Technology

A unique antibody platform

Our platform technology uses camelid antibody fragments (VHH) as building blocks to create novel antibodies for the prevention and treatment of infectious diseases. The platform enables a rapid and robust response to existing and future public health threats:

Multi-specific constructs target multiple epitopes at the same time, making the constructs robust against fast-moving mutations.

VHH can bind “hidden” epitopes that are typically well conserved, resulting in broad specificity. 

The resulting therapeutics are stable and cost-effective and easy to produce, facilitating global access.

What are VHH?

Conventional antibodies are comprised of 2 heavy chains and 2 light chains of amino acids.

Camelids also produce a different kind of antibodies, consisting of only 2 heavy chains.

Their specificity is determined by a single variable domain (VHH), which retains its antigen-binding potential as a separate fragment.

MODULAR MULTI-SPECIFIC MEDICINES

Thanks to their small size, VHH can be used as building blocks that are linked using a human Fc region – corresponding to the “tail” of a conventional antibody – as a backbone. 

These constructs can combine multiple VHH (with the same and/or a different specificity) in different ways.

Monospecific bivalent VHH-Fc
Bispecific monovalent knob-into-hole VHHx-VHHy-Fc
Bispecific bivalent tandem VHHx-VHHy-Fc
Trispecific bivalent tandem VHHx-VHHy-VHHz-Fc
Bispecific bivalent VHHx-Fc-VHHy

UNIQUE BENEFITS

BROAD
SPECIFICITY

Thanks to their small size and unique structural properties, VHH can bind epitopes that are inaccessible to conventional antibodies. 

Such “hidden epitopes” are often well-conserved between variants and subtypes, giving the VHHs that bind them a broad specificity.

REDUCED RISK OF IMMUNE ESCAPE

By targeting multiple epitopes simultaneously, a pathogen must evolve each of them to acquire resistance. 

Combining specificities in a single molecule is superior to using antibody cocktails, as the manufacturing cost is lower and obtaining regulatory approval is less complex.

IMPROVED
DOSING

VHH are quickly cleared by the kidneys. Linking them to an Fc region increases their serum half-life, meaning lower doses or less frequent administration are needed.

MULTIPLE MECHANISMS OF ACTION

In addition to the ability of the VHH to prevent infection, the Fc region induces an immune response against the pathogen. The strength of this response can be fine-tuned by adapting the sequence of the Fc region.

BETTER TISSUE PENETRATION

Their favorable solubility, stability, and biodistribution profiles enable faster and better tissue penetration than conventional antibodies.

EASY AND COST-EFFECTIVE PRODUCTION

They can be synthesized using microbial systems such as Pichia, generating high yields of homogeneous products.

HIGHER
POTENCY

The presence of two identical VHH in bivalent constructs improves binding.

PUBLICATIONS

Ultrapotent SARS coronavirus-neutralizing single-domain antibodies that bind a conserved membrane proximal epitope of the spike

Currently circulating SARS-CoV-2 variants have gained complete or significant resistance to all SARSCoV-2-neutralizing antibodies that have been used in the clinic. Such antibodies can prevent ...

Structural Basis for Potent Neutralization of Betacoronaviruses by Single-Domain Camelid Antibodies

Using llamas immunized with prefusionstabilized betacoronavirus spike proteins, Wrapp et al. identify neutralizing cross-reactive single-domain camelid antibodies, which may serve not only as useful reagents ...