Hemostatic Challenges In Patients Treated with Eltrombopag

Chronic immune thrombocytopenia (ITP) is an autoimmune disease in which antiplatelet-antibodies induce platelet destruction and impair platelet production, resulting in chronically low platelet counts. Patients with chronic ITP may require invasive procedures associated with bleeding (hemostatic challenges) that cannot be undertaken if the platelet count is unacceptably low. Eltrombopag is an oral, nonpeptide, thrombopoietin receptor (TPO-R) agonist developed to increase platelet counts in various conditions associated with thrombocytopenia; its use may facilitate undertaking invasive procedures in patients with chronic ITP, reducing the need for additional supportive requirements including cellular blood products.

Across the eltrombopag ITP clinical trials, information about hemostatic challenges was collected retrospectively (TRA100773A and B) and prospectively (REPEAT, RAISE, EXTEND). Basic demographic information, platelet counts before and after the procedures, type of procedure, need for additional treatment to increase platelet counts (one week before and after the intervention), use of blood products, and where possible, assessment of bleeding and bleeding complications were recorded. For the purpose of this analysis, minor invasive procedures (eg, dental cleaning, endoscopy, bone marrow biopsy) were distinguished from major invasive procedures (splenectomy, laparotomy, hip replacement, aortic aneurysm repair, arthroplasty).

Seventy-seven patients underwent 120 invasive procedures while enrolled in clinical trials with eltrombopag. The median age of patients undergoing invasive procedures was 54 years; the median duration of treatment at the time of all procedures was 131 days. 112 invasive procedures were performed in patients while receiving eltrombopag, compared to 8 procedures among patients while receiving placebo. 65 (54%) were considered to be major and 55 (46%) were considered to be minor. The median platelet count closest to minor or major invasive procedures in patients receiving eltrombopag was higher than in those receiving placebo (Table). For minor procedures, rescue ITP medication was required in 9/52 (17%) procedures in patients treated with eltrombopag and in 1/3 (33%) procedures in patients receiving placebo. For major procedures, rescue ITP medication was required in 14/60 (23%) procedures in patients treated with eltrombopag and 3/5 (60%) procedures in patients receiving placebo. One bleeding complication was reported in an eltrombopag-treated patient with colon cancer who, on the first post-operative day after a colectomy, experienced a pulmonary embolism requiring anticoagulation and had an intra-abdominal hemorrhage on post-operative day 2.

No difference in use of periprocedural blood products between groups was discernable, possibly due to the low frequency of bleeding events reported. Although the number of patients who did not undergo procedures due to thrombocytopenia was not captured, data from 77 patients undergoing 120 invasive procedures suggest that by achieving a sustained platelet increase in patients with chronic ITP, eltrombopag facilitates the undertaking of medical and surgical procedures associated with bleeding.

Tarantino: GlaxoSmithKline, Novo Nordisk, Talecris, Baxter, Cangene: Honoraria, Research Funding, Speakers Bureau. Fogarty: GlaxoSmithKline: Honoraria, Research Funding. Mayer: GlaxoSmithKline: Employment, Equity Ownership. Vasey: GlaxoSmithKline: Employment. Brainsky: GlaxoSmithKline: Employment.