Inclusion Criteria:  Participant is ≥ 18 years of age. Positive result of a SARS CoV-2 RNA diagnostic test result ≤48 hours before enrollment, warranting hospital admission as per Investigator's judgement. COVID-19 pneumonia findings on imaging (chest X-ray or CT Scan). Requires oxygen supplementation with FIO2 approximately 30% or greater administered by nasal cannula, mask, or NIV. Participants can be on other medication on-label to treat COVID-19 respiratory disease that the Investigator deems clinically relevant in combination with the study drug, including corticosteroids. Passage of 24 hours after administration of the EUA drug will be required prior to dosing GIGA-2050. Men or non-lactating female participants who are surgically sterile or post-menopausal, or a Woman of Childbearing Potential (WCBP) with a negative pregnancy test at screening willing to use highly effective contraception methods.  Exclusion Criteria:  Acute respiratory failure requiring invasive mechanical ventilation or ECMO at enrollment. Systolic Blood Pressure (SBP) <110 mmHg or heart rate >120 bpm. Pre-existing heart failure or unstable angina or myocardial infarction in the last month prior to screening. Pre-existing chronic respiratory condition(s). Evidence of acute kidney injury, increase of serum creatinine of ≥1.5 x baseline, or urine output of <0.5mL/kg/hr sustained for at least 6 hours once volume repleted. Aspartate aminotransferase (AST) ≥2.5 x ULN, alanine aminotransferase (ALT) ≥2.5 x ULN, and/or total bilirubin >1.5 x ULN, or severe hepatic impairment. Known systemic hypersensitivity to recombinant antibody therapies. Female participant who is pregnant. Participant is expected to transfer to a non-investigative facility from the investigation site and cannot be monitored for compliance with protocol-required safety monitoring procedures. Participants who are currently participating or have participated in another clinical trial within 30 days prior to screening.