IdeS in Asymptomatic Antibody-Mediated Thrombotic Thrombocytopenic Purpura (TTP) Patients
IdeS in Asymptomatic Antibody-Mediated Thrombotic Thrombocytopenic Purpura (TTP) Patients
The main purpose of this study is to evaluate safety and tolerability in patients diagnosed
 with asymptomatic antibody-mediated TTP with low ADAMTS13 activity after receiving single
 intravenous dose of IdeS.
Immunoglobulin G-degrading enzyme of Streptococcus pyogenes (IdeS) is an IgG specific
 endopeptidase which cleaves IgG molecules and efficiently neutralizes Fc-mediated activities.
 IdeS-mediated IgG degradation constitutes a novel therapeutic principle for the treatment of
 IgG-driven human diseases.

 In addition to assessing the safety and tolerability of IdeS the study will also assess the
 efficacy of IdeS to significantly increase the ADAMTS13 activity and decrease the
 anti-ADAMTS13 antibody levels in patients diagnosed with asymptomatic antibody-mediated TTP
 with low ADAMTS13 activity.
Inclusion Criteria:

 -  Age 18 years or above

 -  Diagnosed with acquired TTP with ADAMTS13 levels of ≤ 10 % in clinical remission and
 with measurable or previously confirmed ADAMTS13 antibodies

 Exclusion Criteria:

 -  Prior malignancy within 5 years

 -  Test positive for serum hepatitis B surface antigen, hepatitis C antibody and human
 immunodeficiency virus (HIV)

 -  Ongoing infectious disease including P-CRP >10

 -  Test positive for IgE antibodies against IdeS

 -  Secondary cause of TTP

 -  Rituximab treatment or other antibody-based therapy within 7 days prior to IdeS dosing

 -  Treatment with investigational medicinal product within the last 12 weeks proceeding
 screening

 -  Severe other conditions requiring treatment and close monitoring, e.g. cardiac failure
 > NYHA (New York Heart Association) grade 3, unstable coronary disease or oxygen
 dependent COPD

 -  History of any other clinically significant disease or disorder which may either put
 the patient at increased risk because of participation in the study, or influence the
 results or the patient's ability to participate in the study

 -  Hypogammaglobulinemia defined as any values of P-total IgG less than 3 g/L

 -  History of severe allergy/hypersensitivity or ongoing allergy/hypersensitivity, or
 history of hypersensitivity to drugs with a similar chemical structure or class to
 IdeS (e. g. streptokinase and/or staphylokinase)

 -  Substance abuse or other concurrent medical condition that could confound study
 interpretation or affect the patient's ability to tolerate or complete the study

 -  Breast feeding women or women with a positive pregnancy test

 -  Previously received IdeS treatment