Protalix BioTherapeutics has found a path forward for resubmitting an application for a Fabry disease medicine with the FDA; it’s just going to take a while.
The Israeli biotech received a complete response letter from the FDA for PRX–102, or pegunigalsidase alfa, in April, which iced the company’s plan to see the therapy through to a swift approval. The agency did not have any complaints about the safety of the therapy but said an inspection of Protalix’s manufacturing facility in Karmiel, Israel, had to be completed. The inspection was unable to be conducted due to COVID-19 travel restrictions.
Another issue is that the drug PRX–102 is being compared to in the clinical trial, Sanofi’s Fabrazyme, has now been fully approved. That puts into questions whether Protalix’s follow-on therapy can be approved under an accelerated pathway since patients now have a fully approved option.
After a meeting with the biotech, the FDA has agreed that Protalix has an adequate data package to support a traditional approval of PRX–102 in Fabry disease, according to a Monday update.
But that data package includes the final two-year analysis of a phase 3 clinical trial called BALANCE, which as of June is ongoing. While executives did not specifically note the timeline for resubmission, the BALANCE trial is expected to be completed in May 2022, according to the FDA’s clinical trial tracker. Protalix has two extension studies of PRX–102 also listed on the tracker with completion dates of September 2022 and January 2023.
Protalix is working with Chiesi Global Rare Diseases, a business unit of Chiesi Farmaceutici, on PRX–102 in Fabry disease, a rare metabolic disorder that causes episodes of severe burning pain and can eventually lead to kidney failure or cardiac disease. Should the drug be approved, Protalix will receive a milestone payment from Chiesi.
The companies submitted the Biologics License Application for accelerated approval of PRX–102 back in May 2020. The therapy was granted a fast-track tag from the FDA in 2018.
While the FDA resubmission chugs along, Protalix plans to submit a marketing submission for the EU in the first quarter of 2022.
Protalix shares dropped just over 10% in early morning trading to $1.18, compared to a previous close of $1.30. Prior to the complete response letter, the company’s shares were trading around $6 apiece.