United Therapeutics Reports Landmark Phase 3 Results for Ralinepag in Pulmonary Arterial Hypertension

Key Highlights

• Ralinepag Achieves 55% Risk Reduction in Clinical Worsening for PAH Patients: The pivotal Phase 3 ADVANCE OUTCOMES study met its primary endpoint, with ralinepag reducing the risk of clinical worsening events by 55% versus placebo (hazard ratio 0.45, 95% CI [0.33-0.62]; p<0.0001).
• Strong Secondary Endpoints: Statistically significant improvements were observed in secondary measures, including a 47% increased odds of clinical improvement, six-minute walk distance (6MWD), and NT-proBNP reduction at Week 28.
• Robust Efficacy in Challenging Patient Population: 80% of trial participants were on dual background therapy, and 70% were WHO/NYHA Functional Class II, indicating a pre-treated, symptomatic group where treatment advances are highly valuable.
• Favorable Safety Profile: Ralinepag was well-tolerated, with no new safety signals and adverse events consistent with known prostacyclin-related side effects.
• Potential to Redefine PAH Treatment: If approved, ralinepag would become the first and only once-daily oral prostacyclin, offering convenient and potent long-term therapy for patients with pulmonary arterial hypertension.
• Regulatory Plans: United Therapeutics plans to submit a New Drug Application (NDA) to the FDA in the second half of 2026.
• Market Impact: The results solidify United Therapeutics’ leadership in PAH treatment and could significantly increase the addressable patient population if ralinepag is approved.

Details for Investors

United Therapeutics Corporation (Nasdaq: UTHR) has announced positive top-line results from its pivotal Phase 3 ADVANCE OUTCOMES trial evaluating ralinepag, a next-generation oral prostacyclin receptor agonist, in patients with pulmonary arterial hypertension (PAH). The study demonstrated a highly statistically significant 55% reduction in the risk of clinical worsening compared to placebo, a result that is both clinically meaningful and likely to be seen as a major advance by the investment community.

The ADVANCE OUTCOMES trial enrolled 687 PAH patients globally, randomizing them to either ralinepag or placebo on top of standard-of-care background therapy. Notably, 80% of these patients were already on dual background therapy while 70% were classified as WHO/New York Heart Association (NYHA) Functional Class II, reflecting a population with moderate functional limitation but considerable disease burden.

Secondary endpoints provided further evidence of benefit, including a 47% increased odds of clinical improvement by Week 28, as well as statistically significant improvements in six-minute walk distance and NT-proBNP, both important measures of disease severity and progression. These benefits were consistent across all patient subgroups, including time since diagnosis, disease etiology, baseline exercise capacity, and use of other therapies, highlighting ralinepag’s broad therapeutic potential.

From a safety perspective, ralinepag was well-tolerated. Adverse events were consistent with existing knowledge of the prostacyclin class, and no new safety signals emerged during this long-term trial.

Potential Impact for Shareholders

• First and Only Once-Daily Oral Prostacyclin: If approved, ralinepag will be uniquely positioned as the only once-daily oral prostacyclin, offering the convenience and potency that could drive substantial uptake, especially among patients who are not candidates for parenteral or inhaled prostacyclin therapies.
• Expansion of Addressable Market: PAH is a life-threatening disease with an estimated 500,000 cases worldwide and about 50,000 in the U.S. However, diagnosis and treatment rates remain low, suggesting potential for significant market expansion as awareness and accessibility improve.
• Regulatory and Commercial Milestone: United Therapeutics intends to submit its NDA to the FDA in the second half of 2026. Approval would represent a major regulatory and commercial milestone for the company, likely to have a positive impact on share value.
• Competitive Differentiation: Ralinepag’s pharmacological profile includes six-fold higher IP receptor affinity than selexipag’s active metabolite, with sustained receptor occupancy and greater potency in increasing cAMP levels, potentially translating to superior efficacy and disease modification.
• Event-Driven Study Design: The use of time to first adjudicated clinical worsening event as the primary endpoint is considered rigorous and clinically meaningful, reinforcing the strength of the data package for regulatory submission and market positioning.

Company and Strategic Context

United Therapeutics, founded by CEO Martine Rothblatt, has a storied history in PAH innovation, driven by a mission to cure rare diseases and expand access to life-saving therapies. The company’s commitment to prostacyclin-based science is further strengthened by these pivotal results, which may pave the way for a new era in PAH management.

The company also noted its ongoing work in organ manufacturing and other rare disease therapies, emphasizing its focus on sustainable, long-term value creation for investors and society.

United Therapeutics will host a webcast to discuss these results in detail and plans to present full data at an upcoming international conference. A replay of the webcast will be available on the company’s investor relations website.

Forward-Looking Statements

This news release contains forward-looking statements regarding the potential regulatory approval and commercial prospects for ralinepag, as well as the impact of these developments on United Therapeutics’ business and market position. Actual results may differ materially due to risks and uncertainties, including those described in the company’s SEC filings.

Disclaimer: This article is intended for informational purposes only and does not constitute investment advice. Investors should conduct their own due diligence and consult with a professional financial advisor before making investment decisions. The information herein is based on United Therapeutics’ public disclosures as of March 2, 2026, and may be subject to change without notice.

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