BackgroundLittle information regarding the management of invasive procedures in people with hemophilia B (HB) after undergoing gene therapy is available. Here, we report the management of invasive procedures in people with severe or moderately severe HB who had previously been treated with etranacogene dezaparvovec in the phase 2b and phase 3 HOPE-B clinical trials (NCT03489291 and NCT03569891). Objectives▪. MethodsThis retrospective analysis included invasive procedures performed within 3 and 2 years following a single infusion of 2 × 1013 gc/kg of etranacogene dezaparvovec in participants in the phase 2b and HOPE-B trials, respectively. Data for factor (F)IX dosing, duration of postoperative FIX use, FIX activity prior to invasive procedures, and postoperative bleeds were collected and analyzed. ResultsThe analysis included 64 procedures in 29 participants: 9 major surgeries, 24 minor surgeries, 11 endoscopies, 3 endoscopies with biopsy/polypectomy, and 17 dental procedures. Uncontaminated endogenous FIX activity corresponded to mild hemophilia or normal levels prior to 98% of all procedures, with a median endogenous FIX activity of 43.8 IU/dL (range, 3.1-113 IU/dL). All major surgeries were managed with exogenous FIX, 67% with ≤4 days of FIX infusion. Most minor surgeries (88%), endoscopies (82%), and dental procedures (94%) were managed with no or a single FIX infusion. Postoperative bleeds occurred after 1 minor surgery and 4 dental procedures. There were no symptomatic thrombotic events or FIX inhibitor developments. ConclusionEtranacogene dezaparvovec has the potential to facilitate perioperative management in people with HB by reducing the need for perioperative exogenous FIX and its associated risks.
Read full abstract