Clinical spectrum, outcome and management of immune thrombocytopenia associated with myelodysplastic syndromes and chronic myelomonocytic leukemia.

Myelodysplastic syndromes (MDS) and chronic myelomonocytic leukemia (CMML) are associated with systemic inflammatory or autoimmune diseases in 10-20 % of cases. Among them, immune thrombocytopenia (ITP) has been reported but large studies assessing this association are missing. Whether such patients have a particular phenotype and require particular management is unclear. This study analyzes the clinical spectrum, outcome and therapeutic management of patients with ITP associated with MDS or CMML, in comparison (i) to patients with primary ITP without MDS/CMML and (ii) to patients with MDS/CMML without ITP. Forty-one MDS/CMML-associated ITP patients were included, with chronic ITP in 26 (63%) patients, low-risk myelodysplasia in 30 (73%) patients and CMML in 24 (59%) patients. An associated autoimmune disease was noted in 10 (24%) patients. In comparison to primary ITP patients, MDS/CMML-associated ITP patients had a higher occurrence of severe bleeding despite similar platelet counts at diagnosis. First-line treatment consisted of glucocorticoids (98%) and intravenous immunoglobulin (IVIg) (56%). Response achievement with IVIg was more frequent in primary ITP than in MDS/CMML-associated ITP patients. Response rates to second-line therapies were not statistically different between primary ITP and MDS/CMMLassociated ITP patients. Ten percent (n=4) of patients with MDS/CMML-associated ITP had multirefractory ITP versus none in primary ITP controls. After a median follow-up of 60 months, there was no difference in overall survival between MDS/CMML-associated ITP and primary ITP patients. Leukemia-free-survival was significantly better in MDS/CMMLassociated ITP patients than in MDS/CMML without ITP MDS/CMML-associated ITP have a particular outcome with more severe bleeding and multirefractory profile than primary ITP, similar response profile to primary ITP therapy except for IVIg, and less progression toward acute myeloid leukemia than MDS/CMML without ITP.

ICOS is widely expressed in cutaneous T-cell lymphoma, and its targeting promotes potent killing of malignant cells.

The treatment of advanced-stage cutaneous T-cell lymphoma (CTCL) remains an unmet medical need. Mogamulizumab, anti-KIR3DL2, and brentuximab vedotin (BV), an anti-CD30 antibody-drug conjugate (ADC) coupled with monomethyl-auristatin-E (MMAE), provided encouraging results, but new targeted therapies are needed. Inducible T-cell costimulator (ICOS), a T-cell costimulatory receptor, is a promising therapeutic target, not only because it is expressed by malignant T cells in CTCL but also because of its connection with the suppressive activity of regulatory T (Treg) cells. Immunohistochemical analysis revealed that ICOS was widely expressed by malignant cells in skin biopsy specimens from 52 patients with mycosis fungoides and Sézary syndrome (SS), as well as in involved node biopsy specimens from patients with SS. Furthermore, flow cytometry demonstrated its strong expression by circulating tumor cells in all our patients with SS. Percentages of ICOS+ Treg cells were significantly higher in patients with SS than in healthy donors. We then investigated the preclinical efficacy of anti-ICOS ADCs generated by coupling murine anti-ICOS monoclonal antibodies with MMAE and pyrrolobenzodiazepine. In 3 CTCL cell lines (Myla, MJ, and HUT78), we observed a significant dose-dependent decrease in cell viability in the presence of anti-ICOS ADCs. In addition, anti-ICOS-MMAE ADCs had an in vitro and in vivo efficacy superior to BV in a mouse xenograft model (MyLa). Finally, we assessed the efficacy of anti-ICOS ADCs in ICOS+ patient-derived xenografts from patients with SS and angioimmunoblastic T-cell lymphoma. Collectively, our findings provide the preliminary basis for a therapeutic trial.

Biologics in myelodysplastic syndrome-related systemic inflammatory and autoimmune diseases: French multicenter retrospective study of 29 patients.

BACKGROUND: Systemic inflammatory and autoimmune diseases (SIADs) associated with myelodysplastic syndromes are often difficult to treat. Corticosteroids are efficient but only usually at high doses. The use of biologics needs to be specified. METHODS: In a French multicenter retrospective study, we analyzed the efficacy and safety of biologics (tumor necrosis factor-α [TNF-α] antagonists, tocilizumab, rituximab and anakinra) for SIADs associated with myelodysplastic syndromes (MDSs). Clinical, biological and overall treatment responses were evaluated. When several lines of treatment were used, data were analyzed before and at the end of each treatment line and were pooled to compare overall response among steroids, disease-modifying anti-rheumatic drugs (DMARDs) and biologics. RESULTS: We included 29 patients (median age 67years [interquartile range 62-76], 83% males) with MDS-related SIADs treated with at least one biologic. The MDSs were predominantly refractory anemia with excess blasts 1 (38%) and refractory cytopenia with multilineage dysplasia (21%). The SIADs were mainly arthritis (n=6; 20%), relapsing polychondritis (n=8; 30%) and vasculitis (n=10; 34%). During a 3-year median follow-up (IQR 1.3-4.5), a total of 114 lines of treatments were used for all patients: steroids alone (22%), DMARDs (23%), TNF-α antagonists (14%), anakinra (10%), rituximab (10%), tocilizumab (7%) and azacytidine (9%). Considering all 114 lines, overall response (complete and partial) was shown in 54% cases. Overall response was more frequent with steroids (78%) and rituximab (66%) than DMARDs (45%) and other biologics (33%) (p<0.05). Rituximab had better response in vasculitis and TNF-α antagonists in arthritis. During follow-up, 20 patients (71%) presented at least one severe infection. CONCLUSION: This nationwide study demonstrates the efficacy of steroids for SIAD-associated MDSs but a high frequency of steroid dependence. The response to biologics seems low, but rituximab and azacytidine seem promising.