Phase 1 Dose Escalation, Single Dose Study to Assess Safety and Pharmacokinetics of BAX930 in Hereditary Thrombotic Thrombocytopenic Purpura (TTP)

Inclusion Criteria:

- Subject is between 12 and 65 years of age, inclusive. (The first 2 subjects in any
cohort will be ≥ 18 years of age.)

- Subject and/or legally authorized representative has provided written informed
consent.

- Subject has a documented diagnosis of severe hereditary ADAMTS13 deficiency, defined
as 1) confirmed by genetic testing, documented in patient history or at screening, and
2) ADAMTS13 activity < 6%, documented in patient history or at screening. NOTE: In
patients receiving prophylactic therapy with fresh frozen plasma (FFP) or other
ADAMTS13 containing products, the levels of plasma ADAMTS13 activity may exceed 6% at
screening.

- Cryoprecipitate, FFP, or other ADAMTS13 containing products interfering with ADAMTS13
PK have to be paused at least 10 days prior to infusion of the investigational
product.

- The subject is not displaying any severe TTP symptoms at screening. Patients
presenting with minor, but stable laboratory abnormalities (LDH not higher than 3
times the upper limit of normal; platelet count not lower than 100,000 per μl) at
screening may be enrolled.

- Subjects ≥18 years of age have a Karnofsky score ≥ 60%, and subjects < 18 years of age
have a Lansky score ≥ 70%.

- Subject is hepatitis C virus negative (HCV-) as confirmed by antibody or polymerase
chain reaction (PCR) testing; HCV positive (HCV+) subjects are eligible for inclusion
if their disease is chronic but stable.

- If female of childbearing potential, subject presents with a negative serum pregnancy
test and agrees to employ adequate birth control measures for the duration of the
study.

- Subject is willing and able to comply with the requirements of the protocol.

Exclusion Criteria:

- Subject has been diagnosed with any other TTP-like disorder (for example,
microangiopathic hemolytic anemia), including acquired TTP.

- Subject has known hypersensitivity to hamster proteins or other components of the
investigational product.

- Subject has a medical history or presence of a functional neutralizing ADAMTS13
inhibitor at screening.

- Subject has a medical history of immunological disorders, excluding seasonal allergic
rhinitis/conjunctivitis/mild asthma, food allergies or animal allergies.

- Subject has a medical history of hematological disorders, in particular systemic lupus
erythematosus, amyloidosis, antiphospholipid antibody syndrome, vasculitis, other
hemolytic anemia, disseminated intravascular coagulation, and systemic scleroderma.

- Subject has a history of significant neurological events, such as major stroke,
indicating that a relapse might have severe consequences, as judged by the
investigator.

- Subject is HIV positive with an absolute CD4 count < 200/mm3.

- Subject has been diagnosed with a cardiovascular disease [New York Heart Association
(NYHA) classes 3-4].

- Subject is scheduled to undergo elective surgery during study participation.

- Subject has been diagnosed with severe liver disease, as evidenced by, but not limited
to, any of the following: serum ALT 3 times the upper limit of normal, international
normalized ratio (INR) > 1.5, hypoalbuminemia, portal vein hypertension (e.g. presence
of otherwise unexplained splenomegaly, history of esophageal varices).

- Subject has been diagnosed with severe glomerular disease, with gross proteinuria and
a serum creatinine level ≥ 2.5 mg/dL.

- Subject has been treated with an immunomodulatory drug, in case of corticoids with an
equivalent to hydrocortisone greater than 10 mg /day, excluding topical treatment
(e.g. ointments, nasal spray), within 30 days prior to enrollment.

- Subject has a history of drug and/or alcohol abuse within the last 6 months prior to
study enrollment.

- Subject has a life expectancy of less than 3 months.

- Subject is identified by the investigator as being unable or unwilling to cooperate
with study procedures.

- Subject is a family member or employee of the investigator.

- Subject suffers from a mental condition rendering him/her unable to understand the
nature, scope and possible consequences of the study and/or evidence of an
uncooperative attitude.

- If female, subject is pregnant or lactating at the time of study enrollment.

- Subject has participated in another clinical study involving an investigational
product or device within 30 days prior to study enrollment.

- Subject is scheduled to participate in another clinical study involving an
investigational product or device during the course of this study.