severe hemophilia A
About
Hemophilia A is caused by a mutation in the F8 gene that leads to a deficiency of coagulation factor VIII and is X-linked recessive inheritance. Severe patients (FVIII<1%) have frequent spontaneous bleeding, and repeated joint bleeding leads to joint disease and disability. Core dilemmas: ① Frequent intravenous infusions of FVIII are required throughout life (preventive treatment 2-3 times a week);②25-30% of patients develop inhibitors (antibodies), resulting in treatment failure;③ Although gene therapy (Roctavian) has been approved, it is suitable for limited population and long-term efficacy remains to be observed.
Features & Symptoms
- FVIII factor activity <1%
- Spontaneous joint/muscle bleeding
- Recurrent joint disease disabling
- Intracranial hemorrhage can kill you
Treatment Options
| Treatment | Description | Stage | Price Range |
|---|---|---|---|
| Valoctocogene roxaparvovec（Roctavian） | The AAV5 vector delivers the FVIII gene with a B-domain deletion and will be approved by the FDA in 2023. FVIII activity can be maintained for several years after a single dose. | FDA批准 | $2.5M - $3M/次（一次性） |
| Emesizumab (Hemlibra) | Bispecific antibodies mimic FVIII function and are injected subcutaneously once a week/every two weeks/every four weeks for patients with inhibitors. | FDA批准 | $500K - $800K/年 |
| Long-acting FVIII factor replacement | PEGylated or Fc-fused long-acting FVIII can extend the dosing interval to once every 3-5 days. | FDA批准 | $300K - $600K/年 |
Prognosis
Modern preventive treatment can approach normal life spans, but joint lesions are still common
Additional Notes
Notes: FVIII inhibitor screening: Regularly tested for FVIII inhibitors before and after treatment, and patients with positive inhibitors need to switch to bypass factors (e.g. aPCC or rFVIIa); Gene therapy evaluation: Valoctacogene roxaparvovec (Roctavian) has been approved for use in adult patients with severe hemophilia A, and liver function and pre-existing AAV5 antibodies need to be evaluated; preventive treatment: whether or not gene therapy is received, a standardized preventive treatment plan should be established; joint assessment: Regular joint ultrasound or MRI should be performed to assess subclinical joint bleeding; Vaccination: Avoid intramuscular injection, and all vaccines should be injected subcutaneously.; Exclusive service commitment: The platform will allocate a dedicated medical team to each patient to assist in dismantling and properly deploying the following precautions throughout the process. When cross-state and cross-border diagnosis and treatment projects or drugs are involved, the platform will make overall arrangements for the entire docking; for disabled and semi-disabled patient groups, the platform will provide rush-free alternative solutions (including remote consultation, door-to-door sampling, direct drug delivery in the cold chain, etc.), to ensure that patients can get the same high-quality diagnosis and treatment resources without having to travel in person.; Study phase: FDA approval. Prognosis: Modern preventive treatment can approach normal life expectancy, but joint lesions are still common.
Frequently Asked Questions
What is severe hemophilia A?
Hemophilia A is caused by a mutation in the F8 gene that leads to a deficiency of coagulation factor VIII and is X-linked recessive inheritance. Severe patients (FVIII<1%) have frequent spontaneous bleeding, and repeated joint bleeding leads to joint disease and disability. Core dilemmas: ① Frequent intravenous infusions of FVIII are required throughout life (preventive treatment 2-3 times a week);②25-30% of patients develop inhibitors (antibodies), resulting in treatment failure;③ Although gene therapy (Roctavian) has been approved, it is suitable for limited population and long-term efficacy remains to be observed.
What are the symptoms of severe hemophilia A?
FVIII factor activity <1%,Spontaneous joint/muscle bleeding,Recurrent joint disease disabling,Intracranial hemorrhage can kill you
How is severe hemophilia A treated?
Valoctocogene roxaparvovec（Roctavian）: The AAV5 vector delivers the FVIII gene with a B-domain deletion and will be approved by the FDA in 2023. FVIII activity can be maintained for several years after a single dose.; Emesizumab (Hemlibra): Bispecific antibodies mimic FVIII function and are injected subcutaneously once a week/every two weeks/every four weeks for patients with inhibitors.; Long-acting FVIII factor replacement: PEGylated or Fc-fused long-acting FVIII can extend the dosing interval to once every 3-5 days.
What is the prognosis for severe hemophilia A?
Modern preventive treatment can approach normal life spans, but joint lesions are still common