Reduce coagulation factor demand 96% Hemophilia Type A gene therapy announces long-term clinical results

Patients with type A haemophilia have insufficient levels of factor VIII in the body due to mutations in the gene that encodes coagulation factor VIII (Factor VIII)For them, minor injuries can lead to pain and potentially life-threatening bleedingSevere haemophiliacs usually bleed spontaneously in their muscles and joints, which can cause permanent joint damageCurrently, the standard treatment for severe haemophilia type A is preventive intravenous factor VIIINot only do patients need treatment 2-3 times a week, but even if treated, bleeding events can still occur, which can have a significant impact on their quality of lifeValoctocogene roxaparvovec is a genetically modified gene therapy that uses AAV5 virus vectors to deliver expression factor VIIIThe advantage is that patients may only need to receive one treatment and liver cells can consistently express factor VIII, thus avoiding the need for long-term preventive coagulation factor injectionsThe treatment has been approved by the FDA for breakthrough therapy and THE EUROPEAN Union-awarded PRIME drug recognition, as well as the EMA and FDA-granted orphan drug qualificationDoubts about this gene therapy, however, are how long it will lastthe data reported at WFH are the latest data available as of 8 April 2020, including four-year data on patients receiving high-dose (6e13 vg/kg) gene therapy and 3 years of data for patients receiving low-dose (4e13 vg/kg) gene therapythe annual hemorrhage rate and coagulation factor VIII use in patients who received high-dose gene therapy
had an average annual hemorrhage rate (ABR) of 16.3 and a median of 16.5 in six previous studies of coagulation factor VIII prophylaxisDuring the four years following treatment, the cumulative average ABR was 0.8, a decrease of 95% from the baselineIn the fourth year, the average ABR was 1.3 and the median was 0The use of the average coagulation factor VIII decreased from 135.6 times per year to 5.4 times per year, a decrease of 96%86% (6/7) of all seven study subjects had no bleeding events in the fourth yearAll participants have not yet received propacuric treatment for coagulation factor VIII the annual hemorrhage rate and coagulation factor VIII use in patients treated with low-dose gene therapy
the average ABR was 12.2 and the median was 8.0 in the six study participants who received low-dose treatment During the three-year period observed, the cumulative average ABR decreased by 93% to 0.9 in 5 of the 6 subjects, and the jointcontinued without bleeding During the 3-year follow-up period, the average ABR was 0.5, the median was 0, and 5 of the 6 study participants had no spontaneous haemorrhage events Within three years, the use of average coagulation factor VIII decreased from 142.8 times per year at the baseline to 5.7 per year the level of coagulation factor VIII activity in patients all patients participating in clinical trials had a pre-treatment level of factor VIII activity of less than 1 IU/dL After 4 years of treatment with high dosegene gene therapy, the average factor VIII activity of the patient reached 24.2 IU/dL, and the median factor VIII activity reached 16.4 IU/dL (tested with hair color substrate) After 3 years of receiving low-dose gene therapy, the average level of factor VIII activity in patients reached 9.9 IU/dL, and the median factor VIII activity level was 7.9 IU/dL However, some analysts point out that factor VIII activity levels have declined somewhat each year for the past four years So how long the effects of this gene therapy can last will remain one of the focus of attention lead researcher in the clinical trial, Professor John Pasi of the Bartz and London School of Medicine and School of Dentistry, said: "This study represents the longest clinical experience of gene therapy for type A haemophilia Excitingly, all of the study participants stopped preventive treatment for coagulation factor VIII, while valocococogene roxaparvovec reduced bleeding events by more than 90 percent These data show the real potential of gene therapy to transform the treatment model for type A haemophilia, which may represent a new approach to addressing the highly unmet needs of severe haemophilia patients "