L-histidine is being developed as a prescription drug and as a dietary supplement for 1) chronic inflammatory gastrointestinal diseases; 2) conjunctivitis and seasonal allergic rhinitis; 3) infectious and non-infectious diarrheas; and 4) as an antioxidant

This is a unique opportunity to acquire a proprietary application of the cytoprotective aspects of L-histidine in the medical foods, dietary supplement, and pharmaceutical markets. Cytos has two products under development for which L histidine is the active ingredient - Zolomid® oral rehydration solution and Oxavert® antioxidant dietary supplement.

Though there are certain dietary supplements containing histidine on the market, there is not a single approved histidine drug product in the United States, nor are there currently marketed supplements that combine L-histidine with a cytoprotective agent or with other antioxidant compounds. Such factors will allow Cytos to differentiate its histidine products from competitors and obtain stronger IP protection for its products.

Cytos Pharmaceuticals is actively leveraging the expertise of Cato Research Ltd. and Cato BioVentures in developing histidine as a drug, dietary supplement, and medical food, as well as actively seeking partners to penetrate both the pharmaceutical and supplement markets. A combination of experienced management, close CRO assistance, strong patent protection, and a safe, well-studied and proven product put Cytos in a position to develop strong, competitive products in three arenas concurrently.

Preclinical

Cytos currently holds 8 patents for L-histidine in multiple indications:

• U.S. Patent No. 5,280,038 ("Histidine as a Protective Agent in Cardiac Surgery and Myocardial Ischemic Syndrome") was filed on 13 March 1992 and issued on 18 January 1994. Cytos has licensed the patent from Virginia Commonwealth University.

• U.S. Patent No. 5,352,691 ("Effective Treatment Modality for Adult Respiratory Distress Syndrome Using L-Histidine") was filed on 16 February 1993 and issued on 04 October 1994.

• U.S. Patent No. 5,658,937 ("Effective Treatment Modality for Infectious Diseases, Pulmonary Conditions and Sequeale Thereof") was filed on 30 September 1994 and issued on 19 August 1997.

• U.S. Patent No. 5,710,172 ("Histidine as a Protective Agent in Cardiac Surgery and Myocardial Ischemic Syndromes") was filed on 07 June 1995 and issued on 20 January 1998. Cytos has licensed the patent from Virginia Commonwealth University.

• U.S. Patent No. 5,741,807 ("Histidine Compositions and Methods for Treating or Preventing Infectious and Non-Infectious Diarrheas") was filed on 27 September 1996 and issued on 21 April 1998.

• U.S. Patent No. 5,811,446 ("Prophylactic and Therapeutic Methods for Ocular Degenerative Diseases and Inflammations and Histidine Compositions Therefor") was filed on 18 April 1997 and issued on 22 September 1998.

• U.S. Patent No. 5,854,271 ("Effective Method for the Amelioration and Prevention of Tissue and Cellular Damage") was filed on 14 April 1997 and issued on 29 December 1998.

• U.S. Patent No. 6,329,414 ("Histidine Containing Nutriceutical") was filed on 10 September 1999 and issued on 11 December 2001.

Cytos is seeking a developmental partner for Oxavert® and other forms of L-histidine for clinical use in the United States.