Background: Cutaneous T-cell lymphoma (CTCL) are a heterogeneous group of lymphoproliferative disorders characterized by malignant atypical clonal T lymphocytes with skin involvement, most commonly including mycosis fungoides (MF) and Sezary Syndrome (SS). MF and SS are difficult to treat once they become resistant to initial systemic therapy. In this study we examine the efficacy and safety of mogamulizumab retreatment after prior discontinuation.
Methods: Five treatment sites, including our institution, identified 12 patients with MF (n=4) or SS (n=8) who met inclusion criteria. Patients had to be treated with mogamulizumab, discontinued from the agent, and then retreated with the same agent. Response was assessed on flow cytometry (n=11) and on clinical exam (n=1).
Results: On initial treatment with mogamulizumab objective response rate (ORR) was 66.7% and mogamulizumab was discontinued after a median of 7 months of treatment. Patients received a median of 1 alternative MF/SS therapy prior to retreatment with mogamulizumab over a median of 4 months before the agent was resumed. Retreatment responses include CR (n=2, 16.7%), PR (n=4, 33.3%), PD (n=2, 16.7%), and unknown (n=4, 33.3%). ORR with mogamulizumab retreatment was 50% and 50% of participants received concurrent treatment with another agent including interferon, extracorporeal photophoresis, or steroids (1 oral and 1 topical). Reason for treatment discontinuation upon retreatment include adverse event (n=2, 23%), disease progression (n=3, 23%), complete response (n=2, 15%), lost to follow-up (n=1, 8%). Both patients with CR received monotherapy with mogamulizumab on retreatment.
Conclusions: Mogamulizumab is an effective agent for patients with MF/SS, especially those with blood involvement. This study shows that retreatment with mogamulizumab after a prior discontinuation is a safe and effective therapeutic option for CTCL patients.
