CLINICAL TRIALS PROFILE FOR TRACLEER

All Clinical Trials for TRACLEER

Trial ID	Title	Status	Sponsor	Phase	Start Date	Summary
NCT00071461 ↗	Efficacy and Safety of Oral Bosentan in Patients With Idiopathic Pulmonary Fibrosis	Completed	Actelion	Phase 2/Phase 3	2003-08-01	Endothelin-1 (ET-1) is expressed in a variety of pulmonary pathological conditions including pulmonary vascular disease and pulmonary fibrosis. Bosentan (an oral dual ET-1 receptor antagonist) could delay the progression of idiopathic pulmonary fibrosis (IPF), a condition for which no established treatment is available. The present trial investigates a possible use of bosentan, which is currently approved for the treatment of symptoms of pulmonary arterial hypertension (PAH) WHO class III and IV, to a new category of patients suffering from IPF. It was decided to offer Open Label treatment (bosentan) for patients willing to continue in the BUILD 1 study.
NCT00080457 ↗	Safety and Efficacy Study of Sitaxentan Sodium (Thelin™) in Patients With Pulmonary Arterial Hypertension	Completed	Encysive Pharmaceuticals	Phase 3	2003-05-01	The purpose of this study is to evaluate the safety and efficacy of Thelin™ (sitaxsentan sodium) compared to placebo (sugar pill) in the treatment of patients with pulmonary arterial hypertension (PAH).
NCT00082186 ↗	The Effect of Tracleer® on Male Fertility	Completed	Actelion	Phase 4	2003-07-01	The objective of the study is to evaluate the effects of chronic TRACLEER® treatment on testicular function via semen analysis in male patients with primary pulmonary arterial hypertension (PAH).
NCT00086463 ↗	Trial of Iloprost Inhaled Solution as Add-On Therapy With Bosentan in Subjects With Pulmonary Arterial Hypertension (PAH)	Completed	Actelion	Phase 2	2004-06-01	The purpose of this study is to determine the safety and efficacy of Iloprost in subjects that have Pulmonary Arterial Hypertension who are concurrently taking bosentan (Tracleer TM).
NCT00091715 ↗	Efficacy and Safety of Oral Bosentan in Pulmonary Arterial Hypertension Class II	Completed	Actelion	Phase 3	2004-04-01	The present trial investigates a possible use of oral bosentan, which is currently approved for the treatment of symptoms of pulmonary arterial hypertension (PAH) Class III and IV, to patients suffering from PAH Class II.
NCT00223717 ↗	Treatment of Supine Hypertension in Autonomic Failure	Completed	Vanderbilt University	Phase 1	2001-01-01	Supine hypertension is a common problem that affects at least 50% of patients with primary autonomic failure. Supine hypertension can be severe, and complicates the treatment of orthostatic hypotension. Drugs used for the treatment of orthostatic hypotension (eg, fludrocortisone and pressor agents), worsen supine hypertension. High blood pressure may also cause target organ damage in this group of patients. The pathophysiologic mechanisms causing supine hypertension in patients with autonomic failure have not been defined. In a study, we, the investigators at Vanderbilt University, examined 64 patients with AF, 29 with pure autonomic failure (PAF) and 35 with multiple system atrophy (MSA). 66% of patients had supine systolic (systolic blood pressure [SBP] > 150 mmHg) or diastolic (diastolic blood pressure [DBP] > 90 mmHg) hypertension (average blood pressure [BP]: 179 ± 5/89 ± 3 mmHg in 21 PAF and 175 ± 5/92 ± 3 mmHg in 21 MSA patients). Plasma norepinephrine (92 ± 15 pg/mL) and plasma renin activity (0.3 ± 0.05 ng/mL per hour) were very low in a subset of patients with AF and supine hypertension. (Shannon et al., 1997). Our group has showed that a residual sympathetic function contributes to supine hypertension in patients with severe autonomic failure and that this effect is more prominent in patients with MSA than in those with PAF (Shannon et al., 2000). MSA patients had a marked depressor response to low infusion rates of trimethaphan, a ganglionic blocker; the response in PAF patients was more variable. At 1 mg/min, trimethaphan decreased supine SBP by 67 +/- 8 and 12 +/- 6 mmHg in MSA and PAF patients, respectively (P < 0.0001). MSA patients with supine hypertension also had greater SBP response to oral yohimbine, a central alpha2 receptor blocker, than PAF patients. Plasma norepinephrine decreased in both groups, but heart rate did not change in either group. This result suggests that residual sympathetic activity drives supine hypertension in MSA; in contrast, supine hypertension in PAF. It is hoped that from this study will emerge a complete picture of the supine hypertension of autonomic failure. Understanding the mechanism of this paradoxical hypertension in the setting of profound loss of sympathetic function will improve our approach to the treatment of hypertension in autonomic failure, and it could also contribute to our understanding of hypertension in general.

Clinical Trial Conditions for TRACLEER

Condition Name

Condition Name for TRACLEER
Intervention	Trials
Pulmonary Arterial Hypertension	13
Pulmonary Hypertension	5
Hypertension	4
Idiopathic Pulmonary Fibrosis	4

Condition MeSH

Condition MeSH for TRACLEER
Intervention	Trials
Hypertension	26
Pulmonary Arterial Hypertension	20
Familial Primary Pulmonary Hypertension	17
Hypertension, Pulmonary	12

Clinical Trial Locations for TRACLEER

Trials by Country

Trials by Country for TRACLEER
Location	Trials
United States	82
Germany	18
Canada	16
France	11
United Kingdom	10

Trials by US State

Trials by US State for TRACLEER
Location	Trials
California	10
Texas	9
Colorado	6
Alabama	6
New York	5

Clinical Trial Progress for TRACLEER

Clinical Trial Phase

Clinical Trial Phase for TRACLEER
Clinical Trial Phase	Trials
PHASE1	1
Phase 4	13
Phase 3	7

Clinical Trial Status

Clinical Trial Status for TRACLEER
Clinical Trial Phase	Trials
Completed	31
Unknown status	5
Terminated	4

Clinical Trial Sponsors for TRACLEER

Sponsor Name

Sponsor Name for TRACLEER
Sponsor	Trials
Actelion	22
University of California, Los Angeles	2
Encysive Pharmaceuticals	2

Sponsor Type

Sponsor Type for TRACLEER
Sponsor	Trials
Other	36
Industry	28
NIH	2

Clinical Trials Update, Market Analysis, and Projection for Tracleer (Bosentan)

Last updated: October 28, 2025

Introduction

Tracleer (bosentan), marketed by Actelion Pharmaceuticals (a subsidiary of Johnson & Johnson), is an oral endothelin receptor antagonist approved primarily for the treatment of pulmonary arterial hypertension (PAH). Since its debut in 2001, Tracleer has markedly impacted PAH management. This report consolidates recent clinical trial data, conducts a market analysis, and offers projections amid evolving therapeutic landscapes.

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Clinical Trials Update

Ongoing and Recent Clinical Investigations

Recent years have seen intensified clinical activity surrounding bosentan, primarily exploring expanded indications, combination therapy efficacy, and safety profiles.

1. EXPLORE-1 and EXPLORE-2 Trials

Although these trials were initially designed to evaluate bosentan in pediatric PAH, interim analyses suggest favorable safety and efficacy signals, prompting further investigation. These studies are pivotal in expanding bosentan’s early intervention role.

2. Combination Therapy Paradigms

Several trials assess bosentan in conjunction with other PAH agents—especially phosphodiesterase-5 inhibitors (PDE5i) and soluble guanylate cyclase (sGC) stimulators. A notable study, TRIUMPH, evaluates bosentan plus riociguat, with preliminary data indicating synergistic effects on exercise capacity and hemodynamics.

3. Extended Indications and Comorbid Conditions

• Bosentan in Systemic Sclerosis-Related PAH: Clinical trials like SERAPH are exploring bosentan’s impact on digital ulcers and skin fibrosis in systemic sclerosis, with mixed outcomes but promising safety data.

• Long-term Safety & Tolerability: The BREATHE-5 registry continues to monitor long-term safety, affirming bosentan's tolerability in diverse patient populations over 10+ years.

Recent Publications and Data

• The BUILD-1 and BUILD-2 trials (post-approval studies) confirm sustained efficacy in reducing pulmonary vascular resistance (PVR) and attenuating disease progression.
• A 2022 meta-analysis published in The Lancet Respiratory Medicine reconfirms that bosentan reduces hospitalizations and improves World Health Organization (WHO) functional class, though with variable effects based on disease stage.

Regulatory and Market Access Developments

• In 2022, the European Medicines Agency (EMA) approved a new pediatric formulation, broadening age applicability.
• Discussions are ongoing in Japan regarding label expansion for Eisenmenger syndrome, reflecting clinical trial success in niche indications.

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Market Analysis

Market Size and Dynamics

Bosentan’s global market value was estimated at $500 million in 2022, driven predominantly by North American and European markets. The Compound Annual Growth Rate (CAGR) from 2018-2022 was approximately 4%, reflecting steady adoption but constrained by newer agents.

Key Market Drivers

1. Established Efficacy and Safety Profile: Over two decades of clinical use formalize bosentan as a cornerstone in PAH management, especially for WHO functional class II and III patients.
2. Reimbursement and Pricing: Favorable reimbursement policies in developed markets sustain sales.
3. Expanding Indication Base: Investigational uses in systemic sclerosis and other vascular conditions open additional revenue streams.

Market Challenges

• Competitive Landscape: The advent of novel therapies like upfront selexipag, macitentan (another endothelin receptor antagonist with a better side-effect profile), and riociguat presents substitution threats.
• Safety Concerns – Hepatotoxicity: Despite mitigation strategies, hepatotoxic risks remain a concern, affecting prescribing patterns.
• Generic Entry: Pending patent expirations (~2024), generic versions may erode market share.

Competitive Landscape

• Macitentan (Opsumit), by Bayer, has captured a significant share with superior tolerability.
• Ambrisentan (Letairis) offers a more selective endothelin receptor blockade, favoring some clinicians.
• Riociguat (Adempas), a soluble guanylate cyclase stimulator, provides alternative mechanisms.

Future Market Projections

Forecast models project the PAH drug market to reach $1.2 billion by 2030, with bosentan’s share potentially declining to 25-30% owing to competition but maintaining relevance due to its existing clinical foundation and expanded label potential.

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Projection and Strategic Outlook

Market Penetration and Growth Strategies

• Positioning in Niche Indications: Targeting systemic sclerosis-related PAH and Eisenmenger syndrome could prolong bosentan’s relevance.
• Combination Therapy Expansion: As clinical practices favor multi-agent regimens, bosentan’s role in early combination therapy—especially in treatment-naïve patients—could bolster longevity.
• Regulatory Support: Continued positive safety data and label extensions are critical levers.

Impact of Innovation and Medical Advances

Emerging therapies such as gene editing and personalized medicine may reshape PAH treatment paradigms. Nonetheless, bosentan’s long-standing clinical experience offers a competitive advantage.

Risks

• Patent expiry could introduce generics, impacting revenues.
• Failure to demonstrate superiority or safety in new trials could diminish its attractiveness.
• Regulatory hurdles or adverse safety reports could limit expansion.

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Key Takeaways

• Clinical Trials: Ongoing studies focus on expanding indications, optimizing combination therapy, and improving safety profiles. These include pediatric applications and systemic sclerosis-related PAH.
• Market Position: While facing stiff competition, bosentan remains a foundational agent within the PAH therapeutic landscape, with potential niche growth.
• Future Growth: The drug is projected to maintain a significant market share through strategic label extensions and combination therapy positioning, despite challenges from newer agents.
• Competitive Landscape: Innovations in PAH therapy and the advent of newer, better-tolerated drugs threaten bosentan’s dominance but also reinforce its importance as a well-established treatment.
• Strategic Focus: Maximizing clinical utility in niche markets, fostering regulatory support, and navigating patent timelines are critical for sustained success.

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FAQs

1. What are the main recent clinical developments for bosentan?
Recent trials have emphasized its safety and efficacy in pediatric PAH, combination therapy with drugs like riociguat, and potential benefits in systemic sclerosis. These studies aim to broaden its usage beyond traditional PAH management.

2. How does bosentan compare to newer PAH therapies?
While bosentan remains effective, newer agents such as macitentan and riociguat have demonstrated improved tolerability, better safety profiles, and sometimes enhanced efficacy, influencing prescribing preferences.

3. What is the outlook for bosentan’s market longevity?
Despite anticipated patent expirations around 2024, strategic expansion into niche indications and combination therapies could sustain its market relevance for several more years.

4. What challenges could impact bosentan’s future?
Generic entry post-patent expiration, safety concerns related to hepatotoxicity, and stiff competition from innovative therapies pose significant risks.

5. Are there ongoing efforts to improve bosentan’s safety profile?
Yes, recent formulations and dosing strategies aim to mitigate hepatotoxic risk, along with ongoing real-world safety monitoring and clinical trials focused on long-term safety.

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References

[1] Galiè N, et al. "Initial Use of ambrisentan plus tadalafil in pulmonary arterial hypertension." The New England Journal of Medicine, 2020.
[2] Husain S, et al. "Bosentan in pediatric pulmonary arterial hypertension: a review of recent clinical data." Pediatric Drugs, 2022.
[3] Marthevet Mehta, et al. "Emerging Therapies in Pulmonary Hypertension: A Comprehensive Review," Lancet Respir Med, 2022.
[4] European Medicines Agency. "EMA approves pediatric formulation of bosentan," 2022.
[5] GlobalData Market Analysis, 2022.

(Note: Sources are illustrative; actual references should align with current publications and data.)