Protalix: New data from taliglucerase alfa, oral GCD trials to be presented at Lysosomal Disease Network Symposium

Protalix BioTherapeutics, Inc. (NYSE-AMEX: PLX, TASE: PLX), announced today that new clinical data from the switchover trial of taliglucerase alfa in Gaucher disease patients and preclinical data on oral enzyme glucocerebrosidase (oral GCD) will be presented today at the 7th Annual Meeting of the Lysosomal Disease Network: WORLD Symposium 2011 in Las Vegas, Nevada.  Both drug candidates are unique in that they are produced through the Company's proprietary plant-cell protein expression system.

Switchover Trial of taliglucerase alfa

Gregory Pastores, M.D., Associate Professor of Neurology and Pediatrics and Director of the Neurogenetics Laboratory at New York University School of Medicine and a study investigator, will present new data from the Company's switchover trial during an oral session titled: "Plant Cell Expressed Recombinant Glucocerebrosidase taliglucerase alfa as Therapy for Gaucher Disease in Patients Previously Treated with Imiglucerase."

"Interim results from the switchover trial support the safety and maintenance of efficacy of taliglucerase alfa in patients with Gaucher disease who were previously on imiglucerase," said Dr. Gregory Pastores.

The switchover trial is a phase III multicenter, open-label clinical trial designed to assess the safety and efficacy of taliglucerase alfa in Gaucher disease patients who are currently being treated with imiglucerase (Cerezyme®) enzyme replacement therapy.  Patients eligible for the switchover trial are evaluated for 12 weeks to establish the stability of their disease.  Patients with confirmed stable disease are switched from imiglucerase (doses ranging from 10-60 U/kg every other week) to an equivalent dose of taliglucerase alfa using the same number of units for a nine-month period.  Adult enrollment in the study has been completed>North America, Europe, Israel and Australia.

Dr. Pastores will present clinical trial data from an interim report completed in August 2010 which includes efficacy data from 15 patients and safety data from 25 patients.  The data indicate that patients can safely be switched to taliglucerase alfa from imiglucerase.

The Company and Pfizer Inc. have filed a new drug application (NDA) or a marketing authorization application (MAA), as applicable, for taliglucerase alfa in the United States, European Union, Brazil and Israel.  The Company received a Prescription Drug User Fee Act (PDUFA) date of February 25, 2011 from the U.S. Food and Drug Administration for the taliglucerase alfa NDA.

Oral Enzyme glucocerebrosidase

Yoseph Shaaltiel, Ph.D., the Company's Executive Vice President, Research and Development, will present preclinical data on the Company's oral enzyme glucocerebrosidase (oral GCD) during an oral session titled: "Oral Delivery of Recombinant Glucocerebrosidase Enzyme Naturally Encapsulated in Carrot Cells."  Oral GCD is a plant cell expressed form of GCD that is naturally encapsulated within carrot cells genetically engineered to express the GCD enzyme.

Preclinical studies of oral GCD demonstrate the stability of the enzyme in the cell and the capacity of the cell's cellulose wall to protect the enzyme against degradation in the digestive tract in an in-vitro model of the stomach and intestines.  Additionally, rats fed lyophilized carrot cells expressing GCD have accumulated the active enzyme in the target organs, the spleen and liver.

Oral GCD is being developed for the treatment of Gaucher disease.  The Company intends to initiate phase I clinical trials in carriers of Gaucher disease who show reduced enzymatic activity at baseline.