days cumulatively. 6. Have any disease associated with PAH other than CTD, HIV infection, repaired (for at least 1 year) congenital systemic-to-pulmonary shunt, PAH associated with appetite suppressant/toxin use, or have an atrial septostomy. 7. Have a current diagnosis of uncontrolled sleep apnea as defined by their physician. 8. Have a history of ischemic heart disease, including a previous myocardial infarction or symptomatic coronary artery disease within 6 months prior to Screening or a history of left-sided myocardial disease as evidenced by a mean PCWP (or a LVEDP) greater than 15 mmHg or left ventricular ejection fraction less than 40% as assessed by either multigated angiogram, angiography, or echocardiography. 9. Have uncontrolled systemic hypertension as evidenced by systolic blood pressure (BP) greater than 160 mmHg or diastolic BP greater than 100 mmHg. 10. Have alanine aminotransferase or aspartate aminotransferase levels at least 3 times greater than the upper limit of normal, clinically significant liver disease/dysfunction, or known Child-Pugh Class C hepatic disease at Screening. 11. Have any other disease or condition that would interfere with the interpretation of study assessments. 12. Have a musculoskeletal disorder, is using a device to assist walking, or any disease that is likely to limit ambulation, or is connected to a machine that is nonportable. 13. Have an unstable psychiatric condition or is mentally incapable of understanding the objectives, nature, or consequences of the study, or has any condition which in the Investigator's opinion would constitute an unacceptable risk to the subject's safety. 14. Is receiving an investigational drug, have an investigational device in place, or have participated in an investigational drug or device study within 30 days prior to Screening. 15. Have chronic renal insufficiency as defined by either a Screening creatinine value greater than 2.5 mg/dL or the requirement for dialysis. 16. Does not have 3 or more of the following left ventricular disease/dysfunction risk factors: 1. Body mass index at least 30 kg/m\^2 2. History of essential hypertension 3. Diabetes mellitus (any type) 4. Historical evidence of significant coronary artery disease established by any 1 of the following: history of myocardial infarction, percutaneous coronary intervention, or angiographic evidence of coronary artery disease; positive stress test with imaging; previous coronary artery bypass graft; or stable angina.

Design outcomes

Primary

MeasureTime frameDescription
Time to First Clinical Worsening EventFrom randomization to approximately 4 yearsClinical worsening was assessed continuously from randomization until the subject's last study visit. Clinical worsening events were defined as death (all causes), hospitalizations due to worsening pulmonary arterial hypertension (PAH), initiation of an inhaled or infused prostacyclin (PGI2) for the treatment of worsening PAH, disease progression, or unsatisfactory long-term clinical response. All clinical worsening events reported by the study sites were reviewed by the Sponsor Medical Monitors. Once a clinical worsening event occurred, it was entered in the eCRF and a narrative was submitted for review by the Sponsor's Medical Monitor within 48 hours after the event became known to the Investigator or designee. Subsequently, the narratives for subjects with the reported clinical worsening events were sent to an independent adjudication committee. The independent adjudication committee reviewed and adjudicated all clinical worsening events throughout the study.

Secondary

MeasureTime frameDescription
Change in 6-Minute Walk DistanceFrom Baseline to Week 24The intent of the 6-Minute Walk Test (6MWT) is to evaluate exercise capacity associated with carrying out activities of daily living. A baseline 6MWT was performed prior to initiation of study drug on the day of randomization. 6MWTs were conducted at Weeks 4, 8, 12, 24, and every 12 weeks thereafter. The change between Baseline and Week 24 is reported.
Change in Plasma N-Terminal Pro-brain Natriuretic Peptide (NT-proBNP) From Baseline to Week 24From Baseline to Week 24Plasma NT-proBNP concentration is a useful biomarker for the severity of PAH as it is associated with changes in right heart morphology and function. NT-proBNP sample collection occurred at Baseline (prior to starting study drug), Week 12, Week 24, the first Continued Visit, and every other Continued Visit thereafter (ie, Continued Visits 3, 5, 7, etc). NT-proBNP was also assessed at the Study Drug Termination Visit. The change between Baseline and Week 24 is reported.
Change in World Health Organization Functional Class (WHO FC) From Baseline to Week 48Baseline to Week 48The WHO FC for PAH was assessed at Baseline prior to starting study drug, at all subsequent scheduled study visits, and every time the 6MWT was performed for purposes of assessing clinical worsening status.

Countries

Argentina, Australia, Austria, Brazil, Canada, Chile, China, Denmark, France, Germany, Greece, India, Israel, Italy, Mexico, Netherlands, Poland, Singapore, South Korea, Sweden, Taiwan, United Kingdom, United States

Participant flow

Participants by arm

ArmCount
UT-15C
Treprostinil diolamine extended-release tablets (oral) 0.125 to 12 mg TID Treprostinil Diolamine: Active
346
Placebo
Matching placebo tablets (oral) Placebo: Placebo
344
Total690

Baseline characteristics

CharacteristicTotalUT-15CPlacebo
6MWD at Baseline395.7 meters
STANDARD_DEVIATION 96.3
392.9 meters
STANDARD_DEVIATION 92.5
398.5 meters
STANDARD_DEVIATION 100
Age, Categorical
<=18 years
0 Participants0 Participants0 Participants
Age, Categorical
>=65 years
104 Participants54 Participants50 Participants
Age, Categorical
Between 18 and 65 years
586 Participants292 Participants294 Participants
Age, Continuous45.2 years
STANDARD_DEVIATION 15.5
45.6 years
STANDARD_DEVIATION 15.7
44.8 years
STANDARD_DEVIATION 15.4
Etiology of PAH
Collagen Vascular Disease
178 Participants94 Participants84 Participants
Etiology of PAH
Congenital Heart Defect
47 Participants20 Participants27 Participants
Etiology of PAH
HIV Infection
9 Participants2 Participants7 Participants
Etiology of PAH
Idiopathic or Heritable PAH
435 Participants219 Participants216 Participants
Etiology of PAH
Other
21 Participants11 Participants10 Participants
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants0 Participants0 Participants
Race (NIH/OMB)
Asian
306 Participants150 Participants156 Participants
Race (NIH/OMB)
Black or African American
21 Participants8 Participants13 Participants
Race (NIH/OMB)
More than one race
0 Participants0 Participants0 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants0 Participants0 Participants
Race (NIH/OMB)
Unknown or Not Reported
3 Participants1 Participants2 Participants
Race (NIH/OMB)
White
360 Participants187 Participants173 Participants
Region of Enrollment
Europe
99 Participants55 Participants44 Participants
Region of Enrollment
North America
93 Participants39 Participants54 Participants
Region of Enrollment
South America
176 Participants90 Participants86 Participants
Region of Enrollment
Southeast Asia
322 Participants162 Participants160 Participants
Sex: Female, Male
Female
544 Participants275 Participants269 Participants
Sex: Female, Male
Male
146 Participants71 Participants75 Participants
Time since Diagnosis1.35 years
STANDARD_DEVIATION 2.54
1.34 years
STANDARD_DEVIATION 2.5
1.37 years
STANDARD_DEVIATION 2.58
WHO Functional Class at Baseline
I
22 Participants9 Participants13 Participants
WHO Functional Class at Baseline
II
433 Participants205 Participants228 Participants
WHO Functional Class at Baseline
III
234 Participants131 Participants103 Participants
WHO Functional Class at Baseline
IV
1 Participants1 Participants0 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
deaths
Total, all-cause mortality
17 / 34618 / 344
other
Total, other adverse events
342 / 346328 / 344
serious
Total, serious adverse events
116 / 346110 / 344

Outcome results

Primary

Time to First Clinical Worsening Event

Clinical worsening was assessed continuously from randomization until the subject's last study visit. Clinical worsening events were defined as death (all causes), hospitalizations due to worsening pulmonary arterial hypertension (PAH), initiation of an inhaled or infused prostacyclin (PGI2) for the treatment of worsening PAH, disease progression, or unsatisfactory long-term clinical response. All clinical worsening events reported by the study sites were reviewed by the Sponsor Medical Monitors. Once a clinical worsening event occurred, it was entered in the eCRF and a narrative was submitted for review by the Sponsor's Medical Monitor within 48 hours after the event became known to the Investigator or designee. Subsequently, the narratives for subjects with the reported clinical worsening events were sent to an independent adjudication committee. The independent adjudication committee reviewed and adjudicated all clinical worsening events throughout the study.

Time frame: From randomization to approximately 4 years

ArmMeasureValue (MEAN)Dispersion
UT-15CTime to First Clinical Worsening Event60.58 weeksStandard Deviation 42.93
PlaceboTime to First Clinical Worsening Event49.31 weeksStandard Deviation 46.28
p-value: 0.027595% CI: [0.56, 0.97]Cox proportion-hazard model
p-value: 0.0391Log Rank
Secondary

Change in 6-Minute Walk Distance

The intent of the 6-Minute Walk Test (6MWT) is to evaluate exercise capacity associated with carrying out activities of daily living. A baseline 6MWT was performed prior to initiation of study drug on the day of randomization. 6MWTs were conducted at Weeks 4, 8, 12, 24, and every 12 weeks thereafter. The change between Baseline and Week 24 is reported.

Time frame: From Baseline to Week 24

ArmMeasureGroupValue (MEAN)Dispersion
UT-15CChange in 6-Minute Walk DistanceWeek 24395.4 metersStandard Deviation 120
UT-15CChange in 6-Minute Walk DistanceBaseline392.9 metersStandard Deviation 92.5
PlaceboChange in 6-Minute Walk DistanceWeek 24372.3 metersStandard Deviation 163
PlaceboChange in 6-Minute Walk DistanceBaseline398.5 metersStandard Deviation 100
p-value: 0.091395% CI: [0, 16]ANCOVA
Secondary

Change in Plasma N-Terminal Pro-brain Natriuretic Peptide (NT-proBNP) From Baseline to Week 24

Plasma NT-proBNP concentration is a useful biomarker for the severity of PAH as it is associated with changes in right heart morphology and function. NT-proBNP sample collection occurred at Baseline (prior to starting study drug), Week 12, Week 24, the first Continued Visit, and every other Continued Visit thereafter (ie, Continued Visits 3, 5, 7, etc). NT-proBNP was also assessed at the Study Drug Termination Visit. The change between Baseline and Week 24 is reported.

Time frame: From Baseline to Week 24

Population: Subjects who did not have a valid NT-proBNP measurement at Baseline or Week 24 were excluded from the analysis.

ArmMeasureValue (LEAST_SQUARES_MEAN)Dispersion
UT-15CChange in Plasma N-Terminal Pro-brain Natriuretic Peptide (NT-proBNP) From Baseline to Week 240.7859 Ratio to baselineStandard Error 1.0547
PlaceboChange in Plasma N-Terminal Pro-brain Natriuretic Peptide (NT-proBNP) From Baseline to Week 241.1230 Ratio to baselineStandard Error 1.05439
p-value: <0.0001ANCOVA
Secondary

Change in World Health Organization Functional Class (WHO FC) From Baseline to Week 48

The WHO FC for PAH was assessed at Baseline prior to starting study drug, at all subsequent scheduled study visits, and every time the 6MWT was performed for purposes of assessing clinical worsening status.

Time frame: Baseline to Week 48

ArmMeasureCategoryValue (COUNT_OF_PARTICIPANTS)
UT-15CChange in World Health Organization Functional Class (WHO FC) From Baseline to Week 48Improved46 Participants
UT-15CChange in World Health Organization Functional Class (WHO FC) From Baseline to Week 48No change203 Participants
UT-15CChange in World Health Organization Functional Class (WHO FC) From Baseline to Week 48Deteriorated66 Participants
PlaceboChange in World Health Organization Functional Class (WHO FC) From Baseline to Week 48Improved38 Participants
PlaceboChange in World Health Organization Functional Class (WHO FC) From Baseline to Week 48No change170 Participants
PlaceboChange in World Health Organization Functional Class (WHO FC) From Baseline to Week 48Deteriorated103 Participants
p-value: 0.0028Fisher Exact

Source: ClinicalTrials.gov · Data processed: Feb 21, 2026