ACTG Adds First Polyclonal Antibody to ACTIV-2 Outpatient Treatment Study for COVID-19

Apr 21, 2021

Newswise — Los Angeles, Calif. – The AIDS Clinical Trials Group (ACTG), the largest global HIV research   network, today announced the addition SAB-185, a polyclonal antibody therapy, to the COVID-19 outpatient treatment study, ACTIV-2 Outpatient Monoclonal Antibodies and Other Therapies Trial. ACTIV-2 includes both phase 2 and phase 3 evaluations of multiple investigational agents for treating early, symptomatic COVID-19 in a single trial. For information about enrolling in the trial, please visit the study website.

“While we are thrilled to see the widescale roll-out of COVID-19 vaccines, we know that prevention and treatment will continue to play important roles in ending this pandemic,” said ACTG Chair Judith Currier, M.D., M.Sc., University of California, Los Angeles (UCLA). “Treatment, even among people who are unlikely to advance to severe disease, can have profound benefits, including shortening the duration of symptoms and potentially reducing or eliminating transmission of SARS-CoV-2 – the virus that causes COVID-19 – to others. By evaluating multiple agents across a single platform, ACTIV-2 aims to identify and advance treatments as expeditiously as possible.”

SAB-185, is the first polyclonal antibody (a treatment containing many different antibodies) to be evaluated in ACTIV-2. SAB-185 is made by cows that have been genetically engineered to make human antibodies. Once the cows developed an immune response and generated antibodies against the spike protein on the surface of SARS-CoV-2, samples of their blood are collected, and the antibodies are separated out and purified. SAB-185 is administered through an intravenous infusion and ACTIV-2 will evaluate two different doses.

ACTIV-2 is a randomized, blinded, controlled adaptive platform that allows promising therapies to be added and removed over the course of the study to efficiently test a variety of new agents against placebo within the same trial infrastructure. In addition to studying the safety and efficacy of investigational therapies, ACTIV-2 also aims to determine whether they can decrease viral shedding, thereby potentially preventing transmission of SARS-CoV-2. Participants who enroll in ACTIV-2 will be randomly assigned to receive SAB-185, another ACTIV-2 agent, or placebo. Other agents currently being evaluated include:

  • AZD7442 (AstraZeneca): a combination of two monoclonal antibodies being studied as both a 15-minute infusion and an intramuscular injection
  • SNG001 (Synairgen): a nebulized formulation of beta interferon being studied as an inhalant
  • Camostat (Sagent Pharmaceuticals): an orally administered serine protease inhibitor
  • BRII-196 and BRII-198 (Brii Biosciences): two separately administered monoclonal antibody infusions

To qualify for ACTIV-2, participants must have tested positive for SARS-CoV-2 in the outpatient setting within 10 days and started experiencing symptoms within eight days of enrolling. Participants eligible for the infusion studies, including SAB-185, will have a risk factor that puts them at higher risk of progressing to severe COVID-19, including being age 60 or older, being a current smoker, or having one of the following conditions: chronic lung, kidney, or liver disease; obesity; hypertension; cardiovascular disease; diabetes; or current cancer or immunosuppression. Participants eligible for the other agents may be at higher or lower risk for progressing to severe COVID-19.

ACTIV-2 is sponsored by the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health (NIH), which also funds the ACTG. ACTIV-2 is part of NIH’s Accelerating COVID-19 Therapeutic Interventions and Vaccines (ACTIV), a public-private partnership program to create a coordinated research strategy that prioritizes and speeds development of the most promising treatments and vaccines. It also receives support from the Federal COVID Response – Therapeutics, the U.S. government’s multi-agency effort to accelerate the development, manufacturing, and distribution of COVID-19 vaccines, therapeutics, and diagnostics.

“While there has been much deserved enthusiasm about monoclonal antibodies, including those we’re studying in ACTIV-2, we are especially eager to evaluate our first polyclonal antibody,” said Babafemi Taiwo, M.B.B.S., Professor of Medicine and Chief of Infectious Diseases at Northwestern University and lead investigator of SAB-185 in ACTIV-2. “Because it contains many different antibodies, SAB-185 is able to simultaneously attack different parts of the viral spike protein in SARS-CoV-2, making it a potentially very promising and effective treatment option.”

ACTIV-2 is led by Kara W. Chew, M.D., M.S., UCLA and Davey Smith, M.D., University of California, San Diego (protocol chairs) and David Alain Wohl, M.D., University of North Carolina (UNC) and Eric S. Daar, M.D., Lundquist Institute at Harbor-UCLA Medical Center (vice-chairs) and supported by Dr. Currier and ACTG Co-Chair Joseph J. Eron, M.D., UNC.


For more information about ACTIV-2, please visit, or


To read the full press release click here.