Population Pharmacokinetics of Monalizumab in Patients With Advanced Solid Tumors.

Monalizumab is a novel, first-in-class humanized immunoglobulin G4 monoclonal antibody immune checkpoint inhibitor that targets the inhibitory CD94/NKG2A receptors. The objectives of this analysis were to develop a population pharmacokinetic (PK) model of monalizumab, evaluate the impact of clinically relevant covariates on monalizumab PK, and provide dose justification for clinical trials. We developed a monalizumab population PK model to characterize the PK properties of monalizumab in patients with advanced solid tumors or head and neck squamous cell carcinoma. Data from clinical studies D419NC00001 (NCT02671435) and IPH2201-203 (NCT02643550) were pooled for the analysis, resulting in a data set of 3066 PK samples derived from 507 subjects. The PK of monalizumab were reasonably described by a 2-compartment model with first-order elimination. Monalizumab generally exhibited linear PK over a dose range of 22.5-750 mg or 10 mg/kg every 2 weeks. The estimate of clearance was ≈0.255 L/day, and apparent volume of distribution was 6.36 L for a typical individual, consistent with previous findings for endogenous immunoglobulin Gs and other therapeutic monoclonal antibodies. Baseline albumin and body weight were identified as significant covariates of clearance; body weight, sex, and smoking status had a significant impact on volume of distribution; and none of these covariates had impact on peripheral volume of distribution. Although these covariates were identified as statistically significant, they are considered to be not clinically meaningful, as changes in monalizumab exposure were <30%. Therefore, no dose adjustments of monalizumab based on patient or disease characteristics are recommended.

CD73-Mediated Immunosuppression Is Linked to a Specific Fibroblast Population That Paves the Way for New Therapy in Breast Cancer.

BACKGROUND: Cancer-associated fibroblasts (CAF) are heterogeneous with multiple functions in breast cancer. Recently, we identified a specific CAF subpopulation (referred to as CAF-S1), which promotes immunosuppression and immunotherapy resistance. METHODS AND RESULTS: Here, by studying a large collection of human samples, we highlight the key function of CD73/NT5E in CAF-S1-mediated immunosuppression in breast cancer. We first reveal that CD73 protein level specifically accumulates in CAF-S1 in breast cancer patients. Interestingly, infiltration of regulatory T lymphocytes (Tregs) is significantly correlated with CD73 expression in stroma but not in epithelium, indicating that CD73 contributes to immunosuppression when expressed in CAF-S1 and not in tumor cells. By performing functional assays based on relevant systems using primary CAF-S1 isolated from patients, we demonstrate that CAF-S1 increase the content in both PD-1+ and CTLA-4+ Tregs. Importantly, the use of a blocking anti-CD73 antibody on CAF-S1 reduces CAF-S1-mediated immunosuppression by preventing expression of these immune checkpoints on Tregs. CONCLUSIONS: Our data support the potential clinical benefit of using both anti-CD73 and immune-checkpoint inhibitors in breast cancer patients for inhibiting CAF-S1-mediated immunosuppression and enhancing anti-tumor immune response.

Association of COVID-19 inflammation with activation of the C5a-C5aR1 axis.

Coronavirus disease 2019 (COVID-19) is a disease caused by infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and has resulted in a pandemic1. The C5a complement factor and its receptor C5aR1 (also known as CD88) have a key role in the initiation and maintenance of several inflammatory responses by recruiting and activating neutrophils and monocytes1. Here we provide a longitudinal analysis of immune responses, including phenotypic analyses of immune cells and assessments of the soluble factors that are present in the blood and bronchoalveolar lavage fluid of patients at various stages of COVID-19 severity, including those who were paucisymptomatic or had pneumonia or acute respiratory distress syndrome. The levels of soluble C5a were increased in proportion to the severity of COVID-19 and high expression levels of C5aR1 receptors were found in blood and pulmonary myeloid cells, which supports a role for the C5a-C5aR1 axis in the pathophysiology of acute respiratory distress syndrome. Anti-C5aR1 therapeutic monoclonal antibodies prevented the C5a-mediated recruitment and activation of human myeloid cells, and inhibited acute lung injury in human C5aR1 knock-in mice. These results suggest that blockade of the C5a-C5aR1 axis could be used to limit the infiltration of myeloid cells in damaged organs and prevent the excessive lung inflammation and endothelialitis that are associated with acute respiratory distress syndrome in patients with COVID-19.

Monalizumab: inhibiting the novel immune checkpoint NKG2A.

The implementation of immune checkpoint inhibitors to the oncology clinic signified a new era in cancer treatment. After the first indication of melanoma, an increasing list of additional cancer types are now treated with immune system targeting antibodies to PD-1, PD-L1 and CTLA-4, alleviating inhibition signals on T cells. Recently, we published proof-of-concept results on a novel checkpoint inhibitor, NKG2A. This receptor is expressed on cytotoxic lymphocytes, including NK cells and subsets of activated CD8+ T cells. Blocking antibodies to NKG2A unleashed the reactivity of these effector cells resulting in tumor control in multiple mouse models and an early clinical trial. Monalizumab is inhibiting this checkpoint in human beings and future clinical trials will have to reveal its potency in combination with other cancer treatment options.

Targeting natural killer cells in solid tumors.

Natural killer (NK) cells are innate lymphoid cells endowed with cytolytic activity and a capacity to secrete cytokines and chemokines. Several lines of evidence suggest that NK cells play an important role in anti-tumor immunity. Some therapies against hematological malignacies make use of the immune properties of NK cells, such as their ability to kill residual leukemic blasts efficiently after conditioning during haploidentical hematopoietic stem cell transplantation. However, knowledge on NK cell infiltration and the status of NK cell responsiveness in solid tumors is limited so far. The pro-angiogenic role of the recently described NK cell-like type 1 innate lymphoid cells (ILC1s) and their phenotypic resemblance to NK cells are confounding factors that add a level of complexity, at least in mice. Here, we review the current knowledge on the presence and function of NK cells in solid tumors as well as the immunotherapeutic approaches designed to harness NK cell functions in these conditions, including those that aim to reinforce conventional anti-tumor therapies to increase the chances of successful treatment.

[Natural killer cells: promising targets in cancer therapy]. / Les cellules natural killer : des cibles prometteuses dans la thérapie contre le cancer.

TITLE: Les cellules natural killer : des cibles prometteuses dans la thérapie contre le cancer. ABSTRACT: L'immuno-oncologie est une approche d'immunothérapie novatrice qui change le traitement des cancers en stimulant la capacité du système immunitaire à reconnaître et éliminer les cellules tumorales. Cette approche a pour but de mettre en place une immuno-surveillance anti-tumorale durable chez des patients pour lesquels les thérapies conventionnelles ont échoué.

NKG2A Blockade Potentiates CD8 T Cell Immunity Induced by Cancer Vaccines.

Tumor-infiltrating CD8 T cells were found to frequently express the inhibitory receptor NKG2A, particularly in immune-reactive environments and after therapeutic cancer vaccination. High-dimensional cluster analysis demonstrated that NKG2A marks a unique immune effector subset preferentially co-expressing the tissue-resident CD103 molecule, but not immune checkpoint inhibitors. To examine whether NKG2A represented an adaptive resistance mechanism to cancer vaccination, we blocked the receptor with an antibody and knocked out its ligand Qa-1b, the conserved ortholog of HLA-E, in four mouse tumor models. The impact of therapeutic vaccines was greatly potentiated by disruption of the NKG2A/Qa-1b axis even in a PD-1 refractory mouse model. NKG2A blockade therapy operated through CD8 T cells, but not NK cells. These findings indicate that NKG2A-blocking antibodies might improve clinical responses to therapeutic cancer vaccines.

Anti-NKG2A mAb Is a Checkpoint Inhibitor that Promotes Anti-tumor Immunity by Unleashing Both T and NK Cells.

Checkpoint inhibitors have revolutionized cancer treatment. However, only a minority of patients respond to these immunotherapies. Here, we report that blocking the inhibitory NKG2A receptor enhances tumor immunity by promoting both natural killer (NK) and CD8+ T cell effector functions in mice and humans. Monalizumab, a humanized anti-NKG2A antibody, enhanced NK cell activity against various tumor cells and rescued CD8+ T cell function in combination with PD-x axis blockade. Monalizumab also stimulated NK cell activity against antibody-coated target cells. Interim results of a phase II trial of monalizumab plus cetuximab in previously treated squamous cell carcinoma of the head and neck showed a 31% objective response rate. Most common adverse events were fatigue (17%), pyrexia (13%), and headache (10%). NKG2A targeting with monalizumab is thus a novel checkpoint inhibitory mechanism promoting anti-tumor immunity by enhancing the activity of both T and NK cells, which may complement first-generation immunotherapies against cancer.

A phase 1 study of lirilumab (antibody against killer immunoglobulin-like receptor antibody KIR2D; IPH2102) in patients with solid tumors and hematologic malignancies.

PURPOSE: Anti-KIR monoclonal antibodies (mAbs) can enhance the antitumor responses of natural killer (NK) cells. We evaluated the safety of the anti-KIR2D mAb lirilumab in patients with various cancers. EXPERIMENTAL DESIGN: Thirty-seven patients with hematological malignancies (n = 22) or solid tumors (n = 15) were included in the study. Dose escalation (0.015 to 10 mg/kg) was conducted following a 3 + 3 design. Patients were scheduled to receive four cycles of treatment. In a second (extension) phase 17 patients were treated at 0.015 (n = 9) or 3 mg/kg (n = 8). RESULTS: No dose-limiting toxicity was recorded. The most frequent lirilumab-related adverse events were pruritus (19%), asthenia (16%), fatigue (14%), infusion-related reaction (14%), and headache (11%), mostly mild or moderate. Pharmacokinetics was dose-dependent and linear, with minimal accumulation resulting from the 4-weekly repeated administrations. Full KIR occupancy (>95%) was achieved with all dosages, and the duration of occupancy was dose-related. No significant changes were observed in the number or distribution of lymphocyte subpopulations, nor was any reduction in the distribution of KIR2D-positive NK cells. CONCLUSIONS: This phase 1 trial demonstrated the satisfactory safety profile of lirilumab up to doses that enable full and sustained blockade of KIR.

Roles, responsibilities and characteristics of lay community health workers involved in diabetes prevention programmes: A systematic review.

AIM: To examine the characteristics of community health workers (CHWs) involved in diabetes prevention programmes (DPPs) and their contributions to expected outcomes. METHODS: Electronic databases including PubMed-MEDLINE, EBSCOHost, and SCOPUS/EMBASE were searched for studies published between January 2000 and March 2016. All studies that used CHWs to implement DPP in ≥18-year-old participants without diabetes but at high risk for developing the condition, irrespective of the study design, setting or outcomes measured, were included. Results were synthesized narratively. RESULTS: Forty papers of 30 studies were identified. Studies were mainly community-based and conducted in minority populations in USA. Sample sizes ranged from 20 participants in a single community to 2369 participants in 46 communities. Although CHWs were generally from the local community, their qualifications, work experience and training received differed across studies. Overall the training was culturally sensitive and/or appropriate, covering topics such as the importance of good nutrition and the benefits of increased physical activity, communication and leadership. CHWs delivered a variety of interventions and also screened or recruited participants. The shared culture and language between CHWs and participants likely contributed to better programme implementation and successful outcomes. CONCLUSIONS: The complexity of DPPs and the diverse CHW roles preclude attributing specific outcomes to CHW involvement. Nevertheless, documenting potential CHW roles and the relevant training required may optimise CHW contributions and facilitate their involvement in DPPs in the future.

Kinetics of Cytotoxic Lymphocytes Reconstitution after Induction Chemotherapy in Elderly AML Patients Reveals Progressive Recovery of Normal Phenotypic and Functional Features in NK Cells.

NK cells are defective in acute myeloid leukemia (AML) at diagnosis. Here, we studied the kinetic of expression of the major activating and inhibitory receptors of NK, CD8 T, and γδ T cells in patients undergoing chemotherapy (CT) for the treatment of AML (n = 29). We showed that NK cells are the main affected population at diagnosis and that expression of activating receptors is partially restored within a few weeks after CT. CD8 T cells and γδ T cells are only weakly affected at diagnosis. Killer cell immunoglobulin-like receptor expression by NK cells, but not NKG2A and CD85j, was downregulated. Interestingly, the development of NK cells appeared altered as the most immature CD56bright NK cells were seriously underrepresented. Finally, we showed that NK cell functions were only partially restored 6 weeks after CT as degranulation capabilities of NK cells recovered, whereas cytokine production remained low. Our data point out NK cells as antitumor effectors peculiarly hampered by leukemic cells. This study may indicate a timeline when NK-mediated therapies or other immunotherapies could be performed, particularly for patients excluded of hematopoietic stem cell transplantation.

Effects of anti-NKG2A antibody administration on leukemia and normal hematopoietic cells.

Natural killer cells are key cells of the innate immune system. Natural killer cell receptor repertoires are diversified by a stochastic expression of killer-cell-immunoglobulin-like receptors and lectin-like receptors such as NKG2 receptors. All individuals harbor a subset of natural killer cells expressing NKG2A, the inhibitory checkpoint receptor for HLA-E. Most neoplastic and normal hematopoietic cells express HLA-E, the inhibitory ligand of NKG2A. A novel anti-human NKG2A antibody induced tumor cell death, suggesting that the antibody could be useful in the treatment of cancers expressing HLA-E. We found that immunodeficient mice, co-infused with human primary leukemia or Epstein-Barr virus cell lines and NKG2A(+) natural killer cells, pre-treated with anti-human NKG2A, were rescued from disease progression. Human NKG2A(+) natural killer cells reconstituted in immunodeficient mice after transplantation of human CD34(+) cells. These natural killer cells are able to kill engrafted human primary leukemia or Epstein-Barr virus cell lines by lysis after intraperitoneal administration of anti-human NKG2A. Thus, this anti-NKG2A may exploit the anti-leukemic action of the wave of NKG2A(+) natural killer cells recovering after hematopoietic stem cell transplants or adoptive therapy with natural killer cell infusions from matched or mismatched family donors after chemotherapy for acute leukemia, without the need to search for a natural killer cell alloreactive donor.

A Phase I Trial of the Anti-KIR Antibody IPH2101 and Lenalidomide in Patients with Relapsed/Refractory Multiple Myeloma.

PURPOSE: Natural killer (NK) cells may play an important role in the immune response to multiple myeloma; however, multiple myeloma cells express killer immunoglobulin-like receptor (KIR) ligands to prevent NK cell cytotoxicity. Lenalidomide can expand and activate NK cells in parallel with its direct effects against multiple myeloma; however, dexamethasone may impair these favorable immunomodulatory properties. IPH2101, a first-in-class antiinhibitory KIR antibody, has acceptable safety and tolerability in multiple myeloma as a single agent. The present work sought to characterize lenalidomide and IPH2101 as a novel, steroid-sparing, dual immune therapy for multiple myeloma. EXPERIMENTAL DESIGN: A phase I trial enrolled 15 patients in three cohorts. Lenalidomide was administered per os at 10 mg on cohort 1 and 25 mg on cohorts 2 and 3 days 1 to 21 on a 28-day cycle with IPH2101 given intravenously on day 1 of each cycle at 0.2 mg/kg in cohort 1, 1 mg/kg in cohort 2, and 2 mg/kg in cohort 3. No corticosteroids were utilized. The primary endpoint was safety, and secondary endpoints included clinical activity, pharmacokinetics (PK), and pharmacodynamics (PD). RESULTS: The biologic endpoint of full KIR occupancy was achieved across the IPH2101 dosing interval. PD and PK of IPH2101 with lenalidomide were similar to data from a prior single-agent IPH2101 trial. Five serious adverse events (SAE) were reported. Five objective responses occurred. No autoimmunity was seen. CONCLUSIONS: These findings suggest that lenalidomide in combination with antiinhibitory KIR therapy warrants further investigation in multiple myeloma as a steroid-sparing, dual immune therapy. This trial was registered at www.clinicaltrials.gov (reference: NCT01217203).

Daratumumab-mediated lysis of primary multiple myeloma cells is enhanced in combination with the human anti-KIR antibody IPH2102 and lenalidomide.

Despite recent treatment improvements, multiple myeloma remains an incurable disease. Since antibody-dependent cell-mediated cytotoxicity is an important effector mechanism of daratumumab, we explored the possibility of improving daratumumab-mediated cell-mediated cytotoxicity by blocking natural killer cell inhibitory receptors with the human monoclonal anti-KIR antibody IPH2102, next to activation of natural killer cells with the immune modulatory drug lenalidomide. In 4-hour antibody-dependent cell-mediated cytotoxicity assays, IPH2102 did not induce lysis of multiple myeloma cell lines, but it did significantly augment daratumumab-induced myeloma cell lysis. Also in an ex vivo setting, IPH2102 synergistically improved daratumumab-dependent lysis of primary myeloma cells in bone marrow mononuclear cells (n=21), especially in patients carrying the FcγRIIIa-158F allele or the FcγRIIa-131R allele, who bind IgG1 with lower affinity than patients carrying the FcγRIIIa-158V allele or the FcγRIIa-131H allele. Finally, a further synergistically improved myeloma cell lysis with the daratumumab-IPH2102 combination was observed by adding lenalidomide, which suggests that more effective treatment strategies can be designed for multiple myeloma by combining daratumumab with agents that independently modulate natural killer cell function.

Anti-KIR antibody enhancement of anti-lymphoma activity of natural killer cells as monotherapy and in combination with anti-CD20 antibodies.

Natural killer (NK) cells mediate antilymphoma activity by spontaneous cytotoxicity and antibody-dependent cell-mediated cytotoxicity (ADCC) when triggered by rituximab, an anti-CD20 monoclonal antibody (mAb) used to treat patients with B-cell lymphomas. The balance of inhibitory and activating signals determines the magnitude of the efficacy of NK cells by spontaneous cytotoxicity. Here, using a killer-cell immunoglobulin-like receptor (KIR) transgenic murine model, we show that blockade of the interface of inhibitory KIRs with major histocompatibility complex (MHC) class I antigens on lymphoma cells by anti-KIR antibodies prevents a tolerogenic interaction and augments NK-cell spontaneous cytotoxicity. In combination with anti-CD20 mAbs, anti-KIR treatment induces enhanced NK-cell-mediated, rituximab-dependent cytotoxicity against lymphoma in vitro and in vivo in KIR transgenic and syngeneic murine lymphoma models. These results support a therapeutic strategy of combination rituximab and KIR blockade through lirilumab, illustrating the potential efficacy of combining a tumor-targeting therapy with an NK-cell agonist, thus stimulating the postrituximab antilymphoma immune response.

A phase 1 trial of the anti-KIR antibody IPH2101 in patients with relapsed/refractory multiple myeloma.

Natural killer (NK) cells elicit cytotoxicity against multiple myeloma (MM); however, MM cells express HLA class I molecules as ligands to NK cell inhibitory killer immunoglobulin-like receptors (KIRs) as a means of immunoevasion. KIR-ligand mismatch may improve outcomes in allogeneic transplantation for MM. Extrapolating on this concept, we conducted a phase 1 trial of IPH2101, an anti-KIR antibody, in patients with relapsed/refractory MM. IPH2101 was administered intravenously every 28 days in 7 dose-escalated cohorts (0.0003-3 mg/kg) for up to 4 cycles. Pharmacokinetic, pharmacodynamic, and correlative immunologic studies were completed. A total of 32 patients were enrolled. The biologic endpoint of full KIR2D occupancy across the dosing cycle was achieved without dose-limiting toxicity or maximally tolerated dose. One severe adverse event was noted. Pharmacokinetic and pharmacodynamic findings approximated preclinical predictions, and IPH2101 enhanced ex vivo patient-derived NK cell cytotoxicity against MM. No objective responses were seen. No evidence of autoimmunity was observed. These findings suggest that IPH2101 is safe and tolerable at doses that achieve full inhibitory KIR saturation, and this approach warrants further development in MM. This trial was registered at www.clinicaltrials.gov as #NCT00552396.

A phase 1 trial of the anti-inhibitory KIR mAb IPH2101 for AML in complete remission.

IPH2101 is an anti-killer inhibitory receptor (anti-KIR) mAb that can block KIR-mediated inhibition of natural killer (NK) cells to enhance cytotoxicity against acute myeloid leukemia blasts. We have conducted a phase 1 study of IPH2101 in elderly patients with acute myeloid leukemia in first complete remission. Patients received escalating doses (0.0003-3 mg/kg) of IPH2101 following a 3 + 3 design. Safety, toxicity (primary end points), pharmacokinetics, outcome, and immunologic correlates were evaluated. Twenty-three patients (median age, 71 years), were enrolled. Adverse events were mild and transient, consisting mainly of infusion syndrome and erythema. The maximum tolerated dose was not reached, although full KIR saturation (> 90%) was sustained for more than 2 weeks at 1 and 3 mg/kg. There was a clear correlation between mAb exposure and KIR occupancy. Neither hematologic toxicity nor significant changes in the numbers and distribution of lymphocyte subsets, NK cell receptor expression, or in vitro cytotoxicity were seen. At the highest dose levels (0.3, 1, and 3 mg/kg), transient increases in TNF-α and MIP-1ß serum concentrations and NK cell CD69 expression were observed. Overall and relapse-free survival in the present study compared favorably to reports in comparable patient populations. We conclude that IPH2101 administration is safe and can block KIR for prolonged periods of time with limited side effects. Registered with the European Union Drug Regulating Authorities Clinical Trials (EUDRACT) as 2005-005298-31.

IPH2101, a novel anti-inhibitory KIR antibody, and lenalidomide combine to enhance the natural killer cell versus multiple myeloma effect.

Multiple myeloma (MM) patients who receive killer cell Ig-like receptor (KIR) ligand-mismatched, T cell-depleted, allogeneic transplantation may have a reduced risk of relapse compared with patients who receive KIR ligand-matched grafts, suggesting the importance of this signaling axis in the natural killer (NK) cell-versus-MM effect. Expanding on this concept, IPH2101 (1-7F9), an anti-inhibitory KIR mAb, enhances NK-cell function against autologous MM cells by blocking the engagement of inhibitory KIR with cognate ligands, promoting immune complex formation and NK-cell cytotoxicity specifically against MM cell targets but not normal cells. IPH2101 prevents negative regulatory signals by inhibitory KIR, whereas lenalidomide augments NK-cell function and also appears to up-regulate ligands for activating NK-cell receptors on MM cells. Lenalidomide and a murine anti-inhibitory NK-cell receptor Ab mediate in vivo rejection of a lenalidomide-resistant tumor. These mechanistic, preclinical data support the use of a combination of IPH2101 and lenalidomide in a phase 2 trial for MM.

Human breast cancer cells enhance self tolerance by promoting evasion from NK cell antitumor immunity.

NK cells are a major component of the antitumor immune response and are involved in controlling tumor progression and metastases in animal models. Here, we show that dysfunction of these cells accompanies human breast tumor progression. We characterized human peripheral blood NK (p-NK) cells and malignant mammary tumor-infiltrating NK (Ti-NK) cells from patients with noninvasive and invasive breast cancers. NK cells isolated from the peripheral blood of healthy donors and normal breast tissue were used as controls. With disease progression, we found that expression of activating NK cell receptors (such as NKp30, NKG2D, DNAM-1, and CD16) decreased while expression of inhibitory receptors (such as NKG2A) increased and that this correlated with decreased NK cell function, most notably cytotoxicity. Importantly, Ti-NK cells had more pronounced impairment of their cytotoxic potential than p-NK cells. We also identified several stroma-derived factors, including TGF-ß1, involved in tumor-induced reduction of normal NK cell function. Our data therefore show that breast tumor progression involves NK cell dysfunction and that breast tumors model their environment to evade NK cell antitumor immunity. This highlights the importance of developing future therapies able to restore NK cell cytotoxicity to limit/prevent tumor escape from antitumor immunity.