Sotatercept for Pulmonary Arterial Hypertension

(LIGHTRAY EXT Trial)

Recruiting at 76 trial locations

Overseen By Toll Free Number

Age: 18+

Sex: Any

Trial Phase: Phase 2

Sponsor: Merck Sharp & Dohme LLC

Must not be taking: Activin inhibitors

Disqualifiers: Not in MK-7962-024, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Prior Safety Data This treatment has passed at least one previous human trial

Compensation: Varies

Number of Visits: Unknown

Duration: 24 months

130 Participants Needed

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial tests a treatment called sotatercept for pulmonary arterial hypertension (PAH), which is high blood pressure in the lungs. Researchers aim to determine if weight-banded dosing (based on weight ranges) of sotatercept is safe and well-tolerated over an extended period. Participants who completed an earlier sotatercept study may join this trial, provided they have not started any other sotatercept treatment. As a Phase 2 trial, the research focuses on assessing the treatment's effectiveness in an initial, smaller group of people.

Will I have to stop taking my current medications?

The trial information does not specify if you need to stop taking your current medications. However, you cannot start treatment with commercially available sotatercept or any activin signaling inhibitor other than sotatercept.

Is there any evidence suggesting that sotatercept is likely to be safe for humans?

Research has shown that sotatercept has been tested in people with pulmonary arterial hypertension (PAH) and has raised some safety concerns. In previous studies, more participants taking sotatercept experienced nosebleeds, dizziness, and small red spots on the skin compared to those taking a placebo. Some patients also had higher hemoglobin levels and fewer platelets.

However, sotatercept was associated with a lower risk of death and hospitalization for PAH patients, significantly improving survival rates. While some side effects exist, many patients have tolerated the treatment well. This suggests that sotatercept has a unique safety profile, and ongoing studies continue to assess its long-term safety and effectiveness. ^{1 2 3 4 5}

Why are researchers excited about this trial's treatment for pulmonary arterial hypertension?

Sotatercept is unique because it targets the underlying processes of pulmonary arterial hypertension (PAH) differently than current treatments. Most PAH therapies focus on dilating blood vessels, but sotatercept acts on the transforming growth factor-beta (TGF-β) superfamily, which is involved in cell growth and repair, potentially addressing the root cause of the disease. Additionally, sotatercept is administered via a convenient subcutaneous injection every three weeks, which could improve patient compliance compared to more frequent dosing schedules required by some existing therapies. Researchers are excited about sotatercept because it may offer a new way to manage PAH more effectively and with fewer side effects.

What evidence suggests that sotatercept might be an effective treatment for pulmonary arterial hypertension?

Research shows that sotatercept, which participants in this trial will receive, can help treat pulmonary arterial hypertension (PAH). Studies have found that sotatercept improves exercise capacity and reduces the risk of the condition worsening by 84%. It also lowers the chances of death, the need for a lung transplant, and long hospital stays compared to a placebo. Early results suggest that patients experience better heart function and few side effects, although hemoglobin levels may increase. These findings make sotatercept a promising treatment for PAH. ^{5 6 7 8 9}

Who Is on the Research Team?

Medical Director

Principal Investigator

Merck Sharp & Dohme LLC

Are You a Good Fit for This Trial?

This trial is for people who have Pulmonary Arterial Hypertension (PAH) and participated in a previous study, MK-7962-024 (LIGHTRAY), without discontinuing the intervention. They must not have started treatment with commercially available sotatercept to be eligible.

Inclusion Criteria

I finished the LIGHTRAY study without stopping the treatment and can safely join the LIGHTRAY EXTENSION study.

I have not started treatment with sotatercept.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants receive weight-banded doses of sotatercept via subcutaneous injection every 3 weeks, continuing their background PAH therapy

24 months

Follow-up

Participants are monitored for safety and effectiveness after treatment

4 months

Open-label extension

Participants continue to receive weight-banded doses of sotatercept to evaluate long-term safety and tolerability

Long-term

What Are the Treatments Tested in This Trial?

Interventions

• Sotatercept

Trial Overview The trial is testing Sotatercept given in weight-banded doses as an extension of a prior study. It aims to evaluate the long-term safety and tolerability of this medication when used alongside standard PAH therapies.

How Is the Trial Designed?

Group I: Weight-banded sotatercept dosing Experimental Treatment 2 Interventions

Participants will receive sotatercept via subcutaneous (SC) injection every 3 weeks at an initial dose of up to 45 mg and then at a maintenance dose of up to 90 mg using a weight-banded method and will continue treatment for up to 24 months. All eligible participants will receive weight-banded dosing at the dosing level (initial or maintenance) at which they finished MK-7962-024 (LIGHTRAY). Participants will continue to take their background PAH therapy during the study.

Who Is Running the Clinical Trial?

Merck Sharp & Dohme LLC

Lead Sponsor

Trials

4,096

Recruited

5,232,000+

Chirfi Guindo

Merck Sharp & Dohme LLC

Chief Marketing Officer since 2022

Degree in Engineering from Ecole Centrale de Paris, MBA from New York University Stern School of Business

Robert M. Davis

Merck Sharp & Dohme LLC

Chief Executive Officer since 2021

JD from Northwestern University Pritzker School of Law, MBA from Northwestern University Kellogg Graduate School of Management, Bachelor's in Finance from Miami University

Citations

1. pubmed.ncbi.nlm.nih.gov pubmed.ncbi.nlm.nih.gov/40167274/

Sotatercept in Patients with Pulmonary Arterial ... Background: Sotatercept improves exercise capacity and delays the time to clinical worsening in patients with World Health Organization (WHO) ...

2. jwatch.org jwatch.org/na59304/2025/10/09/sotatercept-beneficial-recent-onset-pulmonary-arterial

Sotatercept Beneficial in Recent-Onset Pulmonary Arterial ... The activin-signaling inhibitor improved clinical outcomes in patients when given within 1 year of PAH diagnosis. ... PAH based on trials in those ...

3. atsjournals.org atsjournals.org/doi/abs/10.1164/ajrccm.2025.211.Abstracts.A7602

Early Outcomes of Sotatercept in Pulmonary Arterial ... Mean RVFWS improved to -19% [-21% to -14.6%] (p = 0.032). Side effects were infrequent, except for an increment in Hb levels by a mean 1.92±1.4 g/dL (p<0.0001).

4. acc.org acc.org/Latest-in-Cardiology/Clinical-Trials/2025/03/28/02/58/zenith

Sotatercept In High-Risk Patients With Pulmonary Arterial ... Treatment with sotatercept resulted in a lower risk of all-cause death, lung transplantation, and hospitalization (≥24 hours) for worsening PAH than placebo.

5. jmcp.org jmcp.org/doi/10.18553/jmcp.2024.30.5.491

The effectiveness and value of sotatercept for pulmonary ... There was an 84% reduction in the risk of clinical worsening with sotatercept as assessed by a composite endpoint of time to first clinical ...

6. nejm.org nejm.org/doi/full/10.1056/NEJMoa2213558

Phase 3 Trial of Sotatercept for Treatment of Pulmonary ... Adverse events that occurred more frequently with sotatercept than with placebo included epistaxis, dizziness, telangiectasia, increased hemoglobin levels, ...

7. pubmed.ncbi.nlm.nih.gov pubmed.ncbi.nlm.nih.gov/40876858/

A New Frontier in Pulmonary Arterial Hypertension Treatment Study selection and data extraction: Phase II and III trials assessing sotatercept's safety and efficacy were included. Initially, 796 trials ...

8. ajmc.com ajmc.com/view/sotatercept-for-pah-maintains-safety-reduced-mortality-in-long-term-follow-up

Sotatercept for PAH Maintains Safety, Reduced Mortality in ... Sotatercept significantly reduced mortality risk by 85% in patients with PAH compared with placebo. · The safety profile of sotatercept remained ...

9. publications.ersnet.org publications.ersnet.org/content/erj/66/4/2501633

Sotatercept in pulmonary arterial hypertension Sotatercept's safety profile is distinct. The main safety signals observed in clinical trials are increased haemoglobin, decreased platelet counts, ...