aTTP is caused by autoantibody inhibition of the ADAMTS13 enzyme (a von Willebrand factor-cleaving protease),2 which leads to:

  • Impaired cleavage of ultra-large von Willebrand factor (ULvWF) multimers released from the endothelium1
  • Platelets spontaneously adhering to ULvWF through the platelet membrane protein GPIb3
  • vWF-platelet aggregates causing the formation of microthrombi1
    1. Joly B, Coppo P and Veyradier A. Blood. 2017;129(21):2836–2846.
    2. Sadler JE. Blood. 2008;112(1):11–18.
    3. Peyvandi F, Garagiola I and Baronciani L. Blood Transfus. 2021;9(Suppl 2):s3–s8.

MAT-GB-2105170 (v1.0)
Date of preparation: April 2022