Protalix Reports Positive Interim Data in Late-Stage Fabry Study

Protalix BioTherapeutics reported positive 12-month data from in a late-stage study of its plant cell culture expressed enzyme to treat Fabry disease, a rare lysosomal storage disorder.

Fabry disease is an X-linked inherited disease that results from deficient activity of the enzyme alpha galactosidase A resulting in progressive accumulation of abnormal deposits of a fatty substance called globotriaosylceramide (Gb3) in blood vessel walls throughout a person’s body. Fabry patients inherit a deficiency of the enzyme alpha-galactosidase-A, which is normally responsible for the breakdown of Gb3. The abnormal storage of Gb3 increases with time and, accordingly, Gb3 accumulates, primarily in the blood and in the blood vessel walls. The ultimate consequences of Gb3 deposition range from episodes of pain and impaired peripheral sensation to end-organ failure – particularly of the kidneys, but also of the heart and the cerebrovascular system.

Pegunigalsidase alfa is an experimental, plant cell culture expressed enzyme, and a chemically modified stabilized version of the recombinant alpha-galactosidase-A protein. In clinical studies, pegunigalsidase alfa has been observed to have a favorable circulatory half-life of approximately 80 hours. In addition, in a Fabry mouse model, pegunigalsidase alfa was observed to have favorable levels of enzyme activity in target organs affected by Fabry disease.

Protalix released 12-month data on the first 16 of 22 patients in the BRIDGE study. The BRIDGE study is an open label switch-over study evaluating the safety and efficacy of pegunigalsidase alfa (PRX-102), 1 mg/kg infused every two weeks, in up to 22 Fabry patients currently treated with agalsidase alfa (Replagal) for at least two years and on a stable dose for at least six months. The company said the data showed a mean improvement in kidney function, in both male and female patients, when switched from agalsidase alfa to pegunigalsidase alfa.

“These new results, after 12 months of treatment, further suggest the strong potential benefit of pegunigalsidase alfa on renal function for Fabry patients,” said Raul Chertkoff, Protalix’s vice president of medical affairs.

Pegunigalsidase alfa was found to be well tolerated in the study, with all adverse events being transient in nature without sequelae. Most of the patients who were eligible for home care therapy per country regulation were treated under a home care arrangement in which certain of the scheduled infusions were performed at the patients’ homes.

Photo: Raul Chertkoff, Protalix’s vice president of medical affairs.

Author: Rare Daily Staff