The German Registry of immune tolerance treatment in hemophilia--1999 update.

As of 1999, the German registry of immune tolerance treatment in hemophilia has received reports on 146 patients who have undergone this therapy from 25 hemophilia centers. In 16 of the reported patients treatment is ongoing. Therapy has been completed in 126 patients of all groups with hemophilia A; most of them are children. In 78.6% of hemophilia A patients full success was achieved, 8.7% finished with partial success, and in 12.7% ITT failed. Statistical analysis demonstrates that interruptions of therapy have a negative influence on success. The inhibitor titer has the highest predictive value for success or failure of therapy. A high maximum titer as well as a high titer at start of treatment were related to a low success rate. Other variables such as exposure days and time interval between inhibitor detection and start of ITT were not statistically significant. Four patients with hemophilia B have also completed therapy, only one of them with success.