CONTRARY to previous beliefs, researchers have found no significant differences in the effectiveness of immune tolerance induction (ITI) therapy across different racial and ethnic groups in individuals living with haemophilia A.
Haemophilia A is a genetic disorder characterised by a deficiency in clotting factor VIII. Consequently, patients may experience excessive bleeding, occurring either spontaneously or following trauma or surgical procedures. Factor replacement therapies can help prevent or manage bleeding episodes by supplying the deficient clotting protein, but certain patients may develop inhibitors against the administered protein, impeding its functionality.
ITI therapy is designed to counteract this response by administering incremental doses of a clotting protein; this trains the immune system not to recognise the protein to be a threat. Through this process, the adapts to tolerate the clotting protein, halting the production of neutralising antibodies against it.
People of Black or Hispanic origin with haemophilia were said to be more likely to develop inhibitors against the clotting protein. This led researchers from the Emory University School of Medicine, Atlanta, Georgia, USA, to review the data of 500 people with haemophilia A, from different ethnic backgrounds, aged 3 years or above, who underwent ITI and developed inhibitors against factor VIII at a median age of 2 years.
The study involved a diverse patient population, including 56.9% non-Hispanic White people, 19.1% non-Hispanic Black people, 18.1% Hispanic people, 4.5% Asian people, and those missing race and ethnicity data coded as other. Before ITI, most patients exhibited low inhibitor levels, indicating a higher likelihood of treatment success. Of those undergoing ITI, over half (59.8%) achieved successful outcomes, while 20.8% experienced partial success and 19.5% had ITI failure, necessitating bypassing agents to keep bleeding under control. Interestingly, the success rates of ITI did not significantly differ among racial and ethnic groups, with percentages of successful ITI comparable across different racial and ethnic backgrounds when prognosis levels were similar, as noted by the researchers.
The team said a misperception about the likelihood of success of ITI could influence or weaken a doctor’s recommendation but added that their “findings may guide future ITI discussions and dispel beliefs of lower success rates among minoritised racial and ethnic groups.”
