Rein Therapeutics Announces Closing of $57.5 Million Underwritten Public Offering, Including Full Exercise of Over-Allotment Option

Offering oversubscribed through full exercise of underwriters' option, supported by strong investor demand

• Total gross proceeds increased to $57.5 million
• Offering consisted solely of common stock
• Proceeds expected to fund Phase 2 trial of LTI-03 in IPF through completion and support operations into 2028
  
  

AUSTIN, Texas, May 18, 2026 (GLOBE NEWSWIRE) -- Rein Therapeutics, Inc. ("Rein" or the "Company") (NASDAQ: RNTX), a clinical-stage biopharmaceutical company advancing a novel pipeline of first-in-class medicines for orphan pulmonary and fibrosis indications, today announced the closing of its previously announced underwritten public offering of common stock, including the full exercise of the underwriters' over-allotment option. The financing included new and existing healthcare-focused investors, including Adar1 Capital Management LLC, Ikarian Capital LLC, Bios Partners, Stonepine Capital Management, Cable Car Capital LP, and Second Line Capital.

In total, 57.5 million shares were sold at $1.00 per share, resulting in aggregate gross proceeds of $57.5 million, before deducting underwriting discounts and commissions and other expenses.

The transaction included the full exercise of the underwriters' option to purchase an additional 7.5 million shares of common stock to cover over-allotments.

No warrants or other derivative securities were issued to the investors in connection with the financing.

Brian Windsor, Ph.D., Chief Executive Officer of Rein Therapeutics, commented, "We are pleased to have successfully completed this offering, including the full exercise of the over-allotment option. We appreciate the support from both new and existing investors as we continue to advance our Phase 2 RENEW trial of LTI-03 in IPF. This financing strengthens our balance sheet and positions us to execute on our clinical and operational priorities."

Rein intends to use the net proceeds from the offering to:

• Fully fund its ongoing Phase 2 clinical trial of LTI-03 in idiopathic pulmonary fibrosis (IPF) through completion;
• Support continued clinical development, manufacturing, and regulatory activities; and
• Fund working capital and general corporate purposes.
  
  

Based on its current operating plan, the Company believes the net proceeds from this offering, together with its existing cash and cash equivalents, will be sufficient to fund its operations into the first quarter of 2028.

Offering Details

The securities described above were offered and sold pursuant to a registration statement on Form S-1 (File No. 333-295390), including a prospectus, filed with the U.S. Securities and Exchange Commission (the "SEC"), which was declared effective by the SEC on April 30, 2026.

The offering was made only by means of a prospectus. A final prospectus relating to the offering has been filed with the SEC and is available on the SEC's website at http://www.sec.gov. Copies of the final prospectus may be obtained from Konik Capital Partners, LLC, a division of T.R. Winston & Company, LLC, at 7 World Trade Center, 46th Floor, New York, NY 10007, Attention: Capital Markets Team, Email: [email protected].

This press release shall not constitute an offer to sell or the solicitation of an offer to buy any of the securities described herein, nor shall there be any sale of these securities in any state or jurisdiction in which such offer, solicitation or sale would be unlawful.

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. 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.

Cautionary Note Regarding 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 and LTI-01 product candidates and the closing of the offering. 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, including: (i) the risk that the net proceeds of the offering may not be sufficient to fully fund the Company's ongoing Phase 2 clinical trial of LTI-03 through completion or fund the Company's operations into 2028, and (ii) those other risks disclosed in the "Risk Factors" section of the Company's Annual Report on Form 10-K for the year ended December 31, 2025 filed with the SEC on March 26, 2026, and in subsequent filings that the Company makes with the SEC. These forward-looking statements should not be relied upon as representing the Company's views as of any date after the date of this press release, and the Company expressly disclaims any obligation to update any forward-looking statements, whether as a result of new information, future events or otherwise, except as required by law.

Rein Therapeutics Investor Relations & Media Contact:

Investor Relations

[email protected]