Effectiveness of mogamulizumab in patients with Mycosis Fungoides or Sezary syndrome: A multicentre, retrospective, real-world French study

BackgroundEfficacy and safety of mogamulizumab, a monoclonal antibody directed against C-C chemokine receptor 4, were demonstrated in a previous multinational clinical trial conducted in patients with previously treated cutaneous T-cell lymphoma (CTCL): Sezary syndrome (SS) or Mycosis Fungoides (MF). ObjectivesThe real-world French OMEGA study aimed to describe effectiveness and tolerability of mogamulizumab in adult patients with CTCL, overall and according to the disease (SS or MF). MethodsIn this retrospective study, patients treated with mogamulizumab for SS or MF were included from 14 French expert centres. The overall response rate (ORR) under treatment was described (primary criterion), as well as treatment use and safety data. ResultsThe 122 analysed patients (69 SS, 53 MF) were aged 66.6 +/- 12.1 years at mogamulizumab initiation, and their median disease duration was 2.5 years (IQR: 1.3-5.6). Prior to treatment start, they received a median of three systemic CTCL therapies (2-5). Overall, 77.8% of patients suffered from advanced disease (Stage IIB-IVB), with frequent blood (B1/B2) involvement (67.5%). Over the treatment period (median: 4.6 months, 2.1-7.2), 96.7% of patients received all the planned mogamulizumab infusions. Among the 109 patients evaluable for effectiveness, ORR was 58.7% (95% CI [48.9-68.1]) overall, 69.5% [56.1-80.8] in SS and 46.0% [31.8-60.7] in MF. Compartmental response in the blood was observed in 81.8% [69.1-90.9] of SS patients. Skin responses were observed in 57.0% [47.0-66.5] of patients overall, 66.7% [52.9-78.6] in SS and 46.0% [31.8-60.7] in MF. The most common serious adverse drug reactions were rash (8.1% of patients) and infusion-related reactions (2.4%) which led to treatment discontinuation in 7.3% and 0.8% of patients, respectively. One patient with SS died from mogamulizumab-related tumour lysis syndrome. ConclusionsThis large French study confirmed the effectiveness and tolerability of mogamulizumab in SS and MF patients in routine medical practice.