Protalix's Gaucher Drug May Fill Gap Left from Genzyme Plant Closure

Protalix BioTherapeutics (Carmiel, Israel) said the US Food and Drug Administration has asked the company to consider submitting a treatment protocol for the use of prGCD, the company’s development drug for patients with Gaucher disease, to address an expected shortage of Genzyme’s Cerezyme. Genzyme recently halted production of Cerezyme to sanitize its plant in Allston Landing, MA, because of virus contamination of a bioreactor.

According to the announcement, the FDA believes the company’s development program for prGCD satisfies the regulatory criteria required to supply prGCD for expanded access to patients under a treatment protocol. Under current FDA regulations, a treatment protocol may be submitted for a drug in clinical development that has not yet been approved to treat a serious or life threatening disease for which no comparable or satisfactory alternative drug or therapy is available. Protalix’s prGCD is recombinant glucocerebrosidase enzyme expressed in plant cells, and is about to enter Phase 3 clinical trials.

Genzyme’s Cerezyme is the only enzyme replacement therapy currently approved for Gaucher disease. Genzyme halted production of Cerezyme in mid-June after discovering that a bioreactors used to produce Cerezyme had been contaminated with Vesivirus, a virus that interferes with the growth of Chinese hamster ovary cells but is not known to infect humans. Following a complete disinfection of the plant, Genzyme expects to resume production by the end of July. Product shortages as a result of the plant shutdown are expected to last approximately 6 to 8 weeks, beginning in August for Cerezyme, and in October for Fabryzme, another product made at the plant.

Protalix and the FDA are discussing the parameters of a proposed treatment protocol that would allow an increased number of patients with Gaucher disease to have access to prGCD. The company said it expects to submit a treatment protocol to the FDA for its review as a supplement to the company’s current Investigational New Drug (IND) application for prGCD.

Genzyme, meanwhile, is working with regulatory authorities, physicians, and patient organizations to manage product supply, including collaborating with the National Gaucher Foundation’s medical advisory board to formulate clinical guidelines for physicians to following during the shortage.

Previous coverage:
Genzyme Recalls Fabrazyme 5 mg
Jun 30, 2009

Genzyme Detects Virus Contamination of Bioreactor, Halts Production
Jun 17, 2009