A Phase 2 Study of LTI-03 in Patients With Idiopathic Pulmonary Fibrosis

June 3, 2026 updated by: Rein Therapeutics

A Phase 2, Randomized, Double-Blind, Placebo-Controlled Study of the Safety, Tolerability and Efficacy of Caveolin-1-Scaffolding-Protein-Derived Peptide (LTI-03) in Patients With Idiopathic Pulmonary Fibrosis

Rationale: LTI-03 is an experimental medication breathed into the lungs using an inhaler. It is being studied for the treatment of Idiopathic Pulmonary Fibrosis (IPF). IPF is a progressive, fatal lung disease caused by the death of lung cells involved in oxygen uptake and by progressive fibrosis (scarring) of the lungs. As the disease progresses, patients experience loss of lung function and increased breathing problems. LTI-03 is hypothesized to treat IPF by protecting and restoring the function of the oxygen uptake cells and by controlling lung fibrosis which may result in improving lung scarring.

The purpose of this research is to evaluate LTI-03 including: its safety, whether it causes side effects, whether it improves lung scarring, and whether it improves IPF symptoms. LTI-03 will be compared to placebo in patients diagnosed with IPF within the last 5 years. Patients on a stable dose of nintedanib, pirfenidone, or nerandomilast (if available by prescription) may participate.

Trial Design: This is a Phase 2, randomized, double-blind, placebo-controlled, multi-center study that includes a 28-day Screening Period, a 24-week Treatment Period, and 4-week Follow-up Period.

Study Assessments: Up to 9 visits to the study clinic will be required.

Safety and tolerability will be evaluated with the following assessments: physical examination; collection of vital sign data (heart rate, blood pressure, respiratory rate and peripheral oxygen saturation [SpO2] via pulse oximetry); heart data collected by 12-lead electrocardiogram; and collection of blood samples for safety laboratory tests. In addition, participants will be asked about any adverse events (side effects) they have experienced between clinic visits, if they have changed any medications, and if they are able to properly use their study drug inhaler.

Participants will undergo a lung function test (spirometry) at every visit, which will be used to evaluate both safety and efficacy. Another test measuring the diffusion capacity of the lungs for carbon monoxide (DLCO) will be required at Screening only.

Blood samples will also be collected at each visit to measure disease biomarkers. At select visits patients will be asked to complete the Living with Pulmonary Fibrosis questionnaire to evaluate their IPF symptoms. Participants will also undergo a specialized lung scan (HRCT) at Baseline and at the End of Treatment to measure changes in lung fibrosis.

Interventions: LTI-03 and placebo are provided in powder-filled capsules that participants will self- administer using an inhaler. Placebo capsules look like LTI-03 capsules but have no active ingredients. Approximately 120 participants will be randomly assigned in a blinded manner to one of study drug treatment groups.

Study Overview

Status

Recruiting

Conditions

Intervention / Treatment

Study Type

Interventional

Enrollment (Estimated)

120

Phase

  • Phase 2

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 Backup

Study Locations

  • Australia
    • Tasmania
      • Launceston, Tasmania, Australia, 7250
        • Recruiting
        • Launceston Respiratory and Sleep Centre
        • Contact:
        • Principal Investigator:
          • Collin Chia, MD
  • Poland
    • Silesian Voivodeship
      • Sosnowiec, Silesian Voivodeship, Poland, 41-208
        • Recruiting
        • Salus Aegroti Praktyka Lekarska dr n. med. Grzegorz Gąsior
        • Contact:
        • Principal Investigator:
          • Grzegorz Gasior, MD, PhD
  • United Kingdom
    • Cambridge
      • Trumpington, Cambridge, United Kingdom, CB2 0AY
        • Recruiting
        • Royal Papworth Hospital
        • Principal Investigator:
          • Helen Parfrey, MD
        • Contact:
    • Devon
      • Exeter, Devon, United Kingdom, EX2 5DW
        • Recruiting
        • Royal Devon and Exeter Hospital
        • Contact:
        • Principal Investigator:
          • Michael Gibbons, MD
    • Scotland
      • Edinburgh, Scotland, United Kingdom, EH16 4SA
        • Recruiting
        • Royal Infirmary of Edinburgh
        • Contact:
        • Principal Investigator:
          • Manjit Cartlidge, MD
  • United States
    • Alabama
      • Birmingham, Alabama, United States, 35233
        • Recruiting
        • UAB Lung Health Center
        • Principal Investigator:
          • Tejaswini Kulkarni, MD
        • Contact:
    • California
      • San Diego, California, United States, 92108
        • Recruiting
        • Paradigm Clinical Research Centers, LLC
        • Principal Investigator:
          • Daniel Jones, MD
        • Contact:
    • Colorado
      • Denver, Colorado, United States, 80206
        • Recruiting
        • National Jewish Health
        • Contact:
        • Principal Investigator:
          • Evans Fernandez Perez, MD
    • Connecticut
      • New Haven, Connecticut, United States, 06511
        • Recruiting
        • Yale University School of Medicine
        • Principal Investigator:
          • Danielle Antin-Ozerkis, MD
        • Contact:
    • Florida
      • Weston, Florida, United States, 33331
        • Recruiting
        • Cleveland Clinic Florida
        • Contact:
        • Principal Investigator:
          • David Zisman, MD
    • Michigan
      • Detroit, Michigan, United States, 48202
        • Recruiting
        • Henry Ford Health
        • Contact:
        • Principal Investigator:
          • Asif M. Abdul Hameed, MD
    • Missouri
      • Chesterfield, Missouri, United States, 63017
        • Recruiting
        • The Lung Research Center, LLC
        • Principal Investigator:
          • Neil Ettinger, MD
        • Contact:
      • Kansas City, Missouri, United States, 66160
        • Recruiting
        • University of Kansas Medical Center
        • Principal Investigator:
          • Mark Hamblin, MD
        • Contact:
    • North Carolina
      • Chapel Hill, North Carolina, United States, 27514
        • Recruiting
        • University of North Carolina At Chapel Hill
        • Principal Investigator:
          • Jason Lobo, MD
        • Contact:
          • Adam Souter
    • South Carolina
      • Charleston, South Carolina, United States, 29425
        • Recruiting
        • Medical University of South Carolina
        • Principal Investigator:
          • Timothy Whelan, MD
        • Contact:
    • Texas
      • El Paso, Texas, United States, 79902

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

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  1. Male or female age 40 years or older.
  2. Willing and able to provide written informed consent.
  3. Diagnosis of IPF within 5 years of Screening as confirmed by a centrally read HRCT of the chest as defined by the ATS/ERS/JRS/ALAT guideline. HRCT lung fibrosis by central read during screening must involve ≥ 10% of the lung and be greater than emphysema involvement of the lung.
  4. Forced vital capacity (FVC) percent predicted ≥ 45% at Screening.
  5. Diffusion capacity of the lungs for carbon monoxide (DLCO), hemoglobin-corrected percent predicted ≥ 30% within 8 weeks prior to Randomization.
  6. Participants receiving nintedanib, pirfenidone, or nerandomilast (where approved for marketing) for IPF treatment must have been on a stable prescribed dose for at least 12 weeks prior to Randomization.
  7. Participants who previously received nintedanib, pirfenidone, or nerandomilast must have discontinued treatment at least 8 weeks prior to Randomization.
  8. Able to adequately self-administer study drug using the protocol-specified inhaler device.

Exclusion Criteria:

  1. Forced expiratory volume in 1 second (FEV1)/FVC < 0.7 at Screening.
  2. Use of N-acetyl cysteine or other supplements including but not limited to quercetin, omega-3 fatty acids, dehydroepiandrosterone, polyphenols, and phytochemicals within 7 days prior to Randomization and through Week 24.
  3. Use of systemic corticosteroids at doses > 10 mg/day of prednisone or equivalent within 28 days prior to Randomization.
  4. Active smoker.
  5. Pulmonary exacerbation within 3 months prior to Screening.
  6. Febrile pulmonary illness requiring antibiotic treatment within 28 days prior to Randomization.
  7. Participation in a clinical study or treatment with an investigational drug or device within 28 days of the Screening Visit (or 5 half-lives of the investigational agent, whichever is longer).
  8. History or evidence at Screening of significant renal impairment with estimated glomerular filtration rate (eGFR) < 30 mL/min/1.73m2.
  9. History or evidence at Screening of significant hepatic impairment with bilirubin > 3 mg/dL (> 51.3 μmol/L) and albumin < 2.8 g/dL (<28 g/L) and PT prolongation > 6 sec or INR > 2.3 while not on anticoagulant medication.
  10. Active or history of malignancies within 5 years prior to Randomization, with the exception of localized nonmetastatic basal or squamous cell carcinoma of the skin, in situ carcinoma of the cervix, or prostate cancer.

  11. Serious or active medical or psychiatric condition which, in the opinion of the Investigator, may interfere with treatment, assessment, or compliance with the protocol; or an expected survival of less than 24 weeks.

    Contraception and Pregnancy

  12. Positive pregnancy test in female participants of childbearing potential (defined below).
  13. Female participants who are lactating.
  14. Females of childbearing potential (FOCBP) and men with partners of childbearing potential who do not agree to use an acceptable form of contraception for the duration of study treatment and for at least 90 days after the last dose of study drug. Male participants who do not agree to refrain from donating sperm during this same period.

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: Triple

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: (1) 2.5 mg LTI-03 capsule BID
Caveolin-1-Scaffolding-Protein-Derived Peptide
Drug: LTI-03
Caveolin-1-Scaffolding-Protein-Derived Peptide
Device: Dry Powder Inhaler
Plastiape Monodose RS01 Model 7
Experimental: (2) 2.5 mg LTI-03 capsules BID
Caveolin-1-Scaffolding-Protein-Derived Peptide
Drug: LTI-03
Caveolin-1-Scaffolding-Protein-Derived Peptide
Device: Dry Powder Inhaler
Plastiape Monodose RS01 Model 7
Placebo Comparator: (1) Placebo capsule BID
Lactose powder
Drug: Placebo
Lactose powder
Device: Dry Powder Inhaler
Plastiape Monodose RS01 Model 7
Placebo Comparator: (2) Placebo capsules BID
Lactose powder
Drug: Placebo
Lactose powder
Device: Dry Powder Inhaler
Plastiape Monodose RS01 Model 7

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Time Frame
Safety and Tolerability as measured by the incidence of treatment-emergent adverse events (TEAEs)
Time Frame: Day 1 through Week 24
Day 1 through Week 24

Secondary Outcome Measures

Outcome Measure
Time Frame
Change from baseline in forced vital capacity (FVC)
Time Frame: Day 1 through Week 24
Day 1 through Week 24
Change from baseline in percent predicted FVC
Time Frame: Day 1 through Week 24
Day 1 through Week 24
Change from baseline in lung fibrosis measured by high resolution computed tomography (HRCT)
Time Frame: Day 1 through Week 24
Day 1 through Week 24

Collaborators and Investigators

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

Sponsor

Rein 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)

February 2, 2026

Primary Completion (Estimated)

September 30, 2027

Study Completion (Estimated)

December 31, 2027

Study Registration Dates

First Submitted

April 28, 2025

First Submitted That Met QC Criteria

May 5, 2025

First Posted (Actual)

May 13, 2025

Study Record Updates

Last Update Posted (Actual)

June 5, 2026

Last Update Submitted That Met QC Criteria

June 3, 2026

Last Verified

March 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • LTI-03-2001 (RENEW)

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

Yes

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.

Clinical Trials on Idiopathic Pulmonary Fibrosis (IPF)

Clinical Trials on Placebo

Search Similar Trials

Sponsors and Collaborators

Medical Conditions

Drug Interventions

CROs by country

CROs in Bahrain

Conditions

Rare Diseases

Drug Interventions

Dietary Supplements

Sponsor/Collaborators

Locations

Subscribe