According to a recent study published in the Annals of Internal Medicine, the levels of SARS-CoV-2 antigen in the blood of hospitalised COVID-19 patients seem to correlate with the severity of the disease and other clinical outcomes.
Antibodies are produced by your immune system in response to antigens, which are substances that are outside of your body. The COVID-causing virus SARS-CoV-2 contains antigens.
According to the study’s authors, higher antigen levels could indicate that the virus is reproducing and the condition is getting worse. As a result, antigen levels might be utilised to forecast who patients may be at a higher risk of developing COVID-19 that is more severe as well as who might benefit from specific treatments.
According to the study’s findings, “a considerable number of patients hospitalised with acute SARS-CoV-2 infection may be more likely to benefit from antiviral medication,” which is why inpatient COVID-19 clinical studies need to take a precision medicine approach.
Blood samples from 2,540 hospitalised COVID-19 patients participated in the Therapeutics for Inpatients with COVID-19 trial were examined by scientists from the National Institute of Allergy and Infectious Diseases and many American universities for the presence of virus antigen. Prior to the Omicron variant taking over, they concentrated on individuals who had up to 12 days of symptoms between August 2020 and November 2021.
The blood was tested for a coronavirus-specific antigen, and the patient’s exposure to the Delta variant was also determined. On the fifth day of the clinical trial, they examined the time to hospital discharge and lung-related symptoms.
The study’s investigators discovered a direct correlation between poorer lung function at the time the patient joined in the experiment and coronavirus antigen concentrations of 1,000 nanograms per litre or higher. Regardless of how serious their sickness was when they entered, those with greater antigen levels also typically had lower lung function at day 5. Antigen levels were also greater in patients who had symptoms for longer than a week.
When compared to people breathing room air, average antigen levels were three times greater in people who required noninvasive ventilation or oxygen. By day 5, 26% of patients with antigen concentrations of 1,000 nanograms per litre or higher required oxygen, compared to 6% of patients with antigen concentrations of 1,000 nanograms per litre or lower.
Longer hospital stays were associated with patients who had greater antigen levels. They spent an average of seven days in the hospital, as opposed to four days for those with lower antigen levels. By day 28, about 42% of patients receiving ventilation or oxygen had been discharged, compared to 73% of patients with low antigen levels.
Antigen levels found to be related to a number of risk factors. High antigen levels and poorer outcomes were more prevalent in men and individuals over 65. Additionally, individuals who contracted the Delta variation had higher amounts of antigen than patients who contracted the variants that predominated before Delta.
Antigen levels were more likely to be lower in patients who had coronavirus antibodies from vaccination or a prior illness as well as those who had taken the antiviral drug remdesivir for two or more days.