Altor BioScience - IMPACT Technology

Background

MHC molecules (or HLA molecules in humans), expressed on the surface of antigen presenting cells (APCs), play an essential role in displaying antigens from viruses and other pathogens to T-cells and subsequently stimulating the T cells to react against the pathogen. Usually, these responses are well-controlled such that T cells do not react against normal tissues. However in some individuals, inappropriate T cell responses against "self" antigens displayed in the MHC complex lead to tissue inflammation and damage and ultimately autoimmune disease, such as rheumatoid arthritis (RA), type I diabetes and multiple sclerosis (MS). Interactions between the autoimmune T cells via their TCRs and self antigen/MHC complexes on the tissues likely initiate and prolong these abnormal immune responses.

Altor's Approach

Altor is using its proprietary technologies to develop immunosuppressive agents for the control of T-cells involved in autoimmune diseases. IMPACT™ (Inhibitor of MHC-Peptide Activation of T-cells) therapeutics are designed to reduce specific autoimmune T-cell activity resulting from the interactions between TCRs and self antigen/MHC complexes, while leaving the rest of the immune system unaffected. A major advantage of this approach is that it selectively corrects the aberrant immune responses by targeting MHC molecules genetically linked to disease initiation and progression.

Employing its patented single-chain MHC format, Altor has generated soluble antigen-MHC proteins (IMPACT™ Fusions) capable of altering T cell signaling to switch-off autoreactive responses. In addition, Altor has developed a number of proprietary high-throughput STAR-IMPACT™ screening assays to identify small molecule compounds that affect MHC-peptide:TCR interactions. Particular focus is on MHC antagonists blocking TCR interactions with disease-associated HLA molecules, such HLA-DR2 and HLA-DR4. Altor has established proof-of-concept that non-toxic chemical compounds can be isolated that specifically inhibit TCR:HLA-peptide interactions as well as HLA-restricted T-cell responses in animal models. Altor believes that orally active pharmaceutical compounds discovered through this screening technology would have broad application for treating a number of autoimmune diseases. Altor is seeking partnership opportunities for development of these technologies and product candidates.