An Adaptive Program of IKT-001 in Pulmonary Arterial Hypertension (PAH) (IMPROVE-PAH)

August 31, 2026 updated by: Inhibikase Therapeutics

An Adaptive, 2-Part, Randomized, Double-Blind, Placebo-Controlled Trial to Evaluate the Efficacy and Safety of IKT-001 in Pulmonary Arterial Hypertension (PAH)

This is an adaptive, 2-part, randomized, multicenter, double-blind, placebo-controlled, parallel-group study designed to evaluate the efficacy and safety of IKT-001 in adult participants with WHO Group 1 PAH.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Recruiting

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Estimated)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
486

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Phase 3

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact

The name and contact information for the person who can answer enrollment questions for a clinical study. Each location where the study is being conducted may also have a specific contact, who may be better able to answer those questions.
  • Name: Medical Director, Inhibikase Therapeutics
  • Phone Number: 1-302-295-3800
  • Email: info@inhibikase.com

Study Locations

  • Argentina
    • Buenos Aires
      • Buenos Aires, Buenos Aires, Argentina, 1425
        • Recruiting
        • Sanatorio de la Trinidad Palermo
  • Australia
    • Queensland
      • Auchenflower, Queensland, Australia, 4066
        • Recruiting
        • Pulmonary Hypertension Research Queensland PHRQ
  • Belgium
    • Brussels Capital
      • Anderlecht, Brussels Capital, Belgium, 1070
        • Recruiting
        • Hôpital Universitaire de Bruxelles - Erasme
  • Canada
    • Alberta
      • Edmonton, Alberta, Canada, T6G 2B7
        • Recruiting
        • University of Alberta Hospital
  • France
    • France
      • Le Kremlin-Bicêtre, France, France, 94270
        • Recruiting
        • Hôpital Bicêtre
    • Grand Est
      • Strasbourg, Grand Est, France, 67091
        • Recruiting
        • CHRU Strasbourg
  • Germany
    • Lower Saxony
      • Hanover, Lower Saxony, Germany, 30625
        • Recruiting
        • Medizinische Hochschule Hannover, Abteilung Pneumologie und Infektiologie
  • Italy
    • Monza and Brianza
      • Monza, Monza and Brianza, Italy, 20900
        • Recruiting
        • Fondazione IRCCS San Gerardo dei Tintori
  • Netherlands
    • North Holland
      • Amsterdam, North Holland, Netherlands, 1081 BT
        • Recruiting
        • Amsterdam UMC site VUMC
  • New Zealand
    • Auckland
      • Auckland, Auckland, New Zealand, 1051
        • Recruiting
        • Auckland City Hospital
    • Canterbury
      • Christchurch, Canterbury, New Zealand, 8011
        • Recruiting
        • University of Otago Christchurch
    • Waikato Region
      • Hamilton, Waikato Region, New Zealand, 3204
        • Recruiting
        • Te Whato Ora, Health New Zealand, Waikato Hospital
  • Portugal
    • Porto District
      • Porto, Porto District, Portugal, 4099-001
        • Recruiting
        • Unidade Local de Saúde de Santo António - Hospital de Santo António
  • South Korea
      • Gwangju, South Korea, 61469
        • Recruiting
        • Chonnam National University Hospital
      • Seoul, South Korea, 06351
        • Recruiting
        • Samsung Medical Center
  • Spain
    • Andalusia
      • Málaga, Andalusia, Spain, 29010
        • Recruiting
        • Hospital Universitario Virgen de La Victoria
    • Barcelona
      • Barcelona, Barcelona, Spain, 08036
        • Recruiting
        • Hospital Clínic de Barcelona
    • Cantabria
      • Santander, Cantabria, Spain, 39008
        • Recruiting
        • Hospital Universitario Marques de Valdecilla
    • Catalonia
      • Barcelona, Catalonia, Spain, 08035
        • Recruiting
        • Hospital Universitari Vall d'Hebron
    • Madrid
      • Madrid, Madrid, Spain, 28046
        • Recruiting
        • Hospital Universitario La Paz
      • Madrid, Madrid, Spain, 28041
        • Recruiting
        • Hospital Universitario Doce de Octubre
    • Malaga
      • Marbella, Malaga, Spain, 29603
        • Recruiting
        • Hospital Costa del Sol
    • Sevilla
      • Seville, Sevilla, Spain, 41009
        • Recruiting
        • Hospital Universitario Virgen Macarena
    • Toledo
      • Toledo, Toledo, Spain, 45007
        • Recruiting
        • Hospital General Universitario de Toledo
    • Valencia
      • Valencia, Valencia, Spain, 46026
        • Recruiting
        • Hospital Universitari i Politecnic La Fe de Valencia
  • United Kingdom
      • London, United Kingdom, W12 0HS
        • Recruiting
        • Imperial College Healthcare NHS Trust
    • Cambridgeshire
      • Cambridge, Cambridgeshire, United Kingdom, CB2 0AY
        • Recruiting
        • Royal Papworth Hospital
    • West Dunbartonshire
      • Glasgow, West Dunbartonshire, United Kingdom, G81 4DY
        • Recruiting
        • Golden Jubilee National Hospital
  • United States
    • Arizona
      • Scottsdale, Arizona, United States, 85258
        • Recruiting
        • Arizona Pulmonary Specialists, LTD
    • California
      • Beverly Hills, California, United States, 90211
        • Recruiting
        • Cedars Sinai
      • Santa Barbara, California, United States, 93105
        • Recruiting
        • Jeffrey S. Sager, MD Medical Corporation
      • Torrance, California, United States, 90502
        • Recruiting
        • Lundquist at Harbor UCLA
    • Colorado
      • Aurora, Colorado, United States, 80045
        • Recruiting
        • University of Colorado Anschutz Medical Campus
    • Kansas
      • Kansas City, Kansas, United States, 66103
        • Recruiting
        • University of Kansas Medical Center
    • Kentucky
      • Louisville, Kentucky, United States, 40202
        • Recruiting
        • Norton Healthcare
    • Massachusetts
      • Boston, Massachusetts, United States, 02111
        • Recruiting
        • Tufts Medical Center
    • Missouri
      • St Louis, Missouri, United States, 63110
        • Recruiting
        • Washington University School of Medicine
    • New York
      • New York, New York, United States, 10016
        • Recruiting
        • NYU Langone Health
      • Valhalla, New York, United States, 10595
        • Recruiting
        • Westchester Medical Center
    • North Carolina
      • Durham, North Carolina, United States, 27710
        • Recruiting
        • Duke University
    • Ohio
      • Cincinnati, Ohio, United States, 45267
        • Recruiting
        • University of Cincinnati
    • Tennessee
      • Nashville, Tennessee, United States, 37232-7610
        • Recruiting
        • Vanderbilt University Medical Center
    • Texas
      • Dallas, Texas, United States, 75390
        • Recruiting
        • UT Southwestern Medical Center

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Documented diagnosis of WHO PAH Group 1 in any of the following subtypes:

    • Idiopathic PAH
    • Heritable PAH
    • Drug/toxin-induced PAH
    • PAH associated with connective tissue disease (CTD)
    • PAH associated with simple, congenital systemic-to-pulmonary shunts at least 1 year following repair
  • Men and women 18 and 75 years of age (inclusive)
  • Must have a body mass index (BMI) of ≥18.5 kg/m^2 and ≤35.0 kg/m^2 at screening.
  • Baseline RHC performed during the Screening Period documenting a PVR of ≥ 400 dyn/sec/cm^5 ; pulmonary capillary wedge pressure (PCWP) ≤15 mmHg and mean pulmonary artery pressure (mPAP) >20 mmHg. PVR enrichment criteria to ensure population baseline PVR >700 dynes/sec/cm^5
  • On stable doses of background PAH therapy including endothelin receptor antagonists, phosphodiesterase-5 inhibitors, prostacyclins, and soluble guanylate cyclase stimulators for ≥90 days prior to screening. Current use of sotatercept is not permitted.
  • 6MWD ≥ 100 and ≤ 475 m

Exclusion Criteria:

  • Diagnosis of PAH WHO Groups 2, 3, 4, or 5.
  • Diagnosis of the following PAH Group 1 subtypes: human immunodeficiency virus (HIV)-associated PAH, PAH associated with portal hypertension, schistosomiasis-associated PAH, and pulmonary veno-occlusive disease.
  • Any of the following blood pressure-related values or abnormalities: Uncontrolled systemic hypertension as evidenced by sitting systolic BP >160 mmHg or sitting diastolic BP >100 mmHg at screening, Baseline systolic BP <90 mmHg at screening, Syncope within 3 months prior to screening
  • History of restrictive, constrictive, or congestive cardiomyopathy.
  • ECG with Fridericia's corrected QT interval (QTcF) ≥ 450 msec in males or ≥ 470 msec in females at screening or ≥500 msec in the presence of a right bundle branch block.
  • Personal or family history of long QT syndrome or sudden cardiac death.
  • Presence of a CardioMEMS device or any other implanted hemodynamic monitoring device.
  • Forced vital capacity (FVC) <70 percent on pulmonary function test (PFT) performed no more than 6 months prior to screening; or if FVC is 60 percent to 69 percent, must have a chest computed tomography scan within 12 months with no more than mild interstitial lung disease.
  • History of atrial fibrillation or atrial flutter.
  • History of cerebrovascular accident, intracranial hemorrhage, or subdural hematoma at anytime, or a fall associated with head trauma within 3 months of screening.
  • Acutely decompensated right heart failure within 30 days prior to screening, as per investigator assessment.
  • Clinically significant ischemic, valvular, constrictive heart disease, or heart failure with preserved ejection fraction in the opinion of the investigator.
  • History of pneumonectomy.
  • Untreated or inadequately treated (in the opinion of the investigator) obstructive sleep apnea.

  • Acute or chronic hepatitis B or C infection, defined as:

    • Hepatitis B virus: a positive hepatitis B surface antigen test or a positive hepatitis B core antibody test with detectable DNA
    • Hepatitis C virus (HCV): a positive hepatitis C antibody test with detectable HCV ribonucleic acid (RNA).Participants with a positive hepatitis C antibody test, but no detectable HCV RNA who completed treatment with direct-acting antivirals may be considered after discussion with the medical monitor.
  • History of or currently diagnosed with a bleeding disorder, including but not limited to hemophilia, von Willebrand disease, thrombocytopenia, or significant bleeding history defined as any bleeding event requiring medical intervention.

  • Received treatment with any of the following excluded medications:

    • Currently receiving strong cytochrome P450 (CYP) 3A inducers or CYP3A inhibitors (except for topical administration)
    • Currently receiving or anticipated need to receive any anticoagulant (e.g., heparins, vitamin K antagonists, direct oral anticoagulants, or direct thrombin inhibitors).
    • Current use of sotatercept. Note: participants who previously received sotatercept may be considered if the last dose administered was >6 months prior to screening, participant had no significant bleeding events while on sotatercept.
  • Initiation of an exercise program for cardiopulmonary rehabilitation within 90 days prior to screening or planned initiation during the study (participants who are stable in the maintenance phase of a program and who will continue for the duration of the study are eligible).
  • History of atrial septostomy within 180 days prior to screening.
  • Current participation in another investigational clinical trial and/or receipt of any investigational medication within 90 days prior to screening.
  • Previous randomization into this or another IKT-001 study.
  • Any social, behavioral, or medical reason that would preclude completion of the study, in the judgement of the investigator.
  • Currently lactating, pregnant or planning on becoming pregnant during the study.
  • Prior receipt of a solid organ transplant or stem cell transplant.
  • Planned surgery that would require any study drug interruption or interfere with study assessments during the study (minor procedures may be allowed in consultation with the medical monitor).
  • Malignancy within the last 5 years prior to consent except completely treated non-metastatic-basal cell, squamous cell, in situ cervical cancer, and clinically localized National Comprehensive Cancer Network very low to low risk prostate cancer under active surveillance.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Quadruple

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Experimental: IKT-001
IKT-001 tablets for PO administration
Drug: IKT-001
IKT-001 tablets for PO administration
Placebo Comparator: Placebo
Matching placebo to IKT-001 tablets for PO administration
Drug: Placebo
Placebo to IKT-001 tablets for PO administration

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
[Part B] To characterize the effects of IKT-001 on symptoms and characteristics of Pulmonary Arterial Hypertension compared to placebo
Time Frame: Baseline to Week 24
Change in 6-minute walk distance (6MWD)
Baseline to Week 24
[Part A] To evaluate the effect on Pulmonary Vascular Resistance (PVR) in participants with WHO Group 1 PAH treated with IKT-001 compared to placebo
Time Frame: Baseline to Week 24
Change in Pulmonary Vascular Resistance (PVR)
Baseline to Week 24

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
To characterize the effects of IKT-001 on WHO Functional Class
Time Frame: Baseline up to Week 48
Change in WHO Functional Class
Baseline up to Week 48
To characterize the effects of IKT-001 on time to clinical worsening
Time Frame: Baseline up to Week 48
Time to clinical worsening
Baseline up to Week 48

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
Inhibikase Therapeutics

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
April 23, 2026

Primary Completion (Estimated)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
June 1, 2029

Study Completion (Estimated)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
December 1, 2029

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
January 22, 2026

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
January 22, 2026

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
January 26, 2026

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
September 2, 2026

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
August 31, 2026

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
May 1, 2026

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • IKT-001-201

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

Yes

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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