Invivyd Inc. (NASDAQ:IVVD) on Tuesday announced topline results from its Phase 3 LIBERTY study of its investigational COVID-19 monoclonal antibody candidate.

The study demonstrated that VYD2311 met primary and key secondary safety endpoints while enhancing antibody titers when combined with an mRNA vaccine.

Safety And Tolerability Outcomes

The double-blind study evaluated 210 healthy adults aged 18 to 49 across three treatment arms: VYD2311 alone, the Pfizer Inc. (NYSE:PFE)/BioNTech SE (NASDAQ:BNTX) Comirnaty mRNA vaccine alone, or a combination of both treatments.

Participants receiving VYD2311 alone reported a lower incidence of short-term treatment-emergent adverse events over six days at 56.5%, compared to 91.4% in the mRNA vaccine group.

Over the full 56 days, VYD2311 maintained favorable tolerability with a 60.9% adverse event rate versus 91.4% for the vaccine alone.

Short-term systemic adverse events occurred in 44.1% of participants receiving VYD2311 and 50.0% receiving the combination therapy, demonstrating statistically significant reductions compared to 68.1% for the mRNA vaccine alone.

Investigators observed no adverse events exceeding Grade 2 and recorded zero instances of hypersensitivity or anaphylaxis across all treatment groups.

Antibody Titers And Regulatory Strategy

The trial evaluated potential immunologic interference by measuring vaccine-induced neutralizing antiviral titers.

Combining VYD2311 with the mRNA vaccine increased neutralizing titers by approximately 2.5 times compared to the vaccine alone over 56 days.

When researchers removed VYD2311 from combination samples, neutralizing titers remained identical to the standalone vaccine arm, confirming an absence of immunologic interference.

Pharmacokinetic results met company expectations and target profiles under evaluation in the companion DECLARATION trial.

These comparative analyses suggest concomitant administration may improve vaccine safety while expanding neutralizing antiviral coverage.

Following a September Type C meeting and ongoing discussions with U.S. Food and Drug Administration leadership, the company intends to submit a Biologics License Application under the Accelerated Approval Program.

Invivyd will base the application on LIBERTY and DECLARATION data, while continuing post-approval clinical event collection in a randomized confirmatory cohort to evaluate efficacy.

IVVD Price Action: Invivyd shares were down 11.59% at $0.91 at the time of publication on Tuesday, according to Benzinga Pro data.

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