Median times to partial success were similar between primary and rescue ITI cohorts in the G-ITI study, with about one-third of patients receiving ITI therapy for >3 years. In summary, data from the G-ITI study (41 cases of primary ITI, 19 cases of rescue
ITI) have demonstrated success rates (complete and partial) of 87% and 74% in primary and rescue ITI, respectively, with 85% of poor prognosis patients achieving success. G-ITI is the largest international multicentre ITI study using a single pdFVIII/VWF product. Response rates in children and adults undergoing primary or rescue ITI therapy, and in patients with risk factors for poor ITI response, are highly encouraging. A peak titre >200 BU mL−1 and a titre >50 BU mL−1 at the start of treatment were clearly negatively related to outcome, whereas age at start of ITI and find more time between diagnosis of inhibitor and start of ITI were not associated with outcome. S. K. AUSTIN E-mail: [email protected] International consensus guidelines state that
“Factor VIII/VWF concentrates are currently recommended for second-line and salvage ITI in patients who have failed previous attempts at tolerization using monoclonal or recombinant FVIII products” [13, 15]. In addition to these consensus guidelines, there is a growing wealth of scientific and clinical data to support the international consensus guideline statement. It is well established that 20–30% of patients with severe haemophilia who receive on-demand or prophylactic FVIII treatment will develop inhibitors. These patients selleck kinase inhibitor can be offered buy Ibrutinib ITI therapy
with the aim of becoming tolerized and returning to FVIII prophylaxis. In reality, however, some patients fail to tolerize and should be considered for tolerization with an alternative FVIII product, a strategy known as rescue ITI. With regard to rescue ITI, it is important to understand the definitions of success and failure. Current consensus defines ITI success as restoration of normal pharmacokinetic parameters, including an expected FVIII recovery >66%, an expected elimination half-life (t½) ≥6 h [11] or ≥7 h [11, 16, 17], or, a measurable FVIII trough level after 48 h with a 50 IU kg−1 dose [17]. Partial response can be classified as a stable and good clinical response to FVIII without an anamnestic rise in inhibitor titres but with abnormal pharmacokinetic parameters [11, 17]. Failure can be defined as the failure to achieve tolerization within 33 months or, more specifically, failure to achieve a 20% reduction in inhibitor titre over any 6-month period after the first 3 months [11, 16-18]. If the success of ITI is classified in this manner, patients demonstrating success are theoretically handling their FVIII normally.