Double Blind, Placebo Controlled Study of Safety and Efficacy of Leronlimab in Patients With "Long" COVID-19

This is a Phase 2, two-arm, randomized, double blind, placebo controlled multicenter study to evaluate the safety and efficacy of leronlimab (PRO 140) in patients with prolonged symptoms caused by Coronavirus Disease 2019 (COVID-19). Patients will be randomized to receive weekly doses of 700 mg leronlimab (PRO 140), or placebo. Leronlimab (PRO 140) and placebo will be administered via subcutaneous injection. The study will have three phases: Screening Period, Treatment Period, and Follow-Up Period. Total study duration is 91 days. The study will be conducted at up to 5 centers in the United States and planned number of subjects are 50 subjects. Visit schedule: Visit 1 - Screening assessment Visit 2 - baseline, first dose Visit 3 - no dose, baseline+3 days Visit 4 - second dose, baseline + 7 days Visit 5 - no dose, safety assessment/con med, baseline +10 days Visit 6 - third dose, baselines + 14 days Visit 7 - no dose, safety assessments, baseline + 17 days Visit 8 - fourth dose, baseline +21 days Visit 9 - no dose, safety assessment, baseline + 24 days Visit 10 - fifth dose, baseline + 28 days Visit 11 - no dose, safety assessment, baseline + 31 days Visit 12 - sixth dose, baseline + 35 days Visit 13 - no dose, safety assessment, baseline + 38 days Visit 14 - seventh dose, baseline + 42 days Visit 15 - no dose, safety assessment, baseline + 45 days Visit 16 - eighth and final dose, baseline + 49 days Visit 17 - End of treatment, baseline + 56 days