 ROCKVILLE, Md., July 22, 2021 PRNewswire -- RegeneRx Biopharmaceuticals, Inc. OTCQB: RGRX the Company or RegeneRx, a clinical-stage drug development company focused on tissue protection, repair and regeneration, has issued a Letter to Stockholders updating its recent financing, the FDA regulatory process for RGN-259, and its 12-month operating strategy. 