NCT07143448

Brief Summary

Phase 1b/2 Study of HS235 Assessing the Safety, Pharmacokinetics, Pharmacodynamics, and Efficacy of the Activin Signaling Inhibitor HS235 Added to Background Treatment in Adults with Pulmonary Arterial Hypertension (PAH)

Trial Health

80
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
90

participants targeted

Target at P75+ for phase_1

Timeline
25mo left

Started Aug 2026

Typical duration for phase_1

Geographic Reach
3 countries

4 active sites

Status
recruiting

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

Study Progress6%
Aug 2026Nov 2028

First Submitted

Initial submission to the registry

August 20, 2025

Completed
7 days until next milestone

First Posted

Study publicly available on registry

August 27, 2025

Completed
12 months until next milestone

Study Start

First participant enrolled

August 19, 2026

Completed
1.5 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

March 1, 2028

Expected
8 months until next milestone

Study Completion

Last participant's last visit for all outcomes

November 1, 2028

Last Updated

September 11, 2026

Status Verified

September 1, 2026

Enrollment Period

1.5 years

First QC Date

August 20, 2025

Last Update Submit

September 9, 2026

Conditions

Pulmonary Arterial Hypertension

Outcome Measures

Primary Outcomes (1)

  • Incidence and Number of Adverse Events (AEs)

    An AE is any untoward medical occurrence in a participants or clinical trial participants administered a pharmaceutical product and which does not necessarily have a causal relationship with this treatment. The incidence and number of participants who experience an AE will be reported.

    up to 29 weeks

Study Arms (2)

HS235

EXPERIMENTAL

HS235 Subcutaneous Injection

Biological: HS235

Placebo

PLACEBO COMPARATOR

Subcutaneous Injection

Other: Placebo

Interventions

HS235BIOLOGICAL

Subcutaneous Injection

HS235
PlaceboOTHER

Subcutaneous Injection

Placebo

Eligibility Criteria

Age18 Years+
Sexall
Healthy VolunteersNo
Age GroupsAdult (18-64), Older Adult (65+)

You may qualify if:

  • Participants are eligible to be included in the study only if they meet all of the following criteria:
  • Male and female participants, 18 years of age and older.
  • Body Mass Index (BMI) 18.5 and 40 kg/m2 and body weight at or below 120 kg.
  • Baseline RHC performed during the Screening Period documenting:
  • A minimum PVR of ≥ 5 Wood units (WU) or ≥ 400 dyn·sec·cm-5 and,
  • A pulmonary artery wedge pressure (PAWP) of ≤ 15 mm Hg.
  • Diagnosis of WHO pulmonary arterial hypertension (PAH) Group 1.
  • Symptomatic PAH classified as WHO Functional class II to IV.
  • On stable doses of at least 2 approved background PAH therapies and diuretics.
  • Minute Walk Distance (6MWD) ≥ 150 m and ≤ 500 m repeated twice during screening.
  • Ability to adhere to study visit schedule and understand and comply with all protocol requirements.

You may not qualify if:

  • PH WHO Groups 2, 3, 4 or 5.
  • Hospitalization for any worsening medical condition or major surgery within 4 weeks prior to screening.
  • Any symptomatic coronary disease events.
  • History of heart transplant or on heart transplant list.
  • Uncontrolled systemic hypertension.
  • History of restrictive, constrictive or congestive cardiomyopathy.
  • History of significant mitral regurgitation or aortic regurgitation valvular disease.
  • Untreated or poorly controlled moderate or severe obstructive sleep apnea.
  • A diagnosis of worse than moderate COPD or worse than mild ILD.
  • Cerebrovascular event within 90 days prior to screening
  • A pneumonectomy or lobectomy
  • Having received an activin signaling inhibitor such as sotatercept at any time prior to screening
  • A Hgb \> sex-specific ULN
  • Platelets count \< 100,000/mm3
  • Severe (stage ≥4) renal failure with eGFR \< 30 mL/min/m2
  • +1 more criteria

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (4)

Investigational Site-102

Tampa, Florida, 33620, United States

RECRUITING

Investigational Site-104

Providence, Rhode Island, 02903, United States

RECRUITING

Investigational Site-305

Barcelona, 08035, Spain

RECRUITING

Investigational Site-903

London, London, W12 0HS, United Kingdom

RECRUITING

MeSH Terms

Conditions

Pulmonary Arterial Hypertension

Condition Hierarchy (Ancestors)

Hypertension, PulmonaryLung DiseasesRespiratory Tract Diseases

Central Study Contacts

US GSK Clinical Trials Call Center

CONTACT

877-379-3718GSKClinicalSupportHD@gsk.com

EU GSK Clinical Trials Call Center

CONTACT

+44 (0) 20 89904466GSKClinicalSupportHD@gsk.com

Study Design

Study Type
interventional
Phase
phase 1
Allocation
RANDOMIZED
Masking
QUADRUPLE
Who Masked
PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
Purpose
TREATMENT
Intervention Model
SEQUENTIAL
Sponsor Type
INDUSTRY
Responsible Party
SPONSOR

Study Record Dates

First Submitted

August 20, 2025

First Posted

August 27, 2025

Study Start

August 19, 2026

Primary Completion (Estimated)

March 1, 2028

Study Completion (Estimated)

November 1, 2028

Last Updated

September 11, 2026

Record last verified: 2026-09

Locations

GB(1)ES(1)US(2)