By: Fern Sidman
After pausing distribution last month to conserve supply, the Department of Health and Human Services is now shipping 55,000 doses of the monoclonal antibody drug, called Sotrovimab, to state health departments to stop the increasing spread of the highly transmissible Omicron variant of the coronavirus. An additional 300,000 doses are expected in January, as was reported by the AP.
Sotrovimab is an investigational SARS-CoV-2 neutralizing monoclonal antibody. The antibody binds to an epitope on SARS-CoV-2 shared with SARS-CoV-1 (the virus that causes SARS), indicating that the epitope is highly conserved, which may make it more difficult for resistance to develop. Sotrovimab, which incorporates Xencor, Inc.’s Xtend™ technology, has also been designed to achieve high concentration in the lungs to ensure optimal penetration into airway tissues affected by SARS-CoV-2 and to have an extended half-life.
The Department of Health and Human Services (HHS) said it is distributing Sotrovimab to states based on their levels of infections and hospitalizations.
Developed by British drugmaker GlaxoSmithKline with Vir Biotechnology, the AP reported that Sotrovimab was specifically formulated to bind to a part of the virus that is less likely to mutate, according to the companies. Early studies of laboratory-simulated omicron by the drugmakers and outside researchers show promising results.
Supply of the drug, Sotrovimab, is “extremely limited, and additional doses of the product will not be available until the week of January 3rd,” the Department of Health and Human Services said in a statement posted online, as was reported by the AP.
The Secretary of the Department of Health and Human Services has declared a public health emergency that justifies the emergency use of drugs and biological products during the COVID-19 pandemic. In response, the FDA has issued this EUA, as requested by GlaxoSmithKline, for Sotrovimab, for the treatment of mild-to-moderate COVID-19 in adults and pediatric patients (12 years of age and older weighing at least 40 kg) with positive results of direct SARS-CoV-2 viral testing, and who are at high risk for progression to severe COVID-19, including hospitalization or death.
According to a December 27th report in the Texas Tribune, the state’s health services department is warning that “five of its regional infusion centers have run out of the only monoclonal antibody treatment known to be effective against the omicron variant of COVID-19, which now accounts for 90% of new cases in the state.”
The Texas Tribune also reported that the Texas Department of State Health Services says its regional infusion centers in Austin, El Paso, Fort Worth, San Antonio and The Woodlands “have exhausted their supply of Sotrovimab,” the only monoclonal antibody treatment that appears to be effective against the omicron variant. The department said the scarcity stems from a national shortage of the treatment, which is made by GlaxoSmithKline and received emergency use authorization from the U.S. Food and Drug Administration in May.
The AP reported that the HHS recommends states conserve the drug for the highest risk patients who are most likely to have omicron infections, either based on laboratory testing that can identify the variant or elevated levels of omicron spread in local communities, identified as 20% and higher.
High-risk patients include seniors and those with serious health problems, such as obesity, heart disease, diabetes and immune-system disorders.
Dr. Jonathan Li, director of the Harvard/Brigham Virology Specialty Laboratory told the AP: “I think there’s going to be a shortage. We’re down to one FDA-authorized monoclonal antibody with omicron because of the reduced effectiveness of Regeneron and Lilly’s drugs.”
The AP reported that prior to the pause in shipments, Glaxo’s drug, Sotrovimab, accounted for about 10% of the 1.8 million antibody doses distributed to state health officials between mid-September and late November, according to federal figures.
Delivered by injection or infusion, antibodies are laboratory-made versions of human proteins that help the immune system fight off viruses and other infections, as was reported by the AP.
According to a statement published on their web site, the National Institute for Health (NIH) stated that: “The Omicron variant, which includes numerous mutations in the spike protein, is predicted to have markedly reduced susceptibility to several anti-SARS-CoV-2 monoclonal antibodies (mAbs), especially bamlanivimab plus etesevimab and casirivimab plus imdevimab. Sotrovimab appears to retain activity against the Omicron variant.”
George Scangos, PhD, Chief Executive Officer of Vir Biotechnology said: “Sotrovimab is the first monoclonal antibody to report preclinical data demonstrating activity against all tested SARS-CoV-2 variants of concern and interest to date, including Omicron, as well as the still prevalent and highly contagious Delta variant. Given the less than three-fold neutralization shift demonstrated in the pre-clinical pseudo-virus assay, which falls below the FDA authorized fact sheet guidance of less than a 5-fold change, we are confident that Sotrovimab will continue to provide significant benefit for the early treatment of patients hoping to avoid the most severe consequences of COVID-19.”
Dr Hal Barron, Chief Scientific Officer and President of Research and Development at GlaxoSmithKline said: “From the outset of our collaboration with Vir Biotechology we hypothesized that Sotrovimab would have a high barrier to resistance and thus could deliver best-in-class potential for the early treatment of patients with COVID-19. These pre-clinical data demonstrate the potential for our monoclonal antibody to be effective against the latest variant, Omicron, plus all other variants of concern defined to date by the World Health Organization, and we look forward to discussing these results with regulatory authorities around the world.”