Impaired FADD/BID signaling mediates cross-resistance to immunotherapy in Multiple Myeloma.

The treatment landscape in multiple myeloma (MM) is shifting from genotoxic drugs to immunotherapies. Monoclonal antibodies, immunoconjugates, T-cell engaging antibodies and CART cells have been incorporated into routine treatment algorithms, resulting in improved response rates. Nevertheless, patients continue to relapse and the underlying mechanisms of resistance remain poorly understood. While Impaired death receptor signaling has been reported to mediate resistance to CART in acute lymphoblastic leukemia, this mechanism yet remains to be elucidated in context of novel immunotherapies for MM. Here, we describe impaired death receptor signaling as a novel mechanism of resistance to T-cell mediated immunotherapies in MM. This resistance seems exclusive to novel immunotherapies while sensitivity to conventional anti-tumor therapies being preserved in vitro. As a proof of concept, we present a confirmatory clinical case indicating that the FADD/BID axis is required for meaningful responses to novel immunotherapies thus we report impaired death receptor signaling as a novel resistance mechanism to T-cell mediated immunotherapy in MM.

Efficacy and safety in patients with haemophilia A switching to octocog alfa (BAY 81-8973): Final results of the global real-world study, TAURUS.

OBJECTIVES: To report the final results of the 2-year TAURUS study, assessing weekly prophylaxis dosing regimens of octocog alfa (Kovaltry®/BAY 81-8973) used in standard clinical practice in patients with moderate-to-severe haemophilia A. METHODS: TAURUS (NCT02830477) is a phase 4, multinational, prospective, non-interventional, single-arm study in patients of any age with moderate or severe haemophilia A (≤5% factor [F]VIII activity). TAURUS was designed to primarily investigate weekly prophylaxis dosing regimens used in standard clinical practice. Annualised bleeding rates (ABRs), treatment satisfaction and adherence, and safety were also assessed. RESULTS: Of 302 patients included in the full analysis set, 84.4% (n = 255) maintained their octocog alfa prophylaxis baseline regimen throughout the study, with a majority of patients (76.5%, n = 231) on two times or three times weekly regimens at the end of the observation period (≥1-≤2 years). ABRs, treatment satisfaction, and adherence remained stable during the observation period. Octocog alfa was well tolerated and there were no new or unexpected adverse events. CONCLUSIONS: These data show that a smooth transition is observed when switching to octocog alfa from a previous FVIII treatment, with no safety issues and stable bleeding rates in a real-world setting of patients with moderate-to-severe haemophilia A.

CyTOF analysis identifies unusual immune cells in urine of BCG-treated bladder cancer patients.

High grade non-muscle-invasive bladder tumours are treated with transurethral resection followed by recurrent intravesical instillations of Bacillus Calmette Guérin (BCG). Although most bladder cancer patients respond well to BCG, there is no clinical parameter predictive of treatment response, and when treatment fails, the prognosis is very poor. Further, a high percentage of NMIBC patients treated with BCG suffer unwanted effects that force them to stop treatment. Thus, early identification of patients in which BCG treatment will fail is really important. Here, to identify early stage non-invasive biomarkers of non-responder patients and patients at risk of abandoning the treatment, we longitudinally analysed the phenotype of cells released into the urine of bladder cancer patients 3-7 days after BCG instillations. Mass cytometry (CyTOF) analyses revealed a large proportion of granulocytes and monocytes, mostly expressing activation markers. A novel population of CD15+CD66b+CD14+CD16+ cells was highly abundant in several samples; expression of these markers was confirmed using flow cytometry and qPCR. A stronger inflammatory response was associated with increased cell numbers in the urine; this was not due to hematuria because the cell proportions were distinct from those in the blood. This pilot study represents the first CyTOF analysis of cells recruited to urine during BCG treatment, allowing identification of informative markers associated with treatment response for sub-selection of markers to confirm using conventional techniques. Further studies should jointly evaluate cells and soluble factors in urine in larger cohorts of patients to characterise the arms of the immune response activated in responders and to identify patients at risk of complications from BCG treatment.

Therapeutic potential of an anti-CCR9 mAb evidenced in xenografts of human CCR9+ tumors.

Relapsed or refractory T acute lymphoblastic leukemia (T-ALL) still carries poor prognosis. Aiming to improve outcomes, the therapeutic potential of an anti-CCR9 monoclonal antibody (mAb 92R), targeting the human chemokine-receptor CCR9 is analyzed on orthotopic xenotransplants. 92R mAb treatment of mice carrying human CCR9+ T-ALL cell lines or primary T cell leukemias inhibits tumor growth and increases survival. The therapeutic effects of 92R are specific and synergize with chemotherapeutic agents increasing survival. Furthermore, 92R decreases size of non-hematopoietic tumors with a forced CCR9 expression and of solid tumors generated by the pancreatic adenocarcinoma cell line AsPC-1. In addition, a humanized version of 92R mAb (Srb1) is also able to inhibit growth of CCR9+ T-ALL tumor cells in vivo, increasing survival 2.66-fold. Finally, 92R mAb prevents liver accumulation of infiltrates and reduces tumor cell numbers in already formed infiltrates. Thus, the humanized version of 92R mAb (Srb1), displays therapeutic potential for CCR9+ tumor treatment and might represent one of the first therapeutic antibodies for precision medicine on T-ALL patients.

Overcoming tumor resistance mechanisms in CAR-NK cell therapy.

Despite the impressive results of autologous CAR-T cell therapy in refractory B lymphoproliferative diseases, CAR-NK immunotherapy emerges as a safer, faster, and cost-effective approach with no signs of severe toxicities as described for CAR-T cells. Permanently scrutinized for its efficacy, recent promising data in CAR-NK clinical trials point out the achievement of deep, high-quality responses, thus confirming its potential clinical use. Although CAR-NK cell therapy is not significantly affected by the loss or downregulation of its CAR tumor target, as in the case of CAR-T cell, a plethora of common additional tumor intrinsic or extrinsic mechanisms that could also disable NK cell function have been described. Therefore, considering lessons learned from CAR-T cell therapy, the emergence of CAR-NK cell therapy resistance can also be envisioned. In this review we highlight the processes that could be involved in its development, focusing on cytokine addiction and potential fratricide during manufacturing, poor tumor trafficking, exhaustion within the tumor microenvironment (TME), and NK cell short in vivo persistence on account of the limited expansion, replicative senescence, and rejection by patient's immune system after lymphodepletion recovery. Finally, we outline new actively explored alternatives to overcome these resistance mechanisms, with a special emphasis on CRISPR/Cas9 mediated genetic engineering approaches, a promising platform to optimize CAR-NK cell function to eradicate refractory cancers.

The Role of Tumor Microenvironment in Multiple Myeloma Development and Progression.

Multiple myeloma (MM) is a hematologic cancer characterized by clonal proliferation of plasma cells in the bone marrow (BM). The progression, from the early stages of the disease as monoclonal gammopathy of undetermined significance (MGUS) and smoldering multiple myeloma (SMM) to MM and occasionally extramedullary disease, is drastically affected by the tumor microenvironment (TME). Soluble factors and direct cell-cell interactions regulate MM plasma cell trafficking and homing to the BM niche. Mesenchymal stromal cells, osteoclasts, osteoblasts, myeloid and lymphoid cells present in the BM create a unique milieu that favors MM plasma cell immune evasion and promotes disease progression. Moreover, TME is implicated in malignant cell protection against anti-tumor therapy. This review describes the main cellular and non-cellular components located in the BM, which condition the immunosuppressive environment and lead the MM establishment and progression.

BAY 81-8973 prophylaxis and pharmacokinetics in haemophilia A: Interim results from the TAURUS study.

OBJECTIVES: To report interim data from TAURUS, a study assessing real-world prophylactic treatment with unmodified, full-length recombinant FVIII BAY 81-8973 (Kovaltry® ; Bayer) indicated for haemophilia A. METHODS: TAURUS (NCT02830477) is an international, open-label, prospective, non-interventional, single-arm study with a one-year observation period (target N = 350). Patients have moderate or severe haemophilia A (FVIII ≤5% or ≤1%) and ≥50 exposure days to any FVIII product. Clinician- and patient-reported outcomes are captured on previous product use, changes in prophylaxis dose and dosing frequency, FVIII consumption, reported bleeding rates, treatment satisfaction and adherence, pharmacokinetic (PK) data (if available) and safety data. RESULTS: At cut-off, baseline data were available from 160 patients (89 had ≥6 months of follow-up data). Most patients had severe haemophilia A (85%), infused BAY 81-8973 ≥ 3×/wk (59%) and experienced a median number of total bleeds of 2.0 (non-annualised; 246 days median documentation period). Good levels of treatment satisfaction (Hemo-SATA,P ) and adherence (VERITAS-Pro) were maintained. TAURUS demonstrated a favourable PK profile of BAY 81-8973 in comparison with other standard half-life rFVIIIs and supported the WAPPS PopPK model. No patients developed inhibitors. CONCLUSIONS: TAURUS data demonstrate effective prophylaxis with BAY 81-8973 in the real world without compromising patient satisfaction or adherence.

BCG Therapy of Bladder Cancer Stimulates a Prolonged Release of the Chemoattractant CXCL10 (IP10) in Patient Urine.

Background: Intra-vesical instillation of Bacille Calmette-Guérin (BCG), an attenuated strain of Mycobacterium bovis, is an effective therapy for high-grade non-muscle invasive bladder cancer (NMIBC), which provokes a local immune response resulting in 70% of patients free of relapse after three years. Because non-responder patients usually have a bad prognosis, the early identification of treatment failure is crucial. We hypothesized that, if an effective immune response was taking place in the bladder, soluble factors would be released to the urine many days after BCG instillations. Methods: An extensive panel of cytokines and chemokines released into the urine seven days after every BCG instillation was screened in a cohort of NMIBC patients over three years. Results: The determinations of the urinary concentrations of cytokines, chemokines, and creatinine showed that increasing concentrations of C-X-C motif chemokine 10 (CXCL10) also known as interferon-inducible protein 10 (IP10) could be detected during the six-week induction cycle of BCG-treated patients released into the urine by CD14+ cells. In vitro, CXCL10 facilitated the recruitment of effector immune cells after the BCG-mediated upregulation of CXCR3 in both T- and natural killer (NK)-cells. Conclusions: The high concentrations of chemokine detected one week after the encounter with mycobacteria suggest that the CXCL10 axis might be related to the intensity of the immune anti-tumor response.

Complete Regression of Advanced Pancreatic Ductal Adenocarcinomas upon Combined Inhibition of EGFR and C-RAF.

Five-year survival for pancreatic ductal adenocarcinoma (PDAC) patients remains below 7% due to the lack of effective treatments. Here, we report that combined ablation of EGFR and c-RAF expression results in complete regression of a significant percentage of PDAC tumors driven by Kras/Trp53 mutations in genetically engineered mice. Moreover, systemic elimination of these targets induces toxicities that are well tolerated. Response to this targeted therapy correlates with transcriptional profiles that resemble those observed in human PDACs. Finally, inhibition of EGFR and c-RAF expression effectively blocked tumor progression in nine independent patient-derived xenografts carrying KRAS and TP53 mutations. These results open the door to the development of targeted therapies for PDAC patients.