|Inclusion Criteria:||1) Patients who met all inclusion/exclusion criteria for and participated in the SGN35-005 clinical study, were treated with placebo in the SGN35-005 clinical study after autologous SCT, and experienced progression of HL based on the Revised Response Criteria for Malignant Lymphoma as defined by protocol in study SGN35-005. OR In the United States (US) only, patients with relapsed or refractory HL OR In the United States (US) only, patients with relapsed or refractory systemic ALCL who have previously received frontline chemotherapy (cytoxan, hydroxydoxorubicin, oncovin, and prednisone CHOP or multi-agent chemotherapy regimens with curative intent) and documented anaplastic lymphoma kinase (ALK) status.|
2) Patients who were treated with placebo in the SGN35-005 clinical study after autologous stem cell transplant (ASCT) and experienced progression of HL based on the Revised Response Criteria for Malignant Lymphoma (Cheson 2007) as defined by protocol in study SGN35-005.
3) Age greater than or equal to 18 years. Patients of age greater than or equal to 6 years may be enrolled at US sites. Permission from the Sponsor must be granted prior to enrollment for ages 6 years to <12 years.
4) An Eastern Cooperative Oncology Group (ECOG) performance status of </= 2.
5) Patients must have completed any previous treatment with radiation, chemotherapy, biologics and/or investigational agents at least 4 weeks prior to the first dose of SGN-35, unless underlying disease is progressing on therapy.
6) Females of childbearing potential must have a negative serum or urine Beta-hCG pregnancy test result within 7 days prior to the first dose of brentuximab vedotin. Females of non-childbearing potential are those who are postmenopausal for more than 1 year or who have had a bilateral tubal ligation or hysterectomy.
7) Both females of childbearing potential and males who have partners of childbearing potential must agree to use an effective contraceptive method during the study and for 30 days following the last dose of study drug.
8) The following baseline laboratory values are required: absolute neutrophil count (ANC) >/= 1000/microL, platelets >/= 50,000/microL, total bilirubin </= 1.5 x upper limit of normal (ULN) or </= 3 x ULN for patients with Gilbert's disease, serum creatinine </= 1.5 x ULN, alanine aminotransferase (ALT) and aspartate aminotransferase (AST) </= 2.5 x ULN.
9) Patients or their legally authorized representative must provide written informed consent.