Celtaxsys Lead Candidate Granted Orphan Designation in Cystic Fibrosis by FDA

ATLANTA, Feb. 3, 2015 /PRNewswire/ — Celtaxsys, Inc., a clinical stage biotechnology company focused on
advancing break through medicines to treat inflammatory mediated diseases, today announced that the U.S. Food
and Drug Administration (FDA) has granted orphan drug designation (ODD) to its once daily, oral leukotriene A4
hydrolase inhibitor (CTX-4430) for the treatment of cystic fibrosis (CF). The U.S. orphan designation complements
the orphan designation for use of CTX-4430 in the treatment of CF in the European Union granted late last year by
the European Medicines Agency.
“We are pleased to have received orphan drug designation for CTX-4430 to treat the inflammatory component of
cystic fibrosis, a disease that still results in unacceptable levels of morbidity and pre-mature mortality,” said Greg
Duncan, President and Chief Executive Officer. “By down regulating over activated neutrophils and reducing
neutrophil elastase in the lungs, we hope to preserve small airway cell structure, reduce lung clogging and to
enhance CF patient lung function over time. Celtaxsys has now been granted orphan designation for CTX-4430 in
both the US and the EU, geographies in which 90% of CF patients reside. We are currently scaling capital to
progress CTX-4430 into a phase 2 trial later this year in CF for treatment of patients 18 years of age and older.”
Orphan drug designation is granted by the FDA Office of Orphan Products Development to novel drugs or biologics
that treat rare diseases or conditions affecting fewer than 200,000 patients in the US. The designation provides the
drug developer with a seven-year period of U.S. marketing exclusivity upon approval, as well as certain financial
incentives that can help support its future development.
About Cystic Fibrosis: Cystic fibrosis (CF) is a chronic disease that affects the lung and digestive system and
impacts 70,000 patients worldwide. CF is caused by a gene deficiency leading to abnormal protein functioning,
the result of which causes the body to produce excessive levels of unusually thick mucous in the lungs and pancreas.
This excessive sticky mucous clogs the lungs, leading to life threatening infections and hospitalization, as well
as altering pancreatic ability to break down and absorb food.
Respiratory distress in CF, defined as acute difficulty in breathing, infection and/or hospitalization, is most commonly
related to persistent lung infection and lung tissue damage. This distress is the result of an overwhelming and
dysfunctional response by neutrophils. Treatment of this lung inflammation is, therefore, a key to CF patient
well-being and longevity.
About Celtaxsys: Celtaxsys is a privately-held drug discovery and development company focused on advancing
medicine to treat patients suffering from serious inflammatory mediated diseases. The company is building a
sustainable pipeline of first-in-class immuno-modulators, the most advanced of which is CTX-4430.
Our leading drug candidate, orally administered CTX-4430, completed a 96-subject Phase 1 clinical trial in August
2013 and a Phase 1B trial in adult cystic fibrosis patients in October 2014. Oral CTX-4430 will enter Phase 2 trials
for adult cystic fibrosis and moderately-severe acne in 2015.
Celtaxsys is also developing topical applications of CTX-4430, as well as Second-Generation LTA4H inhibitors
(LTA4H-I). These are being optimized and tested in preclinical studies. The additional LTA4H-I include new intellectual
property and exhibit differentiated properties that enable optimization for alternate routes of administration.
Importantly, LTB4 inhibition has been shown to be effective in treating additional pulmonary diseases such as
Pulmonary Arterial Hypertension, Idiopathic Pulmonary Fibrosis and Non-CF Bronchiectasis, suggesting that the
platform may have substantial utility in treating a broad array of currently underserved patient populations.