Unleashed monocytic engagement in Sézary syndrome during the combination of anti-CCR4 antibody with type I interferon.

ABSTRACT: Sézary syndrome (SS) is an aggressive leukemic expansion of skin-derived malignant CD4+ T cells. Drug monotherapy often results in disease relapse because of the heterogenous nature of malignant CD4+ T cells, but how therapies can be optimally combined remains unclear because of limitations in understanding the disease pathogenesis. We identified immunologic transitions that interlink mycosis fungoides with SS using single-cell transcriptome analysis in parallel with high-throughput T-cell receptor sequencing. Nascent peripheral CD4+ T cells acquired a distinct profile of transcription factors and trafficking receptors that gave rise to antigenically mature Sézary cells. The emergence of malignant CD4+ T cells coincided with the accumulation of dysfunctional monocytes with impaired fragment crystallizable γ-dependent phagocytosis, decreased responsiveness to cytokine stimulation, and limited repertoire of intercellular interactions with Sézary cells. Type I interferon supplementation when combined with a monoclonal antibody targeting the chemokine receptor type 4 (CCR4), unleashed monocyte induced phagocytosis and eradication of Sézary cells in vitro. In turn, coadministration of interferon-α with the US Food and Drug Administration-approved anti-CCR4 antibody, mogamulizumab, in patients with SS induced marked depletion of peripheral malignant CD4+ T cells. Importantly, residual CD4+ T cells after Sézary cell ablation lacked any immunologic shifts. These findings collectively unveil an auxiliary role for augmenting monocytic activity during mogamulizumab therapy in the treatment of SS and underscore the importance of targeted combination therapy in this disease.

Staphylococcus aureus induces drug resistance in cancer T cells in Sézary syndrome.

ABSTRACT: Patients with Sézary syndrome (SS), a leukemic variant of cutaneous T-cell lymphoma (CTCL), are prone to Staphylococcus aureus infections and have a poor prognosis due to treatment resistance. Here, we report that S aureus and staphylococcal enterotoxins (SE) induce drug resistance in malignant T cells against therapeutics commonly used in CTCL. Supernatant from patient-derived, SE-producing S aureus and recombinant SE significantly inhibit cell death induced by histone deacetylase (HDAC) inhibitor romidepsin in primary malignant T cells from patients with SS. Bacterial killing by engineered, bacteriophage-derived, S aureus-specific endolysin (XZ.700) abrogates the effect of S aureus supernatant. Similarly, mutations in major histocompatibility complex (MHC) class II binding sites of SE type A (SEA) and anti-SEA antibody block induction of resistance. Importantly, SE also triggers resistance to other HDAC inhibitors (vorinostat and resminostat) and chemotherapeutic drugs (doxorubicin and etoposide). Multimodal single-cell sequencing indicates T-cell receptor (TCR), NF-κB, and JAK/STAT signaling pathways (previously associated with drug resistance) as putative mediators of SE-induced drug resistance. In support, inhibition of TCR-signaling and Protein kinase C (upstream of NF-κB) counteracts SE-induced rescue from drug-induced cell death. Inversely, SE cannot rescue from cell death induced by the proteasome/NF-κB inhibitor bortezomib. Inhibition of JAK/STAT only blocks rescue in patients whose malignant T-cell survival is dependent on SE-induced cytokines, suggesting 2 distinct ways SE can induce drug resistance. In conclusion, we show that S aureus enterotoxins induce drug resistance in primary malignant T cells. These findings suggest that S aureus enterotoxins cause clinical treatment resistance in patients with SS, and antibacterial measures may improve the outcome of cancer-directed therapy in patients harboring S aureus.

Changes to Registered and Pivotal Clinical Trials after the 2011 Tri-Societies Guidelines for Clinical Endpoints and Response Criteria in Mycosis Fungoides and Sézary Syndrome.

Guidelines for mycosis fungoides and Sézary syndrome clinical trials were published in 2011 to standardize endpoint criteria and trial design. Our retrospective cohort study of mycosis fungoides/Sézary syndrome clinical trials registered on ClinicalTrials.gov and pivotal trials supporting drug approvals and label extensions evaluates adherence to these guidelines. Sixty-three trials met our inclusion criteria. In a subpopulation of trials, mean adherence to the guidelines was approximately 60%. When comparing trials that began in the first 6 years after their publication with those that started after, we found no difference in mean adherence (4.12 vs 3.41) (P = .15). Among the 8 pivotal trials supporting new mycosis fungoides or Sézary syndrome systemic therapies from 1990 to 2020, systemic trials published after 2011 were more likely to randomize patients (100 vs 0%, P = .036), perform superiority testing (100 vs 0%, P = .036), and use an intention-to-treat analysis (100 vs 0%, P = .036). The design of trials registered on Clinicaltrials.gov did not change significantly between the first 6 years after the publication of the guidelines and after. This demonstrates that the guidelines are still not consistently implemented across all trials. However, registrational trials were more likely to implement the recommendations.

Advancements in the treatment of mycosis fungoides and Sézary syndrome: monoclonal antibodies, immunotherapies, and Janus kinase inhibitors.

Mycosis fungoides (MF) and Sézary syndrome (SS) are forms of cutaneous T cell lymphoma (CTCL) that pose significant challenges in their clinical management, particularly in refractory and advanced-stage disease. With the emergence of novel therapeutic modalities however, there are increasing opportunities to exploit the current understanding of pathophysiologic mechanisms of MF/SS for treatment. This review summarizes recent advances in the treatment of MF/SS, with a focus on monoclonal antibodies, immunotherapies, and Janus kinase (JAK) inhibitors, including ongoing clinical trials.

Advances in the treatment of mycoses fungoides and Sézary syndrome: a narrative update in skin-directed therapies and immune-based treatments.

Mycoses fungoides (MF) and Sézary syndrome (SS) are cutaneous T-cell lymphomas that are often challenging to manage given the absence of reliably curative therapies, at times high symptom burden with significant detriment to quality of life, and need for ongoing treatment for disease and symptom control. Recent developments in skin-directed treatments include optimizing the use of existing topical therapies, the introduction of known dermatological agents and treatment modalities for the specific treatment of MF/SS (such as mechlorethamine gel, calcineurin inhibitor creams, and photodynamic therapy), and novel local and topical agents. For advanced disease, dedicated clinical trials have translated to exciting progress, leading to the approval of brentuximab vedotin (2017) and mogamulizumab (2018) for relapsed MF/SS. Additional studies of other active systemic agents, including various cellular therapies, represent further attempts to add to the therapeutic armamentarium in treating MF/SS. In this review, we highlight these recent advancements, ranging from optimization of skin-directed therapies to the introduction of novel systemic agents. We focus on therapies approved in the preceding five years or under investigation in advanced-phase clinical trials.

International study of treatment efficacy in SS shows superiority of combination therapy and heterogeneity of treatment strategies.

Despite increasing availability of therapies, patients with Sezary syndrome (SS) commonly endure multi-line treatment journeys, mostly with partial responses of short duration. Measuring clinical benefit is challenging; time-to-next-treatment (TTNT) provides a robust, objective measurement of efficacy. This international observational study examines patterns of clinical care and therapeutic benefit as measured by TTNT. TTNT was calculated for monotherapies and combination therapies, with consideration to treatment line. 178 patients with SS (73% de novo, 27% secondary) were included, receiving 721 lines of systemic therapy, with median follow-up of 56.9 months. Across all lines, 58 different therapeutic regimens were prescribed (54 were systemic therapies) and classified into 17 treatment groups. The most common first-line treatments were extracorporeal photopheresis (ECP)-containing combination therapy (20%) and retinoid monotherapy (19%). Median TTNT for all first-line therapies was short (5.4 months). First-line, combination therapies had longer median TTNT than monotherapies, 10.0 vs 5.0 months (P = .004), respectively. Later delivery of combination therapies was associated with shorter clinical benefit, with median TTNT reduced to 6.2 and 2.2 months for mid-line (2nd-4th line) and late-line (≥5th line), respectively (P < .001). First-line ECP-containing treatments were associated with longer median TTNT than non-ECP-containing treatments, 9.0 vs 4.9 months (P = .007). For both ECP-monotherapy and ECP-containing combination therapy, significant reductions in TTNT were seen in later lines. These data suggest therapeutic benefit from first-line delivery of combination therapy for SS and favor early inclusion of ECP in the treatment algorithm for those who can access it.

Overall survival in the UK in mycosis fungoides or Sézary syndrome cutaneous T-cell lymphoma: comparative effectiveness of mogamulizumab versus current standard of care.

Aim: Due to extensive treatment switching in the MAVORIC trial, lack of UK regulatory licence for the comparator, overall survival (OS) with mogamulizumab was compared with patients with previously treated advanced mycosis fungoides/Sézary syndrome (MF/SS) in real-world setting. Design, setting & participants: Data were from the Hospital Episode Statistics database (all patients in NHS secondary care system in 2009-2019). Patients were selected according to trial inclusion criteria, then trial and HES samples were matched on selected variables with significant imbalance. Outcomes: The analysis indicated significant improvement in OS for mogamulizumab treatment compared with UK clinical practice (hazard ratio: 0.36, 95% CI: 0.24, 0.53). Conclusion: Results suggest an OS advantage for patients with advanced MF/SS treated with mogamulizumab in MAVORIC trial compared with UK clinical practice.

Cost-utility analysis of mogamulizumab in advanced mycosis fungoides and Sézary syndrome cutaneous T-cell lymphoma.

Aim: This study assessed the cost-utility of mogamulizumab, a novel monoclonal antibody, versus established clinical management (ECM) in UK patients in previously treated advanced mycosis fungoides (MF)/Sézary syndrome (SS). Materials & methods: Lifetime partitioned survival model based on overall survival, next treatment-free survival and the use of allogeneic stem cell transplant was developed. Inputs were from the pivotal MAVORIC trial, real-world evidence and published literature. Extensive sensitivity analyses were conducted. Results: Discounted incremental quality-adjusted life years (QALYs), costs and incremental cost-effectiveness ratio were 3.08, £86,998 and £28,233. Results were most sensitive to the survival extrapolations, utilities and costs after loss of disease control. Conclusion: Mogamulizumab is a cost-effective alternative to ECM in UK patients with previously treated advanced MF/SS.

CCR4-IL2 bispecific immunotoxin is more effective than brentuximab for targeted therapy of cutaneous T-cell lymphoma in a mouse CTCL model.

Cutaneous T-cell lymphoma (CTCL) encompasses two main subtypes: mycosis fungoides and Sezary syndrome. Global response rates for the systemic treatment of mycosis fungoides and Sezary syndrome are approximately 30%, and none of these treatments are thought to be curative. C-C chemokine receptor type 4 (CCR4) and CD25 are encouraging targets for the treatment of CTCL and are individually targeted by mogamulizumab and denileukin diftitox, respectively. We developed a novel CCR4-IL2 bispecific immunotoxin (CCR4-IL2 IT) targeting both CCR4 and CD25. CCR4-IL2 IT demonstrated superior efficacy against CCR4+ CD25+ CD30+ CTCL in an immunodeficient NSG mouse tumor model. Investigative New Drug-enabling studies of CCR4-IL2 IT are ongoing, including Good Manufacturing Practice production and toxicology studies. In this study, we compared the in vivo efficacy of CCR4-IL2 IT versus the US Food and Drug Administration-approved drug, brentuximab, using an immunodeficient mouse CTCL model. We demonstrated that CCR4-IL2 IT was significantly more effective in prolonging survival than brentuximab, and combination treatment of CCR4-IL2 IT and brentuximab was more effective than brentuximab or CCR4-IL2 IT alone in an immunodeficient NSG mouse CTCL model. Thus, CCR4-IL2 IT is a promising novel therapeutic drug candidate for CTCL treatment.

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

BACKGROUND: Efficacy 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): Sézary syndrome (SS) or Mycosis Fungoides (MF). OBJECTIVES: The 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). METHODS: In 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. RESULTS: The 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. CONCLUSIONS: This large French study confirmed the effectiveness and tolerability of mogamulizumab in SS and MF patients in routine medical practice.

Complete Response to tenalisib and romidepsin with long-term maintenance using tenalisib monotherapy in a patient with relapsed and refractory sézary syndrome.

Mycosis fungoides (MF) and Sézary Syndrome (SS) are the most common subtypes of cutaneous T cell lymphomas (CTCL). Advanced-stage MF/SS have poor prognoses and may be refractory to multiple systemic treatments. These cases can be difficult to achieve and maintain complete response and there is a need for novel therapeutics. Inhibition of the phosphatidylinositol 3-kinase (PI3K) pathway by Tenalisib presents one such emerging drug. We report a relapsed/refractory SS patient achieving complete remission using the combination of Tenalisib and Romidepsin and subsequently maintaining long-duration CR with Tenalisib monotherapy.

Integrating novel agents into the treatment of advanced mycosis fungoides and Sézary syndrome.

Agents targeting the unique biology of mycosis fungoides and Sézary syndrome are quickly being incorporated into clinical management. With these new therapies, we are now capable of inducing more durable responses and even complete remissions in advanced disease, outcomes which were exceedingly rare with prior therapies. Yet, even this new generation of therapies typically produce objective responses in only a minority of patients. As our therapeutic options increase, we are now challenged with selecting treatments from a growing list of options. To gain the full benefit of these novel agents, we must develop strategies to match treatments for the patients most likely to benefit from them. Here, we consider both the current approaches to treatment selection based on clinical features and the future of molecular biomarker-guided therapy for patients with this heterogeneous disease.

Impact of blood involvement on efficacy and time to response with mogamulizumab in mycosis fungoides and Sézary syndrome.

BACKGROUND: Cutaneous T-cell lymphomas (CTCL) are rare types of non-Hodgkin lymphoma, which present in skin. Mycosis fungoides (MF) and Sézary syndrome (SS) are subtypes which make up two-thirds of all CTCL cases. The phase 3 MAVORIC study (NCT01728805) compared mogamulizumab to vorinostat in MF and SS patients, with post hoc data showing a trend for higher efficacy in mogamulizumab-treated patients as baseline blood tumour burden increases. OBJECTIVES: The aim of this study was to use updated post hoc analyses in order to examine the efficacy of mogamulizumab and vorinostat in MF patients when stratified by baseline blood involvement and to determine what factors affect time-to-global and time-to-skin response to inform clinical follow-up. METHODS: Post hoc analyses were carried out using data from MAVORIC. Overall response rate (ORR), progression-free survival (PFS) and time-to-next-treatment (TTNT) data were used to assess efficacy in patients with MF. Time-to-global response (TTR) was examined by disease subtype, by blood involvement in MF patients, and time-to-skin response was examined by blood involvement in MF patients. RESULTS: Numerically superior results were seen for ORR, PFS and TTNT in mogamulizumab-treated patients with MF compared with vorinostat, with a trend for outcomes improving with increasing baseline blood class. Statistically significant results for mogamulizumab compared with vorinostat were seen for MF B1 pts for PFS (8.43 vs. 2.83 months, p = 0.003) and TTNT (11.9 vs. 3.13 months, p = 0.002), and for MF B2 pts for ORR (46.2 vs. 9.1 months, p = 0.033). CONCLUSIONS: In mogamulizumab-treated MF patients, ORR and PFS were seen to improve with increasing blood involvement, which led to improved TTNT. TTR was more predictable for mogamulizumab-treated MF patients with blood involvement, and skin response may take longer than previously reported in some patients.