Study of Brentuximab Vedotin (SGN-35) in Pediatric Participants With Relapsed or Refractory (r/r) Systemic Anaplastic Large-Cell Lymphoma or Hodgkin Lymphoma

Inclusion Criteria: * Male or female participants aged 2 to \<18 years (5 to \<18 years for Hodgkin lymphoma \[HL\]) * Diagnosis of systemic anaplastic large-cell lymphoma (sALCL), or HL for which standard, curative, life-prolonging, or palliative treatment does not exist or is no longer effective * Participants with sALCL must have documented anaplastic lymphoma kinase (ALK) status and must be beyond first remission or refractory to front-line chemotherapy * Participants diagnosed with any relapsed or refractory CD30+ hematologic malignancy (e.g., primary mediastinal B-cell lymphoma) may be included in phase 1 of the study * Participants with HL must be in their second of later relapse, have failed systemic chemotherapy either as induction therapy for advanced stage disease or salvage therapy, and were ineligible for, refused, or previously received a stem cell transplant * Performance score ≥ 60 from Lansky Play Performance Scale if ≤16 years * Negative pregnancy test * Fertile Participants must use 2 effective methods of contraception prior to and through 6 months after the last dose of the study drug Exclusion Criteria: * Current diagnosis of primary cutaneous ALCL (those with systemic ALCL are eligible) * Received an allogeneic stem cell transplant \<3 months prior to the first dose of study medication, or presence of polymerase chain reaction (PCR)-detectable cytomegalovirus (CMV) in any post-allogeneic transplant participant * Receiving immunosuppressive therapy * R…