Additional data from Phase III clinical trial of taliglucerase alfa in patients with Gaucher disease presented

Protalix BioTherapeutics, Inc. (NYSE-Amex: PLX), announced today that additional data from the Company's pivotal Phase III clinical trial of taliglucerase alfa in patients with Gaucher disease was presented at the Annual Meeting of the Lysosomal Disease Network: WORLD Symposium 2010 in Miami, Florida, during an oral session titled, "Novel Enzyme Replacement Therapy for Gaucher Disease: Phase III Pivotal Clinical Trial with Plant Cell Expressed Recombinant Glucocerebrosidase (prGCD) - taliglucerase alfa." The oral presentation was made by Hanna Rosenbaum M.D., Director of Hematology Day Care Unit, RAMBAM Medical Center, Haifa, Israel, and study investigator.

"I believe the data from the Phase III trial demonstrates that taliglucerase alfa is well tolerated and clinically effective in treating Gaucher disease," said Dr. Hanna Rosenbaum.

The pivotal Phase III clinical trial was a multi-center, world-wide, randomized, double-blind, parallel group, dose-ranging study to assess the safety and efficacy of taliglucerase alfa in 31 treatment-naive patients suffering from Gaucher disease. In the trial, patients were selected randomly for one of two dosing arms (60 U/kg or 30 U/kg) and received intravenous infusions of taliglucerase alfa once every two weeks for a nine month period.  The primary endpoint of the study was a 20% mean reduction from baseline in spleen volume after nine months, as measured by MRI. Major secondary endpoints were an increase in hemoglobin, decrease in liver volume and increase in platelet count.  The trial enrolled patients at 11 centers throughout Europe, Israel, North America, South America and South Africa.

Taliglucerase alfa significantly reduced mean spleen volume after nine months compared with baseline in both treatment groups.  The 60 U/kg group demonstrated a statistically significant mean reduction in spleen volume of 38.0% (p<0.0001) and the 30 U/kg group demonstrated a significant mean reduction in spleen volume of 26.9% (p<0.0001).   In addition, the primary endpoint was achieved in both treatment groups after only 6 months of therapy.

Statistically significant improvements were also observed for the secondary endpoints after nine months when compared to baseline for the 60 U/kg dose. Patients demonstrated a mean increase in hemoglobin of 2.2 g/dL or 22.2% (p<0.0001), a mean decrease in liver volume of 11.1% (p<0.0001) and a mean elevation in platelet count of 41,494 ml or 72.1%>

Thirty patients in the trial had Chitotriosidase measurements, a biomarker for clinical symptoms of Gaucher disease.  In these patients, Chitotriosidase decreased from baseline in both the 30U/kg and 60U/kg groups by 47.3% and 58.4% respectively.

The safety analysis for both treatment groups showed that taliglucerase alfa was well tolerated and no serious or severe adverse events were reported.  Two patients in the trial developed antibodies to taliglucerase alfa and no patients developed neutralizing antibodies.  In addition, two patients experienced hypersensitivity reactions to taliglucerase alfa.  No anti-taliglucerase antibodies were detected in these patients and both reactions were treated in the physicians' clinic and reversed.

Most adverse events were considered unrelated to taliglucerase alfa. The most frequent mild to moderate adverse event was headache.  Other mild to moderate adverse events included dizziness, muscle spasm, chest discomfort, nausea, skin irritation and arthalgia.  

"The Phase III results reported today not only support the use of taliglucerase alfa for the treatment of Gaucher disease, but also support the Company's plant cell based platform technology," said Dr. David Aviezer, President and CEO of Protalix.  "Patients who successfully completed this pivotal study have continued to receive taliglucerase alfa as part of our ongoing extension trial, some for over two and a half years."  

The Company is currently conducting a world-wide switch over study investigating the efficacy and safety of switching to taliglucerase alfa from the currently approved enzyme replacement therapy. In addition, taliglucerase alfa is being provided to patients in the United States under an Expanded Access protocol and to patients in the European Union, Israel and other countries under Named Patient provisions.