The following clinical trials for hemophilia A are currently active:

  • Safety and Dose Escalation Study of an Adeno-Associated Viral Vector for Gene Transfer in Hemophilia A Subjects (ClinicalTrials.gov Identifier: NCT03370172)
  • Gene Therapy Study in Severe Haemophilia A Patients  (ClinicalTrials.gov Identifier: NCT02576795)
  •  Single-Arm Study To Evaluate The Efficacy and Safety of Valoctocogene Roxaparvovec in Hemophilia A Patients (BMN 270-301) (ClinicalTrials.gov Identifier: NCT03370913)
  • Single-Arm Study To Evaluate The Efficacy and Safety of Valoctocogene Roxaparvovec in Hemophilia A Patients at a Dose of 4E13 vg/kg (BMN270-302) (ClinicalTrials.gov Identifier: NCT03392974)
  • Gene Therapy Study in Severe Haemophilia A Patients With Antibodies Against AAV5 (270-203) (ClinicalTrials.gov Identifier: NCT03520712)
  • Dose-Ranging Study of Recombinant AAV2/6 Human Factor 8 Gene Therapy SB-525 in Subjects With Severe Hemophilia A (ClinicalTrials.gov Identifier: NCT03061201)
  •  A Gene Transfer Study for Hemophilia A (ClinicalTrials.gov Identifier: NCT03003533)
  •  Long-Term Safety and Efficacy of SPK-8011 in Males With Hemophilia A (ClinicalTrials.gov Identifier: NCT03432520)
  •  Gene Therapy for Haemophilia A (GO-8) (ClinicalTrials.gov Identifier: NCT03001830)
  •  Gene Modified Stem Cells for Hemophilia A and B (ClinicalTrials.gov Identifier: NCT03217032)

Furthermore, the following clinical trials for hemophilia B are currently active:

  •  Gene Modified Stem Cells for Hemophielia A and B (ClinicalTrials.gov Identifier: NCT03217032)
  • Open-Label Single Ascending Dose of Adeno-associated Virus Serotype 8 Factor IX Gene Therapy in Adults With Hemophilia B (ClinicalTrials.gov Identifier: NCT01687608)
  • Ascending Dose Study of Genome Editing by Zinc Finger Nuclease Therapeutic SB-FIX in Subjects With Severe Hemophilia B (ClinicalTrials.gov Identifier: NCT02695160)
  • LTFU for Gene Transfer Subjects With Hemophilia B (ClinicalTrials.gov Identifier: NCT00515710)
  • A Gene Therapy Study for Hemophilia B (ClinicalTrials.gov Identifier: NCT02484092)
  • Long-term Safety and Efficacy Study of SPK-9001 in Individuals With Hemophilia B (ClinicalTrials.gov Identifier: NCT03307980)
  • Dose-Escalation Study Of A Self Complementary Adeno-Associated Viral Vector For Gene Transfer in Hemophilia B (ClinicalTrials.gov Identifier: NCT00979238)
  • Trial of AAV5-hFIX in Severe or Moderately Severe Hemophilia B (ClinicalTrials.gov Identifier: NCT02396342)
  • Dose Confirmation Trial of AAV5-hFIXco-Padua (ClinicalTrials.gov Identifier: NCT03489291)
  • A Factor IX Gene Therapy Study (FIX-GT) (FIX-GT) (ClinicalTrials.gov Identifier: NCT03369444)

Other strategies, such as combining gene and immunomodulatory therapies, are also being explored in murine models.

Despite the numerous studies underway, several barriers to successful AAV-based gene therapy persist. Some of these challenges include vector production concerns, transaminitis, hepatocellular carcinoma, and risk of insertional mutagenesis. Furthermore, multiple clinical trials have been stopped early, largely due to a lack of efficacy. However, no results from these studies have been reported, so a paucity of safety data remains.

Clinical Implications and Raising Awareness

Roland W Herzog, PhD, of the department of pediatrics at Indiana University in Indianapolis and coauthor of the study, told Hematology Advisor, “Awareness of the advantages of gene therapy for rare diseases such as hemophilia needs to mostly reach specialists.”

He continued, “A primary care doctor would refer a child diagnosed with hemophilia to a hemophilia treater. Patients with hemophilia have a very close relationship with their hemophilia doctor, and similar relationships exist for other genetic diseases.”

Regarding potential avenues of spreading awareness, Dr Herzog noted that “companies [investigating] gene therapies have various opportunities to [provide information] about their medicines at national meetings, as well as at meetings of disease foundations, which are attended by both physicians and patients. Furthermore, social media is a powerful way [that] patients, families, and disease foundations can [share] their experiences with gene therapy, thereby raising public awareness.”

Reference

1. Perrin GQ, Herzog RW, Markusic DM. Update on clinical gene therapy for hemophilia. Blood. 2019;133:407-414. doi: 10.1182/blood-2018-07-820720