The Next Generation of Virus Like Particles (VLP)

Lead Product

CBI’s lead product is a new kind of vaccine cellular mechanism. Its market entry will help recombinant antigen vaccines deliver on the promise of increased safety by enhancing their immunogenicity while reducing required doses.

CBI-3A increases and improves vaccine induced responses by all three elements of the adaptive immune system and promotes antigen specific mucosal IgA, IgG and T-cell responses, even when vaccination is administered by a non-mucosal route.

The CBI Virus Like Particle is a heavily deleted alphavirus RNA genome packaged in alphavirus proteins.

Reference for this figure is Proc. Natl. Acad. Sci. USA, Vol. 90, pp. 9095-9099, October 1993

The need for safe and effective vaccines has never been greater…

Our proprietary CBI-3A has been studied extensively in pre-clinical studies (with model antigens, peptides and licensed and experimental vaccines) and has shown the following in multiple species, including non-human primates:

  • Excellent VLP-induced elevation of immune responses.
  • Significantly increased protection against challenge with the target pathogen.
  • No significant safety signals attributable to the adjuvant in any of the animals studied.


Benefits of CBI-3A

Broad Protection

Clarus’ VLP elicits immunity from all three elements of the adaptive immune system.

Vaccine effectiveness increases dramatically when all elements are activated (including mucosal immune responses, which initiate protection where many pathogens enter the body).

Dose Sparing

Clarus’ adjuvant has been shown to increase vaccine protection by >100x while also reducing the required dose.

Lowering the effective dose ten to twenty fold alleviates supply constraints and reduces potential safety risks.

Increases AB Response

Increases T-Cell Response

Elicits Mucosal Immunity

Increases Protection 

Its novel properties place CBI-3A in a unique position within the vaccine VLP market

CBI-3A is the only adjuvant under development that functions by stimulating the same system for inducing an innate immune response as a naturally occurring viral infection.


Induces antibodies and T cells, both typically important for strong protection and recovery from disease


Induces mucosal immunity in animal models

Frequently Asked Questions


How do vaccines work?

Vaccines train our immune systems to recognize and respond to disease causing germs (pathogens) so that, in the future, should we be exposed to these pathogens, the body knows how to fight them.


Why do vaccines need helper VLPs?

Most vaccines being developed today contain small parts of pathogens rather than the entire virus or bacteria. This makes them safer to manufacture and safer in patients. However, it also makes them less effective at eliciting an immune response from the body. As a result, adjuvants are used in conjunction with vaccines to enhance the strength and quality of the immune response to such vaccines.


What is a vaccine adjuvant? Do VLPs technically match adjuvants?

In immunology, an adjuvant is a substance that increases and/or modulates the immune system’s response to a vaccine (the word adjuvant is derived from the Latin, adiuvare, meaning to help or aid). In other words, they help vaccines work better. Generally minerals like aluminum are deemed simple helpers that stimulate the immune system but Clarus’ VLP is a cellular mechanism that effectively turns on the immune system response.


How does CBI-3A work? What Makes it different?

An optimal adaptive immune response to a pathogen typically requires two elements: 1) a protein antigen, derived from the target pathogen to which a desired immune response will be directed, and 2) a signal which tells the body that it should respond strongly to this antigen.  This second signal is a non-specific “innate immune response” during which key chemical mediators of the immune system are released.  During a naturally-occurring infection, when the antigen is part of the infecting pathogen, the innate immune response is induced by the replicating pathogen itself or byproducts of the pathogen’s replication.  During vaccination, the innate response can be activated by a VLP.

One of the strongest inducers of an innate response is the replication of viral RNA inside the cell.

The Clarus Biologics VLP, CBI-3A, is mixed with a vaccine antigen and inoculated into the body, where each vaccine component (antigen and VLP) travel independently to the lymph node draining the site of inoculation.  There, a small piece of a viral RNA, contained within CBI-3A, enters specialized lymphoid cells, and begins to replicate as if it were a real virus RNA.  This process is detected by the cell, an innate response is triggered, and the adaptive (specific) immune response is focused on the inoculated vaccine antigen also present in the lymph node.  The adaptive immune response to the vaccine antigen is greatly improved, both quantitatively and qualitatively, in the presence of CBI-3A compared with vaccine which contains the protein antigen alone.

At Clarus Biologics our mission is to increase the availability of safe and effective prophylactic and therapeutic technologies.

Contact Now


5151 McCrimmon Parkway

Morrisville, NC, USA

Copyright © 2024 - Clarus Biologics Inc.