Immune Tolerance

If left unchecked, a persistent inhibitor will present a severe burden on patients and families, as the ongoing physical, emotional and, in many cases financial toll, continues to intensify. It is therefore simply not enough to treat episodic bleeds in the midst of a high responding inhibitor and experience the ongoing stress associated with “survival mode.” Instead healthcare providers will often attempt to proactively stamp out an inhibitor through immune tolerance therapy (ITI).

ITI is an approach to inhibitor eradication whereby the body’s immune system begins to tolerate a therapy after daily doses of factor are administered over time. Individuals who undergo ITI will receive daily doses of factor over a period of weeks, months, or in some cases, years. These patients may also be prescribed immune suppressive drugs, which can predispose one to infections. As with any new treatment regimen, including adjunct medications, the risks and benefits should be part of a discussion between the patient and their healthcare provider.

Overall, ITI sees greater success in hemophilia A then in hemophilia B. Approximately 70% of patients with hemophilia A and inhibitors will become tolerated through ITI, while the success rate for hemophilia B is around 30%.