Introduction: The prognosis for patients (pts) with advanced-stage Mycosis Fungoides (MF) and Sézary syndrome (SS) is poor and better treatments are needed.
Methods: This is a phase 1, 3+3 dose de-escalation study of brentuximab vedotin (BV) and mogamulizumab (Moga) in relapsed/refractory (R/R) MF or SS (NCT05414500). Moga is administered at 1 mg/kg weekly x 5 weeks then every other week for 12 cycles. BV is administered every 28 days for 12 cycles. The starting dose of BV is 1.8 mg/kg and will be de-escalated to 1.2 mg/kg or 1.0 mg/kg if needed. This study is enrolling 9-18 pts with R/R MF/SS with CD30 positivity >1% without prior Moga exposure. Pts with BV exposure > 6 months prior to study start are allowed.
Primary objective: To determine safety, tolerability and recommended doses of BV and Moga given in combination for pts with R/R MF and SS.
Results and Conclusions: Four pts have been enrolled. Disease stage was IIA (1 pt), IIB (2 pts) and IIIB (1 pt); 3 of 4 have large cell transformation. All pts have completed the dose-limiting toxicity (DLT) evaluation period without DLTs. All adverse events were grade 1-2. Adverse events of special interest were infusion reactions (grade 2 in 1 pt), neuropathy (grade 1 in 1 pt and grade 2 in 1 pt) and rash (grade 2 in 2 pts). The most common adverse events were diarrhea, myalgia, neuropathy, and rash (all in 2/4 pts). Best global responses were partial response (2 pts) and stable disease (1 pt). Enrollment is ongoing and additional data will be presented.
Acknowledgements: Support provided by Pfizer and Kyowa Kirin, Inc.
