New Antibody Offers Enhanced Protection Against Covid-19

A novel antibody known as Sipavibart has emerged as a promising option for the prevention of Covid-19, demonstrating a significant reduction in risk for vulnerable populations. This antibody works by binding to the receptor binding domain of the SARS-CoV-2 virus, effectively blocking its access to human cells.

Throughout the pandemic, monoclonal antibodies have been utilized for the treatment and prevention of Covid-19. One such example is Evusheld®, which contains the antibodies Tixagevimab and Cilgavimab. However, the Standing Committee on Vaccination (STIKO) in Germany has recently limited the use of Evusheld for pre-exposure prophylaxis (PrEP) to specific cases, citing a decline in its effectiveness.

Sipavibart, marketed as Kavigale® (300 mg injection/infusion solution by AstraZeneca), boasts a broader neutralizing capacity against various SARS-CoV-2 variants, including XBB.1 and BA.2.75. Nevertheless, it is important to note that Sipavibart may not offer protection against symptomatic Covid-19 caused by variants containing the F456L mutation in the spike protein, a mutation present in many currently circulating strains.

The mechanism of action for Sipavibart is similar to other neutralizing antibodies, relying on its ability to bind to the receptor binding domain of the spike protein. This binding action prevents the virus from interacting with the human ACE-2 receptor, thus inhibiting its entry into host cells.

Sipavibart is approved for use in adults and adolescents over the age of twelve, with a minimum weight of 40 kg, who are immunocompromised due to certain medical conditions or treatments. The recommended dosage is 300 mg, administered either via intramuscular injection or intravenous infusion, providing protection for at least six months. Patients can receive additional doses every six months if necessary.

It is crucial for patients to be informed that breakthrough infections can still occur. They are advised to seek medical attention immediately if they experience symptoms such as breathing difficulties, fever, chills, cough, fatigue, or a sudden loss of taste or smell.

Infusion-related reactions may occur with intravenous administration of Kavigale. In such cases, healthcare providers are instructed to pause, slow down, or discontinue the infusion and initiate appropriate medical treatments. Caution is also advised when administering Sipavibart to patients with thrombocytopenia or other bleeding disorders.

During pregnancy, the use of Sipavibart should be considered only if the potential benefits to the mother outweigh the risks to the fetus. As for breastfeeding, IgG antibodies can be transferred into breast milk shortly after birth, although their concentration diminishes quickly. Therefore, while there may be a risk to the nursing infant during this short period, Sipavibart may be utilized during breastfeeding when clinically indicated.