A Safety Study of SGN-35C in Adults With Advanced Cancers

Open to people ages 18 years and up

• Tumor type
• For dose escalation and dose optimization (Parts A and B):
  • Participants with a histologically confirmed lymphoid neoplasm who in the judgement of the investigator have no appropriate standard therapy available at the time of enrollment and are a candidate for SGN- 35C treatment. Eligible subtypes and treatment status are as follows:
    • Participants with relapsed/refractory (R/R) cHL: should have received at least 3 prior systemic therapies including autologous stem cell transplant [ASCT] (ASCT and the associated high-dose chemotherapy prior to ASCT are considered to be 1 prior line) or an anti-PD-1 agent (or refused/were ineligible); or 2 prior systemic therapies if, according to the investigator, no other appropriate standard treatment is available.
    • Participants with R/R PTCL (excluding systematic anaplastic large cell lymphoma [sALCL]): should have received at least 2 prior systemic therapies, or 1 prior systemic therapy if, according to the investigator, no other appropriate standard treatment is available.
    • Participants with R/R sALCL: should have received at least 2 prior systemic therapies, including 1 brentuximab vedotin-containing regimen, or 1 prior line of systemic therapy including brentuximab vedotin, cyclophosphamide, doxorubicin, and prednisone.
    • Participants with R/R DLBCL: should have received at least 2 prior systemic therapies, including ASCT and chimeric antigen receptor (CAR) T-cell therapy, or were ineligible, or refused.
  • Participants with PTCL and DLBCL must have a detectable cluster of differentiation 30 (CD30) expression level (≥1%) in tumor tissue from the most recent biopsy obtained at or after relapse by local testing.
• For dose expansion (Part C):
  • Participants are eligible irrespective of CD30 expression on tumor tissue; however, participants must provide tumor tissue for evaluation of CD30 expression from the most recent biopsy obtained at or after relapse.
  • Participants with cHL, PTCL, sALCL, and DLBCL: Eligible subtypes are the same as defined in Parts A and B
  • If activated, the biology cohort may enroll the populations included in Parts A, B, and C.
• Eastern Cooperative Oncology Group (ECOG) Performance Status score of ≤1
• Fluorodeoxyglucose positron emission tomography (FDG-PET) avid and bidimensional measurable disease as documented by radiographic technique (spiral computed tomography [CT] preferred)

• Previous exposure to any antibody-drug conjugates (ADCs) with camptothecin-based payload.
• History of another malignancy within 3 years before the first dose of study drug, or any evidence of residual disease from a previously diagnosed malignancy. Exceptions are malignancies with a negligible risk of metastasis or death
• Active cerebral/meningeal disease related to the underlying malignancy
• Received previous ASCT infusion <12 weeks prior to the first dose of SGN-35C.
• Previous allogeneic stem cell transplant (SCT) if they meet any of the following criteria:
  • <100 days from allogeneic SCT. Participants ≥100 days from allogeneic SCT who are stable without immunosuppressive therapy for at least 12 weeks are permitted.
  • Active acute or chronic graft-versus-host disease (GVHD) or receiving immunosuppressive therapy as treatment for or prophylaxis against GVHD.
• History of clinically significant GI bleeding, intestinal obstruction, or GI perforation within 6 months of initiation of trial treatment.