BioMarin has reported positive results from the latest study of its haemophilia gene therapy valoctocogene roxaparvovec.
Haemophilia is a chronic condition that ordinarily requires lifetime blood transfusions. It is very costly to treat with limited results for patients.
Successful one-time gene therapies could be life-changing for people living with haemophilia by restoring the underlying cause of the disease and eliminating the need for regular infusions.
Haemophilia A mostly affects men and is about four times as common as haemophilia B. The types of disease are distinguished by the absence of particular blood clotting factors, factor VIII and factor IX respectively.
BioMarin has released three-year results from the phase 1/2 study revealing its one-time gene therapy enables patients to produce their own factor VIII.
According to the company, bleeding episodes for the seven patients who received the optimal dose of its gene therapy dropped from a median of 16.5 per year to none.
The patients no longer required blood transfusions. This was down from an average of 139 per year.
BioMarin also updated on evidence from a phase 3 trial measuring the enduring effect of its gene therapy. It showed a decline in the levels of the factor VIII protein over three years. The decline plateaued between years two and three and the company said the study had met the criteria to submit to the accelerated registration pathways of the US and European regulators.
Extrapolation of the results suggested the benefit of factor VIII production could persist for up to eight years and maybe even a lifetime. However, the therapy has already demonstrated a marked improvement in the quality of life for haemophilia A patients compared to current chronic treatments.
Spark Therapeutics, recently acquired by Roche, also has gene therapies for haemophilia A and B in development.
BioMarin confirmed they plan to bring the therapy to Australia.
Dr Amanda Ruth