Scientists in the UK have just recruited the world’s first participants to be part of a new long-term antibody study.
If treatment is effective, it could provide protection against the development of COVID-19 to those who have already been exposed to SARS-CoV-2.
“We know that this combination of antibodies can neutralize the virus,” explains veterinarian Catherine Houlihan of University College London Hospitals (UCLH).
“Therefore, we hope to find that giving this treatment by injection can lead to immediate protection against the development of COVID-19 in people who have been exposed, when it would be too late to offer a vaccine.”
This may not be the first antibody treatment against COVID-19 you’ve heard of. Outgoing US President Donald Trump was given monoclonal antibodies when he fell ill with the disease, and in the United States, two different antibody treatments (casirivimab and imdevimab) received emergency approval in November.
But these antibody treatments are given to patients with mild to moderate COVID-19, who are at risk of progressing to a severe version of the disease.
“In a clinical trial of patients with COVID-19, it was shown that casirivimab and imdevimab, co-administered, reduce hospitalizations or emergency room visits related to COVID-19 in patients at high risk of disease progression within 28 days after treatment compared to placebo, “the FDA said in a press release when the drugs were approved.
This new antibody therapy, called AZD7442 and developed by UCLH and AstraZeneca, is a little different.
AZD7442 is a combination of two monoclonal antibodies AZD8895 and AZD1061, which target the SARS-CoV-2 spike protein receptor binding domain.
“By targeting this region of the virus ear protein, antibodies can block the virus from attaching to human cells and therefore are expected to block the infection,” the team wrote on the site U.S. ClinicalTrials.gov website.
“Amino acid substitutions have been introduced into antibodies to prolong their half-life, which should prolong their potential prophylactic benefit and decrease Fc effector function to decrease the potential risk of improving antibody-dependent disease.”
Antibodies are small Y-shaped proteins that bind to a certain section (called an antigen) of a virus, bacterium, or other pathogen and either label it to be attacked by the immune system or directly block it. pathogen that invades our cells.
The body produces normal antibodies after an infection, while monoclonal antibodies are cloned in a laboratory and can be injected into an already infected person to help the immune system.
The researchers hope that AZD7442, which is just starting the Storm Chaser study (the name of its phase 3 trial), will provide protection to those who have been exposed to the virus but are not yet showing symptoms. Indeed, they are trying to prevent COVID-19 from happening in the first place.
“If you have outbreak problems in settings such as nursing homes or if you have patients who are at risk for severe COVID, such as the elderly, this can save many lives,” University of East Anglia said Paul Hunter, expert in infectious diseases The guardian.
“If you live with your grandma and you or someone in the house gets infected, you could give her that to protect her.”
But they also expect it to be effective in the long term, over a period of 6 to 12 months, which means people who cannot get the vaccine for medical reasons have another option to stay protected from the disease.
Researchers are studying how this might work for people with compromised immune systems in a second trial called PROVENT.
“We will recruit people who are older or in long-term care and who have conditions such as cancer and HIV that may affect their immune system’s ability to respond to a vaccine,” said Nicky Longley, an infectious disease consultant at the UCLH. The guardian.
“We want to reassure anyone for whom a vaccine may not work that we can offer an equally protective alternative.”
We’re looking forward to seeing where this leads.