Although COVID-19 is mainly a respiratory disease it can cause substantial morbidity and mortality. The natural history of COVID-19 suggests that initiating therapy early in the infection may reduce the risk of the disease progressing to more severe disease, hospitalization and death. Potential therapeutic strategies involve the use of agents to dampen down the systemic inflammation the virus causes. The study will investigate whether a passive immunotherapy strategy of hyperimmune intravenous immunoglobulin (hIVIG) will reduce the risk of disease progression when given to adults with early COVID-19 infection.
The study will compare the efficacy and safety of a single infusion of anti-coronavirus hIVIG given with standard of care treatment versus placebo plus standard of care treatment in adults recently diagnosed with COVID-19 who do not require hospitalisation. The hIVIG that will be used is obtained from donations from people recovered from COVID-19 and have been vaccinated. It contains antibodies that bind to SARS-CoV-2, the virus that causes COVID-19, and prevent it from replicating and causing severe infection. As currently available COVID-19 therapies have a different mechanism of action to hIVIG, combining the treatment strategies may provide additional benefits.
This randomised placebo-controlled study will recruit adult outpatients recently diagnosed with COVID-19 infection at clinic sites in North and South America, Europe, Australia, Africa and Asia. Participants will be randomly assigned to receive either a single infusion of anti-coronavirus hIVIG or placebo in addition to local standard of care COVID-19 therapy. Participants will remain on study for 28 days during which time they will be assessed for clinical, laboratory and virological outcomes, adverse events, hospitalisation and survival.
The OTAC study completed enrolment with 741 participants and concluded in May 2026. The trial was stopped early following a futility assessment, with no safety concerns identified. Final analyses are in progress and study results will be reported in future scientific publications.
The OTAC study provides important evidence for clinicians, researchers and policymakers evaluating passive immunotherapy approaches for COVID-19. Although the trial was stopped early following a futility assessment, the study generated valuable safety and clinical outcome data from 741 participants enrolled across an international network of sites. These findings will contribute to the evidence base for COVID-19 therapeutics and help guide future pandemic preparedness and infectious disease research.
- University of Minnesota MN
- International Coordinating Centers (ICCs) of the INSIGHT Network:
- Copenhagen HIV Programme (CHIP) - Copenhagen, Denmark
- Medical Research Council (MRC) Clinical Trials Unit at University College London (UCL) -London, United Kingdom
- The Kirby Institute, University of New South Wales - Sydney, Australia
- The Institute for Clinical Research at the Veterans Affairs Medical Center - Washington, D.C., USA
- US Department of Veterans Affairs, USA
- Division of Clinical Research (DCR) National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH) – Bethesda, MD, USA
- Hennepin Medical Center - Minneapolis, Minnesota, USA
National Institute of Allergy and Infectious Diseases (NIAID),
National Institutes of Health (NIH)
