Study of FIX Prophylaxis Replacement Therapy on Haemophilia B and A Subjects
Research type
Research Study
Full title
An open-label, non-investigational product, multi-centre, lead-in study to evaluate prospective efficacy and selected safety data of current factor IX (FIX) or factor VIII (FVIII) prophylaxis replacement therapy in the usual care setting of moderately severe to severe adult haemophilia B participants (FIX:C≤2%) who are negative for neutralising antibodies to adeno-associated virus vector-spark100 (Benegene-1) and moderately severe to severe haemophilia A adult participants (FVIII:C≤1%) who are negative for neutralising antibodies to adeno-associated virus vector 6 (AAV6), prior to the respective therapeutic phase 3 gene therapy studies.
IRAS ID
248553
Contact name
Sirjana Gurung
Contact email
Sponsor organisation
Pfizer Inc.
Eudract number
2017-001271-23
Duration of Study in the UK
2 years, 0 months, 18 days
Research summary
Summary of Research
This study is being carried out to assess how effective current factor IX prophylaxis replacement therapy is in treating haemophilia B and also to determine if the participant’s body produces antibodies to a particular virus, specifically AAV-Spark 100.Patients with haemophilia B have defective factor IX genes. Gene therapy works by using a tool called a “vector” to transfer a normal or “working” factor IX gene into patient’s liver cells where factor IX is usually processed and excreted. The virus for gene therapy is modified so that once it delivers the factor IX gene to the liver cells it is no longer functional/infective and is broken down by the liver cells.
AAV-Spark 100 will be used in study (C0371002) as the vector in an experimental gene therapy treatment to deliver a copy of the factor IX gene to a patient with haemophilia B allowing the body to start producing the body’s own factor IX without the need to replace factor IX externally through blood infusions. It is important to evaluate if the participants have antibodies to AAV-Spark100. When a person gets infected with a naturally occurring virus such as the cold virus, the body usually responds by making proteins called antibodies, which act to prevent infections in case the participants are exposed to the same virus again. If the participants have antibodies to AAV-Spark 100, they will block AAV-Spark 100 from delivering the factor IX gene to their liver cells, making the treatment with this experimental gene therapy for haemophilia B ineffective.
The information collected in this study (C0371004) will be used to assess how effective gene therapy is in a subsequent research study (C0371002) should they choose to enter and meet eligibility requirements. There is no investigational study drug being used for this study. Participants will continue to administer their current factor IX replacement therapy as prescribed by their doctor as part of standard care. Approximately 110 participants will be screened and 55 participants (who have been tested negative for antibodies prior to the study) will be enrolled at approximately 50-60 research sites or clinics in approximately 20 countries throughout the world. The duration of this study is planned for a minimum of seven months (including screening period). The study is being sponsored by Pfizer.
Summary of Results
The summary of results will be published here: https://eur03.safelinks.protection.outlook.com/?url=https%3A%2F%2Ftrack.pstmrk.it%2F3ts%2Fwww.pfizer.com%252Fscience%252Fclinical-trials%252Fplain-language-study-results-summaries%2FNBTI%2FWqm9AQ%2FAQ%2Fbb997c56-c457-476e-8b49-fbe4a5e45bc6%2F1%2FZAS2toJL31&data=05%7C02%7Capprovals%40hra.nhs.uk%7Cf4e4ea7e5e9f4bfceb1a08dd9eb2959a%7C8e1f0acad87d4f20939e36243d574267%7C0%7C0%7C638841212062028456%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C0%7C%7C%7C&sdata=7kxmIrbK8nC4plIiy3ypXLGoTCgABYzLs5B0D1oVkDY%3D&reserved=0• US and EU Basic Results will be available around (or 1-2 working days later than) 19 Sep 2025 and 15 Oct 2025, respectively.
• Plain Language Study Results Summary will be available by 21 Aug 2025 (or earlier)REC name
Scotland B REC
REC reference
18/SS/0144
Date of REC Opinion
22 Mar 2019
REC opinion
Further Information Favourable Opinion