Benzinga | Jul 21, 2021 12:00PM EDT

Spark Therapeutics' Hemophilia Gene Therapy Achieve Stable, Durable FVIII Expression

* Spark Therapeutics, a unit of Roche Holdings AG (OTC:RHHBY), has announced updated data from the ongoing Phase 1/2 trial of SPK-8011 gene therapy in hemophilia A.

* Data were presented at the International Society of Thrombosis and Hemostasis (ISTH) 2021.

* These data demonstrated that administration of SPK-8011 resulted in sustained factor VIII (FVIII) expression in 16 of 18 participants with up to 4 years of follow-up, as of the May 3, 2021 data cutoff.

* Eighteen participants in the Phase 1/2 trial received a single administration of investigational SPK-8011 in four dose cohorts, ranging from 5x1011 vg/kg to 2?1012 vg/kg. In the 16 patients with sustained FVIII expression, there was a 91.2% reduction in annualized bleed rate (ABR) and a 97% reduction in annualized FVIII infusion rate (AIR) after vector administration.

* SPK-8011 showed an acceptable safety profile with no deaths and no FVIII inhibitor development with up to 4 years of follow-up.

* Price Action: RHHBY shares are up 0.89% at $48.51 during the market session on the last check Wednesday.