ALX-0681-2.1/10 Protocol Version 2.0

• Research type

  Research Study

• Full title

  A Phase II single blind, randomized, placebo controlled trial to study the efficacy and safety of anti-von Willebrand factor Nanobody administered as adjunctive treatment to patients with acquired thrombotic thrombocytopenic purpura.

• IRAS ID

  57834

• Contact name

  Marie Scully

• Sponsor organisation

  Ablynx

• Eudract number

  2010-019375-30

• ISRCTN Number

  isrctn

• Research summary

  This is a Phase 2 study which will be conducted to see if ALX-0081 at the doses and schedule in this study are safe, tolerable (has few side effects) and effective in Acquired Thrombotic Thrombocytopenic Purpura. ALX-0081 is a nanobody. This is part of an antibody that has been genetically engineered to target von Willebrand factor (vWF) and inhibit its interaction with platelets. This selectively prevents blood clot formation in high-shear blood vessels. The study drug will be administered to patients in addition to their usual treatment for this disease. Their current treatment will proceed according to guidelines at the study site. The study aims to recruit 110 patients in approximately 30 sites. The patients will include symptomatic patients with acute episodes of idiopathic thrombotic thrombocytopenic purpura (TPP) as well as secondary TPP syndrome in association with plasma exchange. Patients will be randomised in a 1:1 ratio to receive either ALX-0081 or placebo in addition to plasma exchange. Patients will receive a first intravenous injection of study drug before plasma exchange and subsequent subcutaneous (under the skin) injections once or twice daily for the duration of plasma exchange and for 30 days following the last plasma exchange. Maximum treatment duration is 90 days after the patient first received study drug. Safety, efficacy and tolerability will be measured at intervals throughout the study. Patient will be followed for relapses for up to 1 year.

• REC name

  London - Harrow Research Ethics Committee

• REC reference

  10/H0709/60

• Date of REC Opinion

  26 Nov 2010

• REC opinion

  Further Information Favourable Opinion