Developing Hapentized
Protein Vaccines

Haptenization is based on proven science, a well-understood mechanism of action, and extensive clinical data, with evidence that it can be used to treat multiple viral infections and any resectable solid tumor.

Inducing Targeted T-Cell
and Antibody Response

The BioVaxys vaccine platform is based on the concept of haptenization. This idea has a long history, beginning with the work of the immunologist and Nobel laureate Dr. Karl Landsteiner,

Simply put, the process of haptenization “teaches” a patient’s immune system to recognize and make target proteins more ‘visible’ as foreign, thereby stimulating a more intense immune response.   We now understand that T-cells (or T-lymphocytes, which are white blood cells that are crucial in tumor rejection) react against the haptenized material and that the T-cells also then react against the unmodified target protein. At BioVaxys, we believe that tumor and viral antigens, which are proteins, are similarly affected by haptenization which stimulates a T-cell mediated immune response.  

Besides having no observed toxicity in multiple clinical trials,  haptenization is based on proven science, a well-understood mechanism of action, and extensive clinical data, with evidence that it can be used to treat multiple viral infections and any resectable solid tumor.

Preclinical SARS-CoV-2
Vaccine Development

BVX-0320:  Our lead vaccine candidate in preclinical development for SARS-CoV-2.

BVX-0320 is a haptenized s-Spike protein of SARS-CoV-2 which is a critical protein on the surface of the virus that is required for the virus’ ability to bind to and enter human cells. The S protein is immunogenic and antibodies against it neutralized the virus. 

Studies have demonstrated that patients recovering from SARS-CoV-2 infection carried helper T-cells that recognized the SARS-CoV-2 S-spike protein, and virus-specific killer T-cells were detected in 70% of the test subjects. As haptenized proteins are known to induce potent T cell responses, we believe the BioVaxys approach could have an advantage over other developing SARS-Cov-2 vaccines. Furthermore, our clinical experience with haptenization and safety data from prior clinical development of haptenized vaccines may prove advantageous from a regulatory perspective and lead to an accelerated development process.


Bi-Haptenized Ovarian Cancer Tumor Cell Vaccine

BVX-0918A: Our lead haptenized tumor cell vaccine for ovarian cancer.  

BioVaxys’s cancer vaccines are created by extracting a patient’s own (e.g. ‘autologous’) cancer cells, chemically treating them with a hapten, and re-injecting them into the patient to induce an immune response to proteins which are otherwise not immunogenic.  Haptenization is a well-known and well-studied immunotherapeutic approach in cancer treatment, and has been clinically evaluated in both regional and disseminated metastatic tumors. A first generation single-hapten vaccine achieved positive immunological and clinical results in Phase I/II trials. At BioVaxys, we have enhanced this first generation approach to now utilize two haptens (“bi-haptenization”) which we believe will yield superior results. 

Single haptenization only modifies hydrophilic amino acids on antigenic proteins, but utilizing two different haptens modifies both both hydrophilic and hydrophobic amino acids on these target proteins, making the protein more foreign to the immune system with modification of additional amino acids.  A greater number of T cells is activated by the addition of another hapten (i.e., more modified amino acids) so the number of T cells potentially reactive to the unmodified protein increases.

Further, we plan to combine the use of our vaccine with anti-CTLA4 and anti-PDA checkpoint antibodies. The rationale is that these reagents on their own are powerful augmenters of cellular immune response;  We believe our vaccine changes the tumor environment to make them more susceptible to checkpoint mAbs (induction of TILs & activation markers), and we expect a synergistic response from the combination.