GRI Bio Presents Positive Pre-Clinical Data Demonstrating GRI-0621 Resolves Inflammation and Fibrosis in Bleomycin-Induced Fibrosis and Reiterates Promising Preliminary Phase 2a Clinical Results

Data presented at the 2025 American Thoracic Society (ATS) International Conference

Pre-clinical and interim clinical results underscore GRI-0621’s potential to have both anti-inflammatory and anti-fibrotic effects in pulmonary fibrosis

Results from 6-week interim analysis (n=24) in ongoing Phase 2a study of GRI-0621 for the treatment of Idiopathic Pulmonary Fibrosis (IPF) anticipated in Q2 2025

/EIN News/ -- LA JOLLA, CA, May 22, 2025 (GLOBE NEWSWIRE) -- GRI Bio, Inc. (NASDAQ: GRI) (“GRI Bio” or the “Company”), a biotechnology company advancing an innovative pipeline of Natural Killer T (“NKT”) cell modulators for the treatment of inflammatory, fibrotic and autoimmune diseases, today announced the presentation of positive preclinical data demonstrating its lead program GRI-0621 has anti-inflammatory and anti-fibrotic effects in pulmonary fibrosis.

The data was presented by Marc Hertz, PhD, Chief Executive Officer of GRI Bio in the poster titled, “Inactivation of iNKT Cells After the Inflammatory Phase Leads to Significant Inhibition of Fibroblast Activation and Fibrosis in a Model of Pulmonary Fibrosis,” as part of the D21 - IMMUNOLOGICAL INSIGHTS IN LUNG INFLAMMATION AND REPAIR session at the 2025 ATS International Conference held on Wednesday, May 21, 2025.

“We continue believe GRI-0621 is a promising potential treatment option for IPF, an indication where there remains significant unmet need. Our growing body of pre-clinical results continue to bolster our understanding of the role of iNKT cell activity in driving pulmonary fibrosis and further support our ongoing Phase 2a study examining the safety and tolerability of GRI-0621 and its effect on various biomarkers in IPF patients. We remain encouraged by the progress made in our Phase 2a biomarker study and look forward to reporting additional data this year,” commented Marc Hertz, PhD, Chief Executive Officer of GRI Bio.

The presented data highlights results from biochemical, qPCR and immunohistochemistry analyses, used to investigate whether iNKT cell inactivation during the fibrotic phase resolves lung injury, fibroblast activation, and fibrosis in the murine bleomycin model of pulmonary fibrosis.

Key Highlights

• In a therapeutic regimen of the bleomycin-induced fibrosis model, orally administered GRI-0621 after completion of the inflammatory phase (Day 7), significantly inhibits lung injury and several important fibrotic cellular and molecular drivers of lung disease, including fibroblast activation and fibrosis.
• GRI-0621 demonstrated to impact key innate and adaptive cell activity, cytokine production, myofibroblast activation, and ECM deposition and fibrosis.
• GRI-0621 inhibition of iNKT cell activity is therapeutic in treatment models of pulmonary fibrosis and performs as well or better than the approved drug nintedanib.
  

GRI Bio’s lead program, GRI-0621, is a small molecule RAR-βɣ dual agonist that inhibits the activity of human iNKT cells. GRI-0621 is currently being assessed in a 12-week, double-blind, randomized, placebo-controlled study in patients with IPF to assess the safety and tolerability of GRI-0621. In addition, the effect of GRI-0621 on a number of biomarkers both from the blood and bronchoalveolar lavage (BAL) will be evaluated. These include several biomarkers associated with disease progression, NKT cell and other immune cell numbers and activity, differential gene expression, as well as pulmonary function tests.

As previously announced, the pre-planned interim analysis for 2-week safety results from the ongoing Phase 2a biomarker study demonstrated GRI-0621 (4.5mg orally once daily) to be safe and well-tolerated in the first 12 patients evaluated per protocol. Hyperlipidemia, as assessed by LDL, HDL and triglyceride (TG) levels, was not seen in the 12 patients assessed at the 2-week visit. There were no meaningful changes in HDL, LDL or TG levels in patients receiving GRI-0621. The interim analysis committee recommended the study should continue as planned. The interim results show that GRI-0621’s receptor selectivity is consistent with the toxicity profile observed in earlier studies evaluating oral tazarotene in over 1,700 patients treated for up to 52 weeks.

Additionally, interim biomarker results from the first 12 subjects at 2 weeks were reviewed by the IDMC and determined that the change from baseline in PRO-C3 of GRI-0621-treated patients compared to placebo patients is suggestive of anti-fibrotic effect. Based on the available interim data reviewed, the IDMC has recommended the Phase 2a study evaluating GRI-0621 to continue as planned as there are no safety concerns seen to date.

Topline results from the Phase 2a biomarker study are expected in the third quarter of 2025.

For more information about the Phase 2a study, please visit clinicaltrials.gov and reference identifier NCT06331624.

About GRI Bio, Inc.

GRI Bio is a clinical-stage biopharmaceutical company focused on fundamentally changing the way inflammatory, fibrotic and autoimmune diseases are treated. GRI Bio’s therapies are designed to target the activity of Natural Killer T (“NKT”) cells, which are key regulators earlier in the inflammatory cascade, to interrupt disease progression and restore the immune system to homeostasis. NKT cells are innate-like T cells that share properties of both NK and T cells and are a functional link between the innate and adaptive immune responses. Type I invariant NKT (“iNKT”) cells play a critical role in propagating the injury, inflammatory response, and fibrosis observed in inflammatory and fibrotic indications. GRI Bio’s lead program, GRI-0621, is an inhibitor of iNKT cell activity and is being developed as a novel oral therapeutic for the treatment of idiopathic pulmonary fibrosis, a serious disease with significant unmet need. The Company is also developing a pipeline of novel type 2 diverse NKT (“dNKT”) agonists for the treatment of systemic lupus erythematosus. Additionally, with a library of over 500 proprietary compounds, GRI Bio has the ability to fuel a growing pipeline.

Forward-Looking Statements

This press release contains “forward-looking statements” within the meaning of the “safe harbor” provisions of the Private Securities Litigation Reform Act of 1995. Forward-looking statements may be identified by the use of words such as “anticipate,” “believe,” “contemplate,” “could,” “estimate,” “expect,” “intend,” “seek,” “may,” “might,” “plan,” “potential,” “predict,” “project,” “target,” “aim,” “should,” “will,” “would,” or the negative of these words or other similar expressions. These forward-looking statements are based on the Company’s current beliefs and expectations. Forward-looking statements include, but are not limited to, statements regarding: the Company’s expectations with respect to development and commercialization of the Company’s product candidates, the timing of initiation or completion of clinical trials and availability of resulting data, the potential benefits and impact of the Company’s clinical trials and product candidates and any implication that the data or results observed in preclinical trials or earlier studies or trials will be indicative of results of later studies or clinical trials, the Company’s beliefs and expectations regarding potential shareholder value and future financial performance, the Company’s beliefs and estimates about its cash and available resources and its ability to fund its planned operations through any particular date, the Company’s beliefs about the timing and outcome of regulatory approvals and potential regulatory approval pathways, the Company’s expected milestones in 2025, and the Company’s beliefs and expectations regarding the sufficiency of its existing cash and cash equivalents to fund its planned operations, its ability to raise additional funds, which may not be available to the Company on acceptable terms, or at all, and capital expenditure requirements. Actual results may differ from the forward-looking statements expressed by the Company in this press release and consequently, you should not rely on these forward-looking statements as predictions of future events. These forward-looking statements are subject to inherent uncertainties, risks and assumptions that are difficult to predict, including, without limitation: (1) the inability to maintain the listing of the Company’s common stock on The Nasdaq Capital Market and to comply with applicable listing requirements; (2) changes in applicable laws or regulations; (3) the inability of the Company to raise financing in the future; (4) the success, cost and timing of the Company’s product development activities; (5) the inability of the Company to obtain and maintain regulatory clearance or approval for its respective products, and any related restrictions and limitations of any cleared or approved product; (6) the inability of the Company to identify, in-license or acquire additional technology; (7) the inability of the Company to compete with other companies currently marketing or engaged in the development of products and services that the Company is currently developing; (8) the size and growth potential of the markets for the Company’s products and services, and their respective ability to serve those markets, either alone or in partnership with others; (9) the failure to achieve any milestones or receive any milestone payments under any agreements; (10) inaccuracy in the Company’s estimates regarding expenses, future revenue, capital requirements and needs for and the ability to obtain additional financing; (11) the Company’s ability to protect and enforce its intellectual property portfolio, including any newly issued patents; and (12) other risks and uncertainties indicated from time to time in the Company’s filings with the U.S. Securities and Exchange Commission (the “SEC”), including the risks and uncertainties described in the “Risk Factors” section of the Company’s most recent Annual Report on Form 10-K filed with the SEC on March 14, 2025 and subsequently filed reports. In particular, the data discussed in this release is interim data and additional study and additional favorable results will be needed for development of GRI-0621 to continue; this interim data may not be indicative of later or final data for this trial. Forward-looking statements contained in this announcement are made as of this date, and the Company undertakes no duty to update such information except as required under applicable law.

Investor Contact:
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Jenene Thomas
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