Affimed's program for auto-immune disease is intended to target moderate to severe psoriasis, but would also be appropriate for the treatment of other auto-immune diseases, such as inflammatory bowel disease and type I diabetes. Affimed has developed AFM15 in both a Diabody and a TandAb format that comprises only the variable domains of an anti-CD3 antibody which were modified by substituting two critical amino acids to improve the stability and folding properties. CD3 is an especially well characterized receptor for the binding and activation of T-cells. By blocking CD3, AFM15 limits the destructive cytokine release characteristic of auto-immune disease. CD3 is a clinically validated target for auto-immune disease.
Psoriasis
Psoriasis is an auto-immune disease affecting the skin and joints characterized by the appearance of red scaly patches on the skin. These scaly patches, psoriatic plaques or lesions, are areas of excessive skin production and inflammation caused by immune activation. Like all auto-immune diseases, psoriasis is chronic and recurring and can be aggravated by stress. In some cases the inflammation can also affect the joints, psoriatic arthritis, as well as finger and toenails. The cause of the disease appears to be the activation of T cells that migrate to the skin and trigger the release of cytokines. It is not known what causes this T cell activation but treatment with immunosuppressants that block T cell activation has been shown to clear psoriasis plaques.
Preclinical studies
In vitro tests demonstrated improved immunosuppressive activity and a drastic reduction in the amount of released cytokines. When compared with monoclonal antibodies, AFM15 triggered fewer side effects and demonstrated reduced immunogenicity due to the absence of constant domains. Furthermore, because of its small size, AFM15 in both formats can be produced more cost-effectively in bacteria. Due to the significant reduction of released cytokines this immunosuppressive product can potentially be used for treating a wider range of indications as described above.
Affimed intends to identify the most appropriate antibody format for the target indication moderate to severe psoriasis, and progress with in vivo and in vitro preclinical studies.
Licensing
Affimed welcomes interest from potential licensing partners for the co-development of AFM15.