A Study of Recombinant Von Willebrand Factor (rVWF) With or Without ADVATE in Children With Severe Von Willebrand Disease (VWD)

Inclusion Criteria:

• Diagnosis of severe von Willebrand disease (VWD) (defined as von Willebrand factor:ristocetin cofactor [VWF:RCo] less than [<] 20 percent [%]):

• Type 1 (VWF:RCo <20 International Units per deciliter [IU/dL]); or

• Type 2A (VWF:RCo <20 IU/dL), Type 2B (as diagnosed by genotype), Type 2N (Factor VIII coagulation activity [FVIII:C] <10 % and historically documentedgenetics), Type 2M; or

• Type 3 (VWF:Ag less than or equal to [=<] 3 IU/dL).

• Age 0 to <18 years at the time of Screening.

• The participant has provided assent (if appropriate) and legally authorizedrepresentative(s) has provided informed consent.

• If female of childbearing potential, participant presents with a negative serumpregnancy test.

• If applicable, participant agrees to employ adequate birth control measures for theduration of the study.

• The participant and/or the legally authorized representative are willing and able tocomply with the requirements of the protocol, which should also be confirmed basedon a pre-screening evaluation held between the Investigator and the Sponsor, toensure no eminent risk is present that could challenge the participants compliancewith the study requirements.

Additional inclusion criteria for both previously treated participants and participants undergoing surgery are as follows:

• Unable to tolerate or are inadequately responsive to deamino-delta-D-argininevasopressin (DDAVP).

• The participant has had a minimum of 1 documented bleed requiring VWF coagulationfactor replacement therapy (i.e. treatment with a VWF product) during the previous 12 months prior to enrollment and overall historically 3 or more exposure days (EDs)to VWF replacement therapy.

Additional inclusion criterion for previously untreated participants are as follows:

• The participant has not received prior VWF coagulation factor replacement therapy.

Exclusion Criteria:

• Diagnosis of pseudo-VWD or another hereditary or acquired coagulation disorder (eg,qualitative and quantitative platelet disorders or elevated prothrombin time [PT]/international normalized ratio [INR] greater than [>] 1.4).

• History or presence of a VWF inhibitor at Screening.

• History or presence of a Factor VIII (FVIII) inhibitor with a titer greater than orequal [>=] 0.4 Bethesda units (BU) (by Nijmegen assay) or >=0.6 BU (by Bethesdaassay).

• Documented history of a VWF: RCo half-life <6 hours.

• Known hypersensitivity to any of the components of the study drug, such as mouse orhamster proteins.

• Medical history of immunological disorders, excluding seasonal allergicrhinitis/conjunctivitis/asthma, food allergies, or animal allergies.

• Medical history of a thromboembolic event.

• Human immunodeficiency virus (HIV) positive, with an absolute CD4 count <200/ cubicmillimeter (mm^3).

• In the judgment of the Investigator, the participant has another clinicallysignificant concomitant disease (e.g. uncontrolled hypertension, cancer) that maypose additional risks for the participant.

• Diagnosis of significant liver disease, as evidenced by, but not limited to, any ofthe following: serum alanine aminotransferase (ALT) of 5 times the upper limit ofnormal; hypoalbuminemia; portal vein hypertension (e.g. presence of otherwiseunexplained splenomegaly, history of esophageal varices) or liver cirrhosisclassified as Child B or C.

• Diagnosis of renal disease, with a serum creatinine level >=2.5 milligram perdeciliter (mg/dL).

• Immunomodulatory drug treatment other than anti-retroviral chemotherapy (e.g. α-interferon, or corticosteroid agents at a dose equivalent to hydrocortisonegreater than 10 milligram per day [mg/day] (excluding topical treatment [e.g.ointments, nasal sprays]), within 30 days prior to signing the informed consent (orassent, if appropriate).

• If female, participant is pregnant or lactating at the time informed consent (orassent, if appropriate) is obtained.

• Participant has participated in another clinical study involving an investigationalproduct (IP), other than rVWF with or without ADVATE, or investigational devicewithin 30 days prior to enrollment or is scheduled to participate in anotherclinical study involving an IP other than rVWF or investigational device during thecourse of this study.

• Participant's legal representative is a family member or employee of theInvestigator.