BioMarin Pharmaceutical has dosed the first patient in a Phase lll study of valoctocogene roxaparvovec (formerly BMN 270) gene therapy to treat patients with severe haemophilia A.

Hemophilia A is also known as factor VIII (FVIII) deficiency or classic haemophilia, and is a genetic disorder caused by missing or defective factor VIII, a clotting protein.

The new trial is the first of two Phase lll studies in the global Phase lll programme of valoctocogene roxaparvovec.

The global programme features two studies with valoctocogene roxaparvovec, one with the 6e13vg/kg dose (GENEr8-1) and the other with the 4e13vg/kg dose (GENEr8-2).

“Valoctocogene roxaparvovec has received US FDA breakthrough therapy designation.”

Both the open-label single-arm studies will evaluate the efficacy and safety of valoctocogene roxaparvovec.

GENEr8-2 trial expects to enrol the first patient at the beginning of next year. Its primary objective of both studies will be based on the FVIII activity level achieved after valoctocogene roxaparvovec, while the secondary endpoints will determine annualised FVIII replacement therapy use rate and annualised bleed-rate.

The valoctocogene roxaparvovec has received US Food and Drug Administration’s (FDA) breakthrough therapy designation, which seeks to facilitate and expedite development and review new drugs to address an unmet medical need to treat the serious condition.

In addition, BioMarin will initiate a Phase l/ll study with the 6e13kg/vg dose and enrol ten patients who are AAV5-positive. The first patient for the trial is expected to be enrolled in the first half of next year.