Photo by Julia Koblitz on Unsplash (illustrative)
On 9 December 2024, researchers at Christian Medical College Vellore in India published results of a gene therapy for severe hemophilia A in the New England Journal of Medicine. The study, funded by India's Ministry of Science and Technology and others, used the patients' own blood stem cells, modified to produce clotting factor VIII.
Key facts
Five men aged 22 to 41 with severe hemophilia A were treated at a single center.
Their stem cells were given a new factor VIII gene using a lentiviral vector and returned after chemotherapy conditioning.
The annual bleeding rate was zero for all five over a combined 81 months of follow-up (median 14 months).
Factor VIII levels stayed stable, reaching about 19 to 40 IU per deciliter in the three patients whose cells were made with an improved method.
Why it matters
Severe hemophilia A is usually managed with repeated factor VIII replacement or other products to stop or prevent bleeding. A one-time treatment that lets the body make its own clotting factor, developed and tested in India, shows that advanced gene therapy can be built outside the richest countries.
Worth noting
This is a five-person study with short follow-up and no statistical analysis. The treatment requires chemotherapy to make room for the modified cells, which carries risks, and larger trials are needed.