Invivyd, Inc. announced that PEMGARDA (pemivibart), its investigational monoclonal antibody (mAb), continues to exhibit neutralizing activity against the dominant SARS-CoV-2 variant XEC, according to new in vitro neutralization data. The Centers for Disease Control (CDC) estimates that XEC and KP.3.1.1, another variant previously shown to be susceptible to PEMGARDA, together accounted for 69% of circulating SARS-CoV-2 variants in the U.S. as of December 21, 2024. These findings reinforce pemivibart's potential as a crucial tool for protecting immunocompromised individuals against COVID-19.
The data, generated as part of Invivyd's industrial virology effort, leverage a consistent, high-quality, independent, third-party pseudoviral system. This system routinely tests authentic Invivyd-produced pemivibart and is supported by extensive structure-based and proprietary analytics.
Consistent Neutralization Across Variants
Invivyd has demonstrated PEMGARDA's positive neutralization activity against over 75% of currently circulating U.S. variants and all prior variants tested to date. The company anticipates that every clinical variant reported in the CDC COVID Tracker since the Omicron BA.1 lineage has been susceptible to pemivibart due to the consistent structural integrity of the pemivibart epitope. This suggests that pemivibart's neutralization activity will remain largely unchanged, barring any significant structural alterations to its target epitope.
"We designed pemivibart and our pipeline molecules to resist the effects of evolution," said Robert Allen, Ph.D., Chief Scientific Officer at Invivyd. "Pemivibart has now demonstrated antiviral activity in neutralization assays representing thirty-nine distinct SARS-CoV-2 variants across almost three years of rapid virus evolution. The ongoing pemivibart activity, with minimal quantitative change in neutralization activity, especially as compared to predecessor medicines such as Evusheld (tixagavimab/cilgavimab), is incredibly reassuring and validating of our fundamental R&D engine and potentiates our ability to successfully drug this target for long periods of time despite evolutionary pressure."
Clinical Implications and Regulatory Updates
Data demonstrating PEMGARDA's continued in vitro neutralizing activity against XEC have been submitted to the U.S. Food and Drug Administration (FDA). Invivyd anticipates a timely update to the PEMGARDA Fact Sheet for Healthcare Providers to reflect these new findings.
Amesh Adalja, MD, FIDSA, FACP, FACEP, Senior Scholar at the Johns Hopkins Center for Health Security, emphasized the importance of proactive viral monitoring: "Amidst the continual mutations that characterize SARS-CoV-2, proactively monitoring viral evolution as Invivyd is doing is a necessity in order to continuously test PEMGARDA against emerging variants of SARS-CoV-2. It is reassuring that PEMGARDA continues to show neutralizing activity against XEC, the current dominant circulating variant in the U.S. As we see COVID-19 numbers continue to rise through the respiratory season, PEMGARDA offers a valuable tool for certain moderately to severely immunocompromised patients who need options."
About PEMGARDA
PEMGARDA (pemivibart) is a half-life extended investigational monoclonal antibody (mAb) engineered from adintrevimab. It is authorized for emergency use by the U.S. FDA for pre-exposure prophylaxis (prevention) of COVID-19 in adults and adolescents (12 years of age and older weighing at least 40 kg) with moderate-to-severe immune compromise who are unlikely to mount an adequate immune response to COVID-19 vaccination. PEMGARDA targets the SARS-CoV-2 spike protein receptor binding domain (RBD), preventing virus attachment to the human ACE2 receptor on host cells.
