PRX-115 is a PEGylated recombinant uricase produced from the proprietary ProCellEx® platform as a potential treatment of severe gout

CARMIEL, Israel I March 21, 2023 I Protalix BioTherapeutics, Inc. (NYSE American: PLX) (TASE: PLX), a biopharmaceutical company focused on the development, production and commercialization of recombinant therapeutic proteins produced by its proprietary ProCellEx® plant cell–based protein expression system, today announced that the first patient has been dosed in the Company’s phase I First in Human (FIH) clinical trial of PRX-115, the Company’s recombinant PEGylated uricase product candidate under development as a potential treatment of severe gout.

The phase I FIH trial is a double-blind, placebo-controlled trial designed to evaluate the safety, pharmacokinetics, pharmacodynamics (reduction of uric acid) and immunogenicity of PRX-115 in patients with elevated uric acid levels (>6.0 mg/dL). The trial is a single ascending dose (SAD) study with up to seven cohorts, and patients are to be randomized 3:1 to receive a single intravenous (IV) dose of PRX-115 or a placebo. The study is being conducted at New Zealand Clinical Research (NZCR) under the New Zealand Medicines and Medical Devices Safety Authority (MedSafe) and the Health and Disability Ethics Committee (HDEC) guidelines, and is expected to enroll approximately 56 patients with no previous exposure to PEGylated uricase.

“We are pleased to initiate this first in human trial of PRX-115,” said Dror Bashan, Protalix’s President and Chief Executive Officer. “This milestone highlights our commitment to building and strengthening our pipeline. Given our corporate mission to deliver new medicines to patients with high, unmet needs, we look forward to continued enrollment and dosing of patients in this trial.”

About Protalix BioTherapeutics, Inc.

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. It is the first company to gain U.S. Food and Drug Administration (FDA) approval of a protein produced through plant cell-based in suspension expression system. This unique expression system represents a new method for developing recombinant proteins in an industrial-scale manner. Protalix has licensed to Pfizer Inc. the worldwide development and commercialization rights to taliglucerase alfa, Protalix’s first product manufactured through ProCellEx, excluding in Brazil, where Protalix retains full rights.

Protalix’s development pipeline consists of proprietary versions of recombinant therapeutic proteins that target established pharmaceutical markets, including the following product candidates: pegunigalsidase alfa, a modified stabilized version of the recombinant human α–Galactosidase–A protein for the treatment of Fabry disease; PRX–115, a plant cell-expressed recombinant PEGylated uricase for the treatment of severe gout; PRX–119, a plant cell-expressed long action DNase I for the treatment of NETs-related diseases; and others. Protalix has partnered with Chiesi Farmaceutici S.p.A., both in the United States and outside the United States, for the development and commercialization of pegunigalsidase alfa.

SOURCE: Protalix BioTherapeutics