Ever since the Ex-President of the US Mr. Donald Trump recovered from Coronavirus by receiving a combination of two antibodies intravenously in October 2020 and recovered completely, the monoclonal antibodies have gained global attention. A few days ago, an elderly Indian too recovered successfully from a coronavirus infection after receiving this therapy.
What is the cocktail at a combined dose of 1200 about?
This is a combination of two antibodies, casirivimab, and imdevunab. It is to be used for the treatment of Covid-19 infected individuals. This is recommended only for mild to moderately ill and high-risk patients. This may cost up to 235000 for each individual.
What are casirivimab and imdevimab?
Casirivimab and imdevimab are monoclonal antibodies that mimic the immune system that produce antibodies against the coronavirus in the human body. These two antibodies are produced in the laboratory. They specifically target the spike proteins of the SARS-CoV-2 virus. Thus they block the attachment of the virus to the human cells. This prevents the virus from getting into the human cells.
Are these antibodies effective against the new emerging variants of the virus?
These monoclonal antibodies attach themselves to different parts of the virus. This helps the anti-bodies to be effective against the variants of the virus. This also helps to reduce its neutralising capacity against new emerging variants.
For whom it is used?
It is used in adults and in children above 12 years. It is to be used only for high-risk individuals. It is used mg once only. What is the evidence for the efficacy of this cock-tail of antibodies in coronavirus infection? The drug was tried in 4500 non-hospitalized individuals with coronavirus infection. It showed that the cocktail reduced the incidence of death or hospitalization by 70% as compared to a placebo. Caserivimab and imdevimab also significantly shortened the duration of symptoms by 4 days. The drug is only for those who are not hospitalized. Once hospitalized the individual would require Remdesivir and steroids like dexamethasone.
Who are the high-risk individuals who are considered for monoclonal antibodies therapy?
These are individuals with obesity and BMI above 35. They are recommended for those with chronic kidney disease, diabetes, immunosuppressive therapies, or those immunosuppressive diseases. It is recommended for those above 65 years and those above 55 years and who have cardiovascular disease or hypertension or with chronic obstructive airway disease. Patients with multiple risk factors are at the greatest risk.
Are there any adverse effects of this drug?
Mild symptoms like headache, body ache, and fever have been noted. Nausea, rash, and itching have been noted too. In the drug trials, some individuals did have moderate hypersensitivity reactions. The infusion has to be monitored carefully. The health authorities in many countries do not authorize the use of these antibodies in individuals on oxygen therapies or those with severe disease as the results of these monoclonal antibodies in these individuals were not satisfactory.
Can these antibodies be administered in pregnancy!?
These IgG monoclonal antibodies are expected to cross the placenta. There is no robust data on this aspect so far. However, if the care provider and the patient consider that the benefits outweigh the risks of therapy, then it should be used to prevent the worsening of the disease.
What about vaccination in individuals who have received these monoclonal antibodies as therapies for coronavirus infection?
The vaccination should be deferred by 90 days. This is to prevent interference of antibody formation by vaccination because of previous monoclonal anti-bodies therapy.
Monoclonal antibodies are therapies for non-hospitalized individuals and those with a high risk of getting a serious infection. These may be a game-changer in coronavirus infections in selected individuals. However, the accepted Covid behavior that includes the use of two masks, social distancing, and vaccination should not be ignored.
