1 December 2020 - - The US Food and Drug Administration has extended the Prescription Drug User Fee Act (PDUFA) date for review of a Biologics License Application seeking accelerated approval of pegunigalsidase alfa (PRX–102) for the proposed treatment of adult patients with Fabry disease, Israel-based biopharmaceutical company Protalix BioTherapeutics, Inc. (NYSE American: PLX) (TASE: PLX) and Italy-based healthcare Group Chiesi Farmaceutici S.p.A.'s Chiesi Global Rare Diseases unit said.

The FDA extended the PDUFA action date by three months to April 27, 2021, from January 27, 2021.

As previously announced, the FDA accepted the BLA, granted Priority Review designation under FDA's Accelerated Approval pathway, and indicated that it is not currently planning to hold an advisory committee meeting to discuss the application.

Priority Review is granted to therapies that the FDA determines have the potential to provide significant improvements in the treatment, diagnosis or prevention of serious conditions.

The BLA submission includes a comprehensive set of preclinical, clinical, and manufacturing data compiled from the company's completed Phase I/II clinical trial of pegunigalsidase alfa, including the related extension study succeeding the Phase I/II clinical trial, interim clinical data from the Phase III BRIDGE switch-over study and safety data from the company's on-going clinical studies of PRX–102 in patients receiving 1 mg/kg every other week.

Pegunigalsidase alfa (PRX–102) is an investigational, plant cell culture-expressed, and chemically modified stabilized version of the recombinant α-Galactosidase-A enzyme.

Protein sub-units are covalently bound via chemical cross-linking using short PEG moieties, resulting in a molecule with unique pharmacokinetic parameters.

In clinical studies, PRX–102 has been observed to have a circulatory half-life of approximately 80 hours. The company designed PRX–102 to potentially address the continued unmet clinical need in Fabry patients.

Protalix is a biopharmaceutical company focused on the development and commercialization of recombinant therapeutic proteins expressed through its proprietary plant cell-based expression system, ProCellEx. Protalix was the first company to gain FDA approval of a protein produced through plant cell-based in suspension expression system. 

Protalix's unique expression system represents a new method for developing recombinant proteins in an industrial-scale manner.

Protalix's first product manufactured by ProCellEx, taliglucerase alfa, was approved for marketing by the FDA in May 2012 and, subsequently, by the regulatory authorities of other countries. 

Protalix has licensed to Pfizer Inc. (NYSE: PFE) the worldwide development and commercialization rights for taliglucerase alfa, excluding Brazil, where Protalix retains full rights.

Protalix has partnered with Chiesi Global Rare Diseases, both in the United States and outside the United States, for the development and commercialization of pegunigalsidase alfa.