RLF-100 (aviptadil) is a synthetic form of Vasoactive Intestinal Polypeptide (VIP), a ubiquitous, naturally synthesized human peptide with extensively documented antiinflammatory, anti-cytokine cascade properties. It has been granted FDA Fast Track Designation for treatment of Critical COVID-19 with Respiratory Failure. A phase 2/3 trial is underway that has passed its first evaluation at 30 patients for safety and futility. This expanded access protocol is designed to offer access to investigational use of RLF-100 to patients who do not qualify for inclusion in Protocol RLF-100-001 (NCT04311697) either on the basis of specific medical exclusions or because there is no accessible study site available to the prospective participant.