A promising antibody treatment for COVID-19, pemivibart, shows strong potential for combating evolving viral variants, according to new research. While failing to secure FDA authorization for treating acute COVID-19, the antibody’s efficacy against dominant strains like JN.1 and KP.3.1.1 was evaluated using immunobridging methods. This approach, often used in vaccine development, assesses antibody effectiveness by comparing neutralizing titers to established treatments.
The core question: Can a new antibody treatment effectively fight off emerging COVID-19 variants?
New antibody shows robust neutralization against key COVID-19 variants
Researchers employed three methods to gauge pemivibart’s ability to neutralize four significant COVID-19 variants: JN.1, KP.3.1.1, XEC, and LP.8.1. The study aimed to provide a pathway for accelerating novel COVID-19 treatments amidst a constantly changing viral landscape.
Bridging the Gap with Immunobridging
Pemivibart demonstrated a consistent “immunobridging” to its parent molecule, adintrevimab, for periods ranging from 4 to over 14 days, depending on the specific variant. This suggests a strong correlation between the antibody’s performance and established benchmarks.
When compared to sotrovimab, another antibody treatment, pemivibart’s neutralizing titers across the tested variants were 4 to 12 times higher. However, over a 14-day analysis, its titers were found to be lower than those of other historical intravenous (IV) administered antibodies.
A dose-response analysis, drawing from a published meta-analysis, predicted pemivibart to have equivalent efficacy to all other comparator antibodies. This indicates that while its initial potency might differ, its overall effectiveness could be on par.
Addressing Unmet Needs
The research highlights the urgent need for effective treatments for immunocompromised individuals. These patients often remain vulnerable despite vaccination and existing antiviral therapies. Pemivibart’s evaluation for acute COVID-19 treatment was driven by this critical unmet need.
The immunobridging framework, previously used to support the Emergency Use Authorization (EUA) of pemivibart for preventing COVID-19 in immunocompromised patients, was adapted for treatment evaluation. This methodological approach, combining quantitative virology and biological mechanisms, offers a blueprint for future drug development.
- Pemivibart demonstrated effective neutralization against key COVID-19 variants JN.1 and KP.3.1.1.
- The antibody showed strong immunobridging to its parent molecule, adintrevimab.
- Neutralizing titers were higher than sotrovimab but lower than other historical IV mAbs.
- Dose-response analysis predicted pemivibart to have equivalent efficacy to comparator antibodies.
- The findings could accelerate the development of new COVID-19 treatments for vulnerable populations.
Clinical Trial Information
The research is associated with Clinical Trial ID: Nct06039449.
Author and Funding Declarations
The authors were employees or contractors of Invivyd, Inc. at the time of the research and may hold stock or shares in the company. The work was supported by Invivyd, Inc. Ethical approval was obtained from Advarra central IRB, and all necessary patient consents were secured and archived.
Data Availability
All data generated in this study are available upon reasonable request to the authors.
