RegeneRx Biopharmaceuticals, Inc. reported 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 developed by ReGenTree, a U.S. joint venture company between RegeneRx Biopharmaceuticals and HLB Therapeutics. In accordance with SPA request have submitted to the FDA a briefing document summarizing 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, 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.