Telik, Inc, announced that its product candidate, ezatiostat hydrochloride (Telintra), has been granted orphan drug designation by the FDA for the treatment of myelodysplastic syndromes (MDS).
Ezatiostat is an investigational agent in development for the treatment of MDS and idiopathic chronic neutropenia. The drug is a novel inhibitor of the enzyme glutathione S-transferase P1-1, leading to activation of Jun kinase, a key regulator of cellular growth and differentiation of blood precursor cells.
Ezatiostat has been shown to cause clinically significant and sustained reduction in red blood cell transfusions, transfusion independence, and multilineage responses in patients with multidysplastic syndromes. The results of four clinical trials of ezatiostat in MDS have been reported in peer-reviewed scientific journals.
Orphan designation grants potential U.S. market exclusivity to a drug for the treatment of a specified condition for a period of 7 years following FDA marketing approval. Additional potential benefits of orphan designation include development grants, tax credits related to clinical trial expenses, protocol development assistance and exemption from FDA user fees. The U.S. Orphan Drug Act aims to encourage the development of drugs for the diagnosis, prevention and treatment of medical conditions affecting fewer than 200,000 people in the United States. ■