Mogamulizumab Is Efficacious in Sezary Syndrome and Mycosis Fungoides

Mogamulizumab is effective and tolerable in patients with Sezary syndrome (SS) or mycosis fungoides (MF), according to study results published in Journal of the European Academy of Dermatology and Venereology.

Researchers conducted a noninterventional, retrospective study at 14 centers in France among adult patients who received mogamulizumab at least once for MF or SS until March 2020. Retrospective data were obtained regarding patient characteristics, type of cutaneous T-cell lymphoma, disease history, previous therapies used for MF or SS, disease stage at diagnosis and mogamulizumab initiation, and adverse events, as well as other attributes.

Overall response rate (ORR) was the primary criterion and was defined as the proportion of patients with complete response or partial response with mogamulizumab.

The overall analysis population included 122 participants with a clear diagnosis — 53 with MF and 69 with SS. Of this group, 109 participants (50 with MF and 59 with SS) were included in the effectiveness population. They were a mean (SD) age of 66.6 (12.1) years, with an equal man to woman ratio, and their median disease duration was 2.5 years (IQR, 1.3-5.6) before mogamulizumab initiation.

Among the 109 participants in the effectiveness population, the median follow-up and mogamulizumab treatment duration was 8.7 months (IQR, 4.0-15.0; range, 0.6-72.6) and 4.9 months (IQR, 2.2-7.4; range, 0.5-71.6), respectively. The ORR for mogamulizumab therapy was 58.7% (95% CI, 48.9-68.1). The participants with SS had a higher response rate compared with those with MF (69.5%; 95% CI, 56.1-80.8; and 46.0%; 95% CI, 31.8-60.7, respectively).

Complete response was achieved by 10 of 59 participants with SS (16.9%; 95% CI, 8.4-29.0) and by 4 of 50 participants with MF (8.0%; 95% CI, 2.2-19.2). Partial response was achieved by 31 of 59 participants with SS (52.5%; 95% CI, 39.1-65.7) and by 19 of 50 participants with MF (38.0%; 95% CI, 24.7-52.8).

Blood response was achieved in 45 of 55 (81.8%) participants with SS. Skin overall response was achieved by 38 of 61 (66.7%) participants with SS and 23 of 50 participants with MF (46.0%). The ORR was significantly increased (P =.0030) in participants with blood involvement (69.5% for B2 in those with SS and 75.0% for B1 in those with MF), compared with 36.8% for B0 in participants with MF.

The median progression-free survival (PFS) in the overall analysis population was an estimated 15.0 months (95% CI, 9.0-50.8), with no significant difference between the groups (P =.0542). At 12 months, the estimated PFS rate was 56.3% (95% CI, 44.9-66.3) in the overall analysis population. The median overall survival was not reached.

At least 1 treatment-emergent adverse drug reaction (ADR) occurred in 70 of 124 participants in the safety population (56.5%), with a total of 203 ADRs reported. Lymphopenia was the most frequently occurring event (23.4%). Serious ADRs occurred in 23 participants (18.5%), primarily rash (8.1%) and vitiligo (2.4%). In the 15 participants (12.1%) who had ADRs that led to permanent discontinuation of mogamulizumab, rash (7.3%) was the most reported event.

Limitations of the study include the noninterventional and retrospective design, and the follow-up duration that ranged from 0.5 to 72.6 months, which led to the heterogeneous effectiveness population.

“Our real-life data from a large French population of patients with SS or FS, less selective than in clinical trials, were consistent with previous findings and confirmed the effectiveness of mogamulizumab (high level and rapid onset of treatment response, in particular in patients with blood involvement), as well as its manageable safety profile,” conclude the researchers.

Disclosure: This work was supported by Kyowa Kirin Pharma. Some of the study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of disclosures.

This article originally appeared on Dermatology Advisor