RegeneRx Licensee Submits Special Protocol Assessment to FDA for 4th Phase 3 Clinical Trial for Dry Eye Disease

Expect ARISE-4 Trial to Begin Around 2^nd Quarter of 2023

ROCKVILLE, Md., Oct. 24, 2022 /PRNewswire/ -- RegeneRx Biopharmaceuticals, Inc. (OTCQB: RGRX) ("RegeneRx" or "Company"), a clinical-stage drug development company focused on tissue protection, repair, and regeneration, is reporting today that its U.S. joint venture (JV) partner and licensee, HLB Therapeutics (HLBT), has announced that it submitted a request for the Special Protocol Assessment (SPA) to the U.S. FDA for an in-depth discussion and assessment of the clinical protocol for a fourth phase 3 clinical trial (ARISE-4) for the treatment of dry eye disease. RGN-259 is a sterile, preservative-free, eyedrop being developed by ReGenTree, a U.S. joint venture company between RegeneRx Biopharmaceuticals and HLB Therapeutics.

"In accordance with our SPA request, we have submitted to the FDA a briefing document summarizing our ARISE-1, -2, and -3 clinical data, including efficacy parameters and questions related to the clinical development of RGN-259 dry eye, along with the ARISE-4 protocol and statistical analysis plan. It is expected that the detailed direction and agreement given by FDA in advance by using the SPA process will help the company's development strategy for the approval of RGN-259. Considering the initiation of this process, we expect that the ARISE-4 trial will begin around the second quarter of 2023," according to HLB Therapeutics.

SPA is a process by which sponsors may request to meet with FDA to reach agreement on the design and size of certain trials, clinical studies, or animal studies to determine if they adequately address scientific and regulatory requirements for a study that could support marketing approval. After completing the SPA review, FDA issues a letter including comments from the review team, agreement or nonagreement with the proposed protocol, and answers to the sponsor's relevant questions. According to FDA guidance, the official period for SPA review is 45 days.

RGN-259 is a sterile, preservative-free, eye drop developed to reduce damage and improve healing for various ophthalmic indications including dry eye syndrome and neurotrophic keratopathy.  To date, over 1700 subjects have received RGN-259 indicating various degrees of efficacy in both DED and NK.  RGN-259 has shown to be quick-acting, well-tolerated and does not have the documented side effects of other approved pharmaceutical products for these indications. Thymosin beta 4, the active pharmaceutical ingredient of RGN-259, that has demonstrated various mechanisms of action, including promotion of cell migration, cytoprotection, wound healing, and anti-inflammatory properties.

Any statements in this press release that are not historical facts are forward-looking statements made under the provisions of the Private Securities Litigation Reform Act of 1995. Any forward-looking statements involve risks and uncertainties that could cause actual results to be materially different from historical results or from any future results expressed or implied by such forward-looking statements. Forward-looking statements in this press release include but are not limited to statements from us, our partners, or within research published by third parties. There can be no assurance of the timing of any clinical trials or that positive results from any research or clinical trial by the Company, its collaborators, or independent parties in the U.S. or any other country will result in subsequent clinical confirmation or future value. There can also be no assurance that any of the Company's drug candidates will result in any approved products in the U.S. or any other country. Please view risks described in the Company's filings with the Securities and Exchange Commission ("SEC"), including those identified in the "Risk Factors" section of the annual report on Form 10-K for the year ended December 31, 2021, and subsequent quarterly reports filed on Form 10-Q, as well as other filings it makes with the SEC. Any forward-looking statements in this press release represent the Company's views only as of the date of this release and should not be relied upon as representing its views as of any subsequent date. The Company specifically disclaims any obligation to update this information, as a result of future events or otherwise, except as required by applicable law.

SOURCE RegeneRx Biopharmaceuticals, Inc.