BREntuximab Vedotin in SEcond LIne Therapy BEfore Transplant

This study tests brentuximab vedotin (an antibody-drug combination that targets a protein called CD30 on cancer cells) as second-line therapy for people with Hodgkin's lymphoma that has come back after initial treatment, before they receive a stem cell transplant. The goal is to see whether brentuximab can help more patients respond well enough to proceed to transplant. **You may be eligible if...** - You are between 18 and 65 years old - You have been confirmed to have classical Hodgkin's lymphoma with CD30 positive disease - Your disease has relapsed or is refractory to first-line treatment - You have measurable disease (at least one lymph node or mass 1.5 cm or larger) - You have no significant nerve damage (neuropathy less than grade 2) **You may NOT be eligible if...** - You have lymphocyte-predominant nodular Hodgkin's lymphoma (a different subtype) - You have previously received brentuximab vedotin - You are pregnant or breastfeeding - You have HIV, active hepatitis B or C - You have significant heart problems or serious nerve disease - You have had another cancer within the past 3 years - You have significant peripheral neuropathy (nerve pain or weakness) Talk to your doctor to see if this trial is right for you.