Neutrophil-to-lymphocyte ratio as an early marker of outcomes in patients with recurrent oral squamous cell carcinoma treated with nivolumab.

The immune checkpoint inhibitor (ICI), nivolumab, has revolutionised the treatment of recurrent and metastatic oral cancer. However, the response rate to ICIs remains low, and identifying predictors of nivolumab response is critical. Although the neutrophil-to-lymphocyte ratio (NLR) has been suggested as a predictive marker of nivolumab response in patients with various types of cancer, its utility in oral squamous cell carcinoma (OSCC) has not been elucidated. In this retrospective multicentre cohort study, we evaluated the association between NLR and outcome of nivolumab treatment in 64 patients with OSCC treated between 2017 and 2020. The objective response and disease control rates were 25.1% and 32.9%, respectively. The rates for complete and partial responses were 15.7% (10/64) and 9.4% (6/64), respectively; stable and progressive disease rates were 7.8% (5/64) and 67.1% (43/64), respectively. Complete and partial responses were classified as responders, and stable and progressive diseases were classified as non-responders. The median (range) pre-treatment NLR among responders was 4.3 (2.8-8.0), which decreased to 4.0 (2.6-6.3) after nivolumab treatment, and the median (range) pre-treatment NLR among non-responders was 5.1 (2.7-7.9), which increased to 6.4 (4.0-14.0) with tumour growth. Moreover, overall survival was significantly worse in the group with a higher post-treatment NLR (≥5) than in the group with a lower NLR (<5). Patients with a post-treatment NLR of ≥6 had worse outcomes for salvage chemotherapy following nivolumab treatment. Thus, post-treatment NLR could be a useful marker for predicting the response to nivolumab treatment or salvage chemotherapy in patients with OSCC.

PD-1/PD-L1 inhibition promotes hepatic regeneration in small-for-size liver following extended hepatectomy.

BACKGROUND: Small-for-size syndrome following liver surgery is characterized by compromised liver regeneration. Liver macrophages play key roles in initiating liver regeneration, and modulation of the immune microenvironment through macrophages may accelerate liver regeneration. In our current study, we aimed to explore the involvement of innate immunity after extended hepatectomy in rats and humans, and to test the effect of immunity modulation on small-for-size liver regeneration in rats. METHODS: Serum programmed cell death protein ligand 1 (PD-L1) was measured after major hepatectomy and minor hepatectomy in humans and rats. Liver regeneration in rats was assessed using liver-to-body weight ratio and kinetic growth rate, antigen Ki67 and proliferating cell nuclear antigen (PCNA), and macrophage polarization was assessed by inducible nitric oxide synthase (iNOS), cluster of differentiation protein 163 (CD163) expression by immunohistochemistry (IHC) and iNOS/CD163 ratio. Rat hepatocyte BRL or human hepatocyte LO2 were co-cultured with rat bone marrow-derived macrophages or human macrophages THP-1. BMS-1 or Nivolumab were used to block programmed cell death protein 1 (PD-1)/PD-L1 in vitro and in vivo. RESULTS: PD-L1 expressions were significantly higher following major hepatectomy compared to minor resection in both humans and rats; compromised liver regeneration after extended hepatectomy in rats was associated with PD-L1 upregulation and M2 macrophage polarization. M1 macrophages increased proliferation of hepatocytes through interleukin-6 (IL-6), and M2 macrophages decreased hepatocyte proliferation; blocking PD-1/PD-L1 reversed the effect of M2 macrophages on the survival of hepatocytes in vitro and promoted liver growth in rats through M1 macrophage polarization. CONCLUSION: Compromised hepatic regeneration following extended hepatectomy is characterized by M2 macrophage polarization and upregulated PD-L1 expression. Blocking PD-1/PD-L1 may enhance small-for-size liver regeneration by inducing M1 macrophage polarization.

Exploring the conformational dynamics of PD1 in complex with different ligands: What we can learn for designing novel PD1 signaling blockers?

Activation of T cells triggers the expression of regulatory molecules like the programmed cell death 1 (PD1) protein. The association of PD1 with the natural ligands PDL1 and PDL2 induces an inhibitory signal that prevents T cells from proliferating and exerting effector functions. However, little is known about how the binding of the ligands induce the PD1 inhibitory signal over T cells effector functions. Here, we explore the dynamics of PD1 free, and in complex with different PDL1 variants as well as the therapeutic antibodies nivolumab and pembrolizumab in order to assess the conformational changes in PD1 related to the signaling process. Our simulations suggest a pre-conformational selection mechanism for the binding of the different PDL1 variants, while an induced-fit model fits better for the molecular recognition process of the therapeutic antibodies. A deep analysis of the changes on PD1 movement upon the binding to different ligands revealed that as larger is the difference in the conformation adopted by loop C'D with respect to the complex with PDL1 is higher the ligand ability to reduce the PD1 inhibitory signaling. This behavior suggests that targeting specific conformations of this loop can be useful for designing therapies able to recover T cells effector functions.

Checkpoint Blockade in Melanoma Patients With Underlying Chronic Lymphocytic Leukemia.

Chronic lymphocytic leukemia (CLL) is associated with immune dysfunction and an increased risk of melanoma. For patients with metastatic melanoma, immunotherapy with checkpoint blocking antibodies is a standard of care. In patients with concomitant CLL and metastatic melanoma, it is not known whether CLL might influence the antimelanoma efficacy or immune-related toxicities of immune checkpoint blockade. Fifteen patients with locally advanced or metastatic melanoma and a concomitant diagnosis of CLL who received pembrolizumab or ipilimumab with or without nivolumab for the treatment of their melanoma at Memorial Sloan Kettering Cancer Center between January 1, 2010, and January 1, 2017, were retrospectively identified. Clinical characteristics including absolute lymphocyte counts during therapy were recorded along with a response to treatment (objective radiographic response, progression-free survival, and adverse events) for each patient. Of 9 response-evaluable patients treated with ipilimumab, 3 (33%) had a partial response, 1 (11%) had stable disease, and 5 (56%) developed progressive disease. Objective tumor responses were also observed with single-agent therapy pembrolizumab and with combination therapy of nivolumab and ipilimumab. Grade 3 or 4 toxicity was observed in 6 of 15 patients (40%), including diarrhea, transaminitis, rash, and hemolytic anemia. Although our retrospective assessment was limited, there was no evidence that CLL responded to the checkpoint blockade. This case series demonstrates that ipilimumab, pembrolizumab, and combined ipilimumab and nivolumab therapies show clinical activity in patients with melanoma and concomitant CLL, at rates consistent with those previously reported. This population may warrant closer surveillance for hematologic immune-related toxicities such as autoimmune hemolytic anemia.

Topical Delivery of Nivolumab, a Therapeutic Antibody, by Fractional Laser and Pneumatic Injection.

BACKGROUND AND OBJECTIVES: PD-L1 is a tumor ligand that binds to the PD-1 receptor on immune cells, thereby inhibiting the antitumor immune response. The antibody nivolumab is a PD-1 inhibitor, Food and Drug Administration approved for systemic treatment of several aggressive cancer types. Topically applied nivolumab may hold potential as a future strategy to treat keratinocyte cancer, but its molecular properties preclude unassisted topical uptake. The aim of this study was to investigate uptake and biodistribution of topically delivered nivolumab, assisted by two physical enhancement techniques with different delivery kinetics; ablative fractional laser (AFL) and electronically controlled pneumatic injection (EPI). STUDY DESIGN/MATERIALS AND METHODS: In vitro porcine skin was exposed to CO2 AFL (20 mJ/mb, 5% density), followed by passive diffusion of nivolumab in a Franz cell (1 mg/ml, 18 hours, n = 6) or treated with EPI (4 bar) for immediate delivery of nivolumab (1 mg/ml, 10 minutes, n = 6). The resulting nivolumab skin concentrations were quantified by enzyme-linked immunosorbent assay (ELISA) at three skin depths (100, 500, and 1500 µm), comparing the uptake from assisted delivery with intact skin. Biodistribution of nivolumab in the skin for all interventions was visualized by laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) and fluorescence microscopy. RESULTS: Delivery of nivolumab by AFL-assisted passive diffusion and immediate EPI both resulted in significantly enhanced uptake of nivolumab in all skin depths compared with intact skin (P < 0.05). With AFL, nivolumab concentrations reached 86.3 µg/cm3 (100 µm), 105.8 µg/cm3 (500 µm), and 19.3 µg/cm3 (1500 µm), corresponding to 2-10% of the applied concentration, with the highest deposition in the mid dermis. Immediate EPI delivered 429.4 µg/cm3 (100 µm), 584.9 µg/cm3 (500 µm), and 295.9 µg/cm3 (1500 µm) into the skin, corresponding to 29-58% of the applied nivolumab concentration. From qualitative visualization of the biodistribution, it appeared that nivolumab distributed in a horizontal and continuous homogenous band in the upper and mid dermis through AFL-exposed skin, whereas EPI-delivery showed a deep focal deposition extending into the deep dermis. CONCLUSIONS: AFL-assisted passive diffusion and immediate EPI-assisted delivery show the potential to deliver therapeutic antibodies locally. Future in vivo and pharmacokinetic studies would reveal the full potential for topical antibody delivery by energy-based devices. Lasers Surg. Med. © 2020 Wiley Periodicals LLC.

Epitope and Paratope Mapping of PD-1/Nivolumab by Mass Spectrometry-Based Hydrogen-Deuterium Exchange, Cross-linking, and Molecular Docking.

Programmed cell death-1 (PD-1), an antigen co-receptor on cell surfaces, is one of the conspicuous immune checkpoints. Nivolumab, a monoclonal antibody therapeutic approved by the FDA, binds to PD-1 and efficiently blocks its pathways. In this study, an integrated approach was developed to map the epitope/paratope of PD-1/nivolumab. The approach includes hydrogen-deuterium exchange mass spectrometry (HDX-MS) followed by electron-transfer dissociation (ETD), chemical cross-linking, and molecular docking. HDX-ETD offers some binding-site characterization with amino acid resolution. Chemical cross-linking provides complementary information on one additional epitope (i.e., the BC-loop) and a potential paratope at the N-terminus of the heavy chain. Furthermore, cross-linking identifies another loop region (i.e., the C'D-loop) that undergoes a remote conformational change. The distance restraints derived from the cross-links enable building high-confidence models of PD-1/nivolumab, evaluated with respect to a resolved crystal structure. This integrated strategy is an opportunity to characterize comprehensively other antigen-antibody interactions, to enable the understanding of binding mechanisms, and to design future antibody therapeutics.

Nivolumab for the treatment of hepatocellular carcinoma.

INTRODUCTION: Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related deaths worldwide and up to recently, sorafenib was the only approved systemic treatment options. In recent years, many other treatment options have received approval for advanced HCC, including nivolumab, a Programmed-Death-1 (PD-1) inhibitor. AREAS COVERED: We review the current treatment landscape of HCC, an overview of the characteristics of nivolumab and current ongoing and completed trials of nivolumab. EXPERT OPINION: Nivolumab is generally well tolerated and has modest single-agent activity as a monotherapy in advanced HCC. Further studies are required to better explore its role as part of combination approaches, in adjuvant/neoadjuvant setting, as well as to understand the impact of sequencing of its use with other systemic therapy options.

Monitoring PD-1-Blocking Antibodies Bound to T Cells Derived from a Drop of Peripheral Blood.

Immune checkpoint inhibitors, including PD-1-blocking antibodies, have significantly improved treatment outcomes in various types of cancer. The pharmacological efficacy of these immunotherapies is long lasting, extending even beyond the discontinuation of their injections, due to persistent blood concentrations. Here we developed a simple flow cytometry assay to evaluate the T cell binding status of the PD-1-blocking antibodies nivolumab and pembrolizumab. Like a glucose test, this assay requires just a single drop of peripheral blood. Visualizing antibody binding on T cells is more reliable than measuring antibody blood concentrations. In addition, if necessary, we can potentially analyze many distinctive immune-related markers on T cells bound to PD-1-blocking antibodies. Thus, this is a simple and minimally invasive strategy to analyze the pharmacological effect of PD-1-blocking antibodies in cancer patients.

Loss of nivolumab binding to T cell PD-1 predicts relapse of Hodgkin lymphoma.

Nivolumab is effective in the treatment of classical Hodgkin lymphoma that relapsed after allogeneic hematopoietic stem cell transplantation (SCT) with the risk of graft-versus-host disease; however, the optimal time and dose of nivolumab administration remain to be investigated. Nivolumab binding to PD-1 masks flowcytometric detection of PD-1 by the anti-PD-1 monoclonal antibody EH12.1. Using this method, we monitored nivolumab binding on T cells after nivolumab treatment in a patient with classical Hodgkin lymphoma relapsed after allogeneic SCT. Nivolumab was effective while prolonged nivolumab binding was evident, but restoration of PD-1 staining predicted tumor relapse. Flowcytometric monitoring of nivolumab binding on T cells could be a promising biomarker for predicting tumor relapse and determining the timing of nivolumab administration.

Multiparameter Flow Cytometry Assay for Quantification of Immune Cell Subsets, PD-1 Expression Levels and PD-1 Receptor Occupancy by Nivolumab and Pembrolizumab.

We report the development and validation of a 12 parameter immunofluorescence flow cytometry method for the sensitive determination of cell concentrations, their expression of PD-1, and PD-1 receptor occupancy. Cell subsets include CD4+ and CD8+ -T-cells, B-cells, natural killer cells, classical-, intermediate- and non-classical monocytes, and myeloid- and plasmacytoid dendritic cells. Cells were isolated from peripheral blood by density gradient centrifugation. The validation parameters included specificity, linearity, limit of quantification, precision, biological within- and between subject variations. The lower limit of quantification was 5.0% of PD-1+ cells. Samples were stable for at least 153 days of storage at -80°C. The clinical applicability of the method was demonstrated in 11 advanced cancer patients by the successful determination of immune cell concentrations, relative number of PD-1+ immune cells, and number of PD-1 molecules per immune cell. Shortly after infusion of nivolumab, receptor occupancy on CD8+ -T-cells was 98%. Similar values were found predose cycle 2, suggesting receptor occupancy remained high throughout the entire cycle. © 2019 International Society for Advancement of Cytometry.

Precision medicine becomes reality-tumor type-agnostic therapy.

Precision medicine just witnessed two breakthroughs in oncology in 2017. Pembrolizumab (Keytruda), Merck's anti-programmed cell death-1 (PD-1) monoclonal antibody (mAb), received accelerated approval in May 2017 by the US Food and Drug Administration for the treatment of adult and pediatric patients with unresectable or metastatic solid tumors that have been identified as having microsatellite instability-high (MSI-H) or deficient DNA mismatch repair (dMMR). Shortly after, nivolumab (Opdivo), Bristol-Myers Squibb's anti-PD-1 mAb, gained an accelerated approval in August 2017 for adult and pediatric patients with MSI-H or dMMR metastatic colorectal cancer that has progressed after standard chemotherapy. These regulatory approvals marked an important milestone that a cancer treatment may be approved based on a common biomarker rather than the anatomic location in the body where the tumor originated, and therefore established a precedent for tumor type-agnostic therapy. In the 2017 American Society for Clinical Oncology annual meeting, larotrectinib (LOXO-101), Loxooncology's oral, potent, and selective inhibitor of tropomyosin receptor kinases (TRK), demonstrated unprecedented efficacy on unresectable or metastatic solid tumors with neurotrophic tropomyosin receptor kinase (NTRK)-fusion proteins in adult and pediatric patients. Both the anti-PD-1 mAbs and the TRK-targeting therapies share some basic features: (a) biomarker-based, well-defined rare patient population; (b) exceptionally high clinical efficacy, e.g., near 40% overall response rate (ORR) for pembrolizumab across 15 tumor types with MSI-H/dMMR and 75% ORR for larotrectinib across more than 12 tumor types with NTRK-fusion proteins; (c) durable responses lasting at least 6 months with complete responses observed; and (d) parallel development in adult and pediatric populations. With increasing accessibility to genetic analysis tools such as next-generation sequencing, tumor type-agnostic therapy has become a reality, both during clinical development and in clinical practice. Adjustments in our approaches to developing new anti-cancer drugs and to adopting these new cancer treatments in clinical practice need to occur in order to prepare ourselves for the new era of precision medicine.