The ongoing need for effective treatments against viral infections, such as COVID-19, remains a significant focus in public health. While vaccination efforts have played a substantial role in mitigating the impact of these illnesses, therapeutic interventions continue to be developed and refined. These treatments aim to reduce disease severity, prevent hospitalizations, and improve patient outcomes. Understanding the various approaches available, including specific therapies like antibody infusions, provides valuable insight into the evolving strategies for managing infectious diseases.
How Antibody Infusions Work
Antibody infusions use laboratory-made proteins called monoclonal antibodies, designed to mimic the body’s natural antibodies. These specialized proteins are manufactured using DNA recombinant technology to target the SARS-CoV-2 virus.
Most COVID-19 monoclonal antibodies bind to the spike protein on the virus’s surface. This prevents the virus from attaching to and entering human cells by blocking its interaction with ACE2 receptors. This action neutralizes the virus, impeding infection and reducing viral replication.
Some monoclonal antibodies also activate additional immune responses, like antibody-dependent cellular cytotoxicity (ADCC), which helps destroy infected cells. This multi-pronged approach reduces viral load and lessens disease severity.
Who Qualifies for Treatment
Antibody infusion treatments are for individuals with mild-to-moderate COVID-19 who are at elevated risk of progressing to severe illness, hospitalization, or death. This therapy is not for patients already hospitalized or requiring oxygen for their infection. Early administration is crucial, ideally within seven to ten days of symptom onset or a positive COVID-19 test.
High-risk factors include advanced age (65 years and older), a body mass index (BMI) over 25 or 30, Type 1 or Type 2 diabetes, and chronic kidney or liver disease.
Other risk factors include chronic lung diseases (e.g., asthma, COPD), heart conditions, a weakened immune system due to medical conditions or immunosuppressive medications, and pregnancy.
What to Expect After Infusion
The primary goal of antibody infusion is to reduce the progression of COVID-19 to severe illness, hospitalization, or death. Early intervention, especially with mild-to-moderate symptoms, prevents the virus from overwhelming the body.
It lowers the viral load, mitigating symptom escalation and promoting recovery. The treatment provides ready-made antibodies, offering immediate immune support.
Antibody infusions are delivered intravenously (IV) by a healthcare professional. The infusion typically lasts about one hour, followed by an hour of medical observation for any immediate reactions.
While generally well-tolerated, mild and temporary side effects can occur. These may include infusion-related reactions such as fever, chills, body aches, nausea, vomiting, dizziness, headache, itching, rash, or fatigue. Medical staff are prepared to address any reactions promptly. Patients are typically advised to continue isolating as per public health guidelines even after receiving the infusion.
Current Role in COVID Care
The role of monoclonal antibody infusions in COVID-19 management has evolved. Initially, they were a primary outpatient treatment for high-risk individuals. However, new SARS-CoV-2 variants, particularly Omicron, significantly impacted the effectiveness of many original therapies, as mutations in the viral spike protein often rendered earlier antibody treatments less capable or entirely ineffective at neutralizing circulating strains.
This led to the deauthorization of several monoclonal antibody products. The landscape of COVID-19 therapeutics has diversified, with oral antiviral medications like Paxlovid and molnupiravir now often preferred for outpatient treatment of mild-to-moderate COVID-19 in eligible high-risk patients. These antivirals work by inhibiting viral replication and have largely maintained their effectiveness against newer variants.
Despite these changes, monoclonal antibodies still have a place in COVID-19 treatment. Some, like tocilizumab, are used in hospitalized patients with severe COVID-19 to manage inflammatory responses, not to directly target the virus.
For certain immunocompromised individuals who may not respond to vaccination, long-acting monoclonal antibodies have been explored for pre-exposure prophylaxis, offering a temporary shield against infection.
Antibody infusions treat existing infection or provide prophylaxis in specific cases. They are not a substitute for vaccination, which remains the most effective method for preventing COVID-19 and its severe outcomes.