AUSTIN, Texas, Sept. 17, 2025 (GLOBE NEWSWIRE) -- Rein Therapeutics ("Rein") (NASDAQ: RNTX), a biopharmaceutical company advancing a novel pipeline of first-in-class medicines to address significant unmet medical needs in orphan pulmonary and fibrosis indications, today announced the publication of novel data on its lead drug candidate, LTI-03, in iScience, a peer-reviewed, open-access journal published by Cell Press.

The paper, titled “LTI-03 peptide demonstrates anti-fibrotic activity in ex vivo lung slices from IPF patients,” reports how LTI-03 was tested directly on lung tissue donated by patients with idiopathic pulmonary fibrosis (IPF) who underwent lung transplant. In this model, LTI-03 showed signs of reducing scarring and protecting lung cells, reinforcing its potential as an important new therapy.

Key Highlights

1. The study used real lung tissue donated by IPF patients. These samples continued to show scarring activity for several days, making them a highly relevant way to test new therapies.
2. LTI-03 reduced multiple scarring pathways (including TGFβ, VEGF, PDGF, and FGF), while also lowering collagen production and inflammatory signals in diseased lung tissue.
3. Unlike nintedanib, the FDA-approved standard-of-care drug, LTI-03 achieved these effects without causing cell damage or death in patient samples, reinforcing the drug’s strong safety profile.
4. The findings add to the growing body of evidence that LTI-03 has the potential to become a meaningful new therapy for IPF.

Brian Windsor, PhD, Chief Executive Officer of Rein Therapeutics, commented, “Using a highly relevant translational model, this peer-reviewed publication provides further validation of LTI-03’s broad anti-fibrotic effects in IPF lung tissue. These data support our ongoing Phase 2 RENEW trial, where we are evaluating LTI-03 in patients living with IPF, a disease with very limited treatment options and high unmet need.”

Urgent Need

IPF is a progressive fibrotic lung disease that affects approximately 100,000 people in the U.S. and more than 70,000 in the U.K. Median survival is just 3–5 years from diagnosis, even with currently approved therapies. The global market for IPF treatments is projected to exceed $11 billion by 2031, underscoring the urgent need for more effective approaches.

Next Steps

Rein recently announced regulatory approval from the U.K.’s MHRA to initiate the Phase 2 RENEW trial of LTI-03. The trial will evaluate safety, tolerability, and changes in lung function in up to 120 patients, with initial data expected in 2026.

The full article can be found here: https://www.cell.com/iscience/fulltext/S2589-0042(25)01698-0

About Rein Therapeutics

Rein Therapeutics is a clinical-stage biopharmaceutical company advancing a novel pipeline of first-in-class therapies to address significant unmet medical needs in orphan pulmonary and fibrosis indications. Rein's lead product candidate, LTI-03, is a novel, synthetic peptide with a dual mechanism targeting alveolar epithelial cell survival as well as inhibition of profibrotic signaling. LTI-03 has received Orphan Drug Designation in the U.S. and is in clinical development. Rein's second product candidate, LTI-01, is a proenzyme that has completed Phase 1b and Phase 2a clinical trials for the treatment of loculated pleural effusions. LTI-01 has received Orphan Drug Designation in the U.S. and E.U. and Fast Track Designation in the U.S.

Forward-Looking Statements

This press release may contain forward-looking statements of Rein Therapeutics, Inc. ("Rein", the "Company", "we", "our" or "us") within the meaning of the Private Securities Litigation Reform Act of 1995, including statements with respect to expectations for the Company’s LTI-03 product candidate. We use words such as "anticipate," "believe," "estimate," "expect," "hope," "intend," "may," "plan," "predict," "project," "target," "potential," "would," "can," "could," "should," "continue," and other words and terms of similar meaning to help identify forward-looking statements, although not all forward-looking statements contain these identifying words. Actual results may differ materially from those indicated by such forward-looking statements as a result of various important factors as well as the risks disclosed in the "Risk Factors" section of the Company's Annual Report on Form 10-K for the year ended December 31, 2024, which is on file with the United States Securities and Exchange Commission (the "SEC") and in subsequent filings that the Company files with the SEC. These forward-looking statements should not be relied upon as representing the Company's view as of any date after the date of this press release, and we expressly disclaim any obligation to update any forward-looking statements, whether as a result of new information, future events or otherwise, except as required by law.

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