News Release

Sigma-Tau Pharmaceuticals, Inc. Receives Orphan Drug Designation for EZN-2279 for Treatment of Adenosine deaminase–deficient Severe Combined Immunodeficiency Disease



Gaithersburg, MD, March 30, 2015 — Sigma-Tau Pharmaceuticals Inc. announced today that the U.S. Food and Drug Administration (FDA) has granted an orphan drug designation for the Company’s investigational compound EZN-2279, a PEGylated recombinant version of Sigma Tau’s presently commercially marketed drug, Adagen®(pegademase bovine) for treatment of patients with adenosine deaminase (ADA) deficiency in patients with severe combined immunodeficiency. ADA-SCID is caused by mutations (defects) in the ADA gene, which are responsible for expressing the enzyme adenosine deaminase. EZN-2279, like Adagen®, is an enzyme replacement therapy, presently in Phase 3 clinical trials being conducted at multiple sites in the United States.

“We are pleased to have received an orphan drug designation for EZN-2279 as it represents an important regulatory milestone to advance EZN-2279 as a potential treatment for ADA-SCID,” said Dave Lemus, Chief Executive Officer of Sigma-Tau Pharmaceuticals, Inc. "We are encouraged by the progress of the program to date, and this designation underscores our commitment not only to our existing patients receiving Adagen®, but also to the further development of treatments for ADA-SCID patients.”

An Orphan drug designation is granted by the FDA Office of Orphan Products Development to novel drugs that treat a rare disease or condition affecting fewer than 200,000 patients in the U.S. The designation provides the beneficiary company with a seven-year period of U.S. marketing exclusivity, as well as potential tax credits for clinical research costs, federal grants, and a waiver of Prescription Drug User Fee Act (PDUFA) filing fees.

About ADA-SCID

Severe combined immunodeficiency due to adenosine deaminase deficiency is a form of SCID characterized by very low levels of white blood cells and immunoglobulin levels, resulting in severe and recurring infections. The largest number of patients with ADA deficiency (about 85% to 95%) present with ADA-SCID, which is the most severe form of the immunodeficiency, and its annual incidence is estimated to be between 1 in 200,000 and 1 in 1,000,000 live births. ADA-SCID usually presents in infancy and left untreated usually results in patient death by two years of age.

About Adagen®

Adagen®, approved by the FDA in 1990, represents the first successful application of enzyme replacement therapy for an inherited disease. In the absence of the enzyme ADA, the purine metabolite 2’ deoxyadenosine is toxic to immature lymphocytes. Adagen® injection is indicated for enzyme replacement therapy for adenosine deaminase (ADA) deficiency in patients with severe combined immunodeficiency disease (SCID) who are not suitable candidates for – or who have failed – bone marrow transplantation. There are presently less than 100 diagnosed patients in the United States receiving treatment for ADA-SCID with Adagen®.

Important Safety Information

  • ADAGEN® (pegademase bovine) Injection is recommended for use in infants from birth or in children of any age at the time of diagnosis. ADAGEN® (pegademase bovine) Injection is not intended as a replacement for HLA identical bone marrow transplant therapy. ADAGEN® (pegademase bovine) Injection is also not intended to replace continued close medical supervision and the initiation of appropriate diagnostic tests and therapy (e.g., antibiotics, nutrition, oxygen, gammaglobulin) as indicated for intercurrent illnesses.
  • There is no evidence to support the safety and efficacy of ADAGEN® as preparatory or support therapy for bone marrow transplantation. Since ADAGEN® is administered by intramuscular injection, it should be used with caution in patients with thrombocytopenia and should not be used if thrombocytopenia is severe.
  • The optimal dosage and schedule of administration should be established for each patient. Plasma ADA activity and red cell dATP should be determined prior to treatment. The treatment of SCID associated with ADA deficiency with ADAGEN® should be monitored by measuring plasma ADA activity and red blood cell dATP levels.
  • The following adverse reactions were reported during clinical trials: headache in one patient and pain at the injection site in two patients.

Please see full Prescribing Information for contraindications, precautions and adverse reactions.

About Sigma-Tau Pharmaceuticals, Inc

Sigma-Tau Pharmaceuticals, Inc. is a U.S. based, wholly owned subsidiary of the sigma-tau Group, and is dedicated to the global development and commercialization of medicines for patients with rare diseases. Sigma-Tau Pharmaceuticals, Inc. is based in Gaithersburg, Maryland, and the company’s marketed products are focused on cancer, kidney disease, gastrointestinal and genetic related disorders. The company also has clinical development programs focused on hematological cancer, malaria, and other areas of unmet medical need. For more information about Sigma-Tau Pharmaceuticals, Inc., visit www.sigmatau.com.

Contact at Sigma-Tau:
Dave Lemus (CEO)
Sigma-Tau
301-670-1522

Contact for Sigma-Tau (Media):
Eric Goldman
Rx Communications Group, LLC
917-322-2563
egoldman@RxIR.com