Revive Therapeutics Ltd. announced that it has submitted a Type C meeting request package to the U.S. Food & Drug Administration ("FDA") for the evaluation of a proposed clinical study of Bucillamine, an oral thiol-based drug with anti-inflammatory and antiviral properties, as a potential treatment for long-term COVID. Following the submission of the Type C meeting request package, the Company expects to hear from the FDA on a firm date for the meeting. Currently, the Company is exploring the use of Bucillamine as a potential treatment for long COVID.

The Company is advancing the clinical development of Bucillamine by leveraging the published research and data from its previous Phase 3 clinical trial (the "Study") and is finalizing the regulatory and clinical package that includes a proposed clinical study for long COVID to present to the FDA. On July 6, 2023, the Company announced the results of its Study evaluating the safety and efficacy of oral Bucillamine in patients with mild to moderate COVID-19. Under the Study?s primary endpoint, the proportion of patients meeting a composite endpoint of hospitalization or death from time of first dose through Day 28 following randomization, there were no deaths and four hospitalizations, of which three were from the placebo arm and one from the Bucillamine low dose group (300mg/day).

No hospitalizations occurred in the Bucillamine large dose group (600mg/day). The Company evaluated certain Study endpoints, including the COVID-19 clinical symptoms data (icough, fever, heart rate, and oxygen saturation). Based on preliminary analyses, the data demonstrated that for patients with oxygen saturation <96% at baseline, Bucillamine had a 29.1% improvement over placebo in time to normal oxygen saturation (SpO2).

Additional analyses of the Study data may suggest Bucillamine?s potential for long COVID. A study titled ?Thiol-based drugs decrease binding of SARS-CoV-2 spike protein to its receptor and inhibit SARS-CoV-2 cell entry? showed that thiol-based drugs, like Bucillamine, decrease the binding of SARS-CoV-2 spike protein to its receptor, decrease the entry efficiency of SARS-CoV-2 spike pseudotyped virus, and inhibit SARS-CoV-2 live virus infection.

These findings uncovered a vulnerability of SARS-CoV-2 to thiol-based drugs and provided a rationale to test thiol-based drugs such as Bucillamine as novel treatments for COVID-19.