The European Medicines Agency (EMA) has validated a regulatory application seeking approval for a less frequent dosing regimen of Elfabrio (pegunigalsidase alfa) for adult patients with Fabry disease. This enzyme replacement therapy (ERT), co-developed by Chiesi Global Rare Diseases and Protalix Biotherapeutics, is currently administered every two weeks. If approved, the new regimen would allow for infusions once every four weeks at a dose of 2 mg/kg, instead of the current 1 mg/kg every other week.
Giacomo Chiesi, executive vice president of Chiesi Global Rare Diseases, stated that the validation is an "important milestone" in their efforts to reduce the treatment burden for Fabry patients with unmet medical needs. The application is based on data from the Phase 3 BRIGHT clinical trial (NCT03180840) and its ongoing open-label extension study (NCT03614234).
Supporting Data from BRIGHT Trial
The BRIGHT trial involved 30 Fabry patients previously treated with other ERTs on a bi-weekly schedule. Results indicated that Elfabrio administered every four weeks was generally safe and effective after one year. Dror Bashan, president and CEO of Protalix, believes the new regimen offers a beneficial alternative for some Fabry patients.
Fabry disease is a rare genetic disorder caused by a deficiency in the alpha-galactosidase A (alpha-Gal A) enzyme, leading to the accumulation of globotriaosylceramide (Gb3) in cells. This buildup progressively damages organs, including the kidneys, heart, and nervous system, resulting in a range of symptoms. ERT has been the standard treatment for over two decades, delivering a functional alpha-Gal A enzyme to break down Gb3 and slow disease progression.
Elfabrio's Modified Enzyme and Clinical Outcomes
Elfabrio is an ERT modified to enhance enzyme stability and prolong its presence in the bloodstream. The BRIGHT study assessed the safety of a less frequent, higher dose regimen in patients with stable disease on other ERTs. The data showed that Elfabrio, when administered every four weeks at 2 mg/kg, maintained effective levels in the bloodstream throughout the interval. Kidney function and Fabry disease markers remained generally stable over the one-year treatment period.
Approximately one-third of participants experienced mild to moderate side effects, and the alternative dosing regimen was considered well-tolerated overall. Patients who completed the BRIGHT trial could enroll in an open-label extension study to evaluate the long-term safety, tolerability, and efficacy of the less frequent dosing, with treatment lasting up to seven years and the study concluding in 2026.
Bashan added, "Together with Chiesi, we remain committed to meeting the needs of people with Fabry disease and bringing additional therapeutic options to market."
