Enhancing anti-CD274 (PD-L1) targeting through combinatorial immunotherapy with bispecific antibodies and fusion proteins: from preclinical to phase II clinical trials.

INTRODUCTION: Immune checkpoint inhibitors have achieved great success in the treatment of many different types of cancer. Programmed cell death protein ligand 1 (PD-L1, CD274) is a major immunosuppressive immune checkpoint and a target for several already approved monoclonal antibodies. Despite this, novel strategies are under development, as the overall response remains low. AREAS COVERED: In this review, an overview of the current biomarkers for response to PD-L1 inhibitor treatment is given, followed by a discussion of potential novel biomarkers, including tumor mutational burden and circulating tumor DNA. Combinatorial immunotherapy is a potential novel strategy to increase the response to PD-L1 inhibitor treatment and currently, several interesting bispecific antibodies as well as bispecific fusion proteins are undergoing early clinical investigation. We focus on substances targeting PD-L1 and a secondary target, and a secondary immunomodulatory target like CTLA-4, TIGIT, or CD47. EXPERT OPINION: Overall, the presented studies show anti-tumor activity of these combinatorial immunotherapeutic approaches. However, still relatively low response rates suggest a need for better biomarkers.

Real-world Data of Palliative First-line Checkpoint Inhibitor Therapy for Head and Neck Cancer.

BACKGROUND/AIM: Pembrolizumab alone or combined with chemotherapy is now approved in PD-L1-positive patients with recurrent or metastatic squamous cell carcinoma of the head and neck (SCCHN). Since real-world data are pending, our goal was to evaluate the efficacy and safety of immune checkpoint inhibitor (CPI) therapy in an unselected cohort of patients with SCCHN. PATIENTS AND METHODS: We analyzed 78 patients with recurrent or metastatic SCCHN from three Austrian cancer centers that received CPI therapy alone or with chemotherapy as palliative first-line systemic treatment for this retrospective study. Patient characteristics, details on treatment, and survival were analyzed by a chart-based review. RESULTS: Of the 78 patients analyzed, 55 patients were treated with CPI alone (45 with Pembrolizumab, 10 with Nivolumab) and 23 patients received chemotherapy with a platinum and 5-FU in addition to CPI. With a median follow-up of twelve months, the median PFS of all patients was 4 months [95% confidence interval (CI)=2.2-5.8] and the median OS was 11 months (95% CI=7.1-14.9). The overall response and disease control rates were 20.5% and 46.1%, respectively. There was no statistically significant difference in clinical outcome between patient groups with a different combined positive score (CPS). The rate of reported immune related adverse events was comparable to existing data. CONCLUSION: Our findings confirm the results of the KEYNOTE-048 trial that CPI therapy alone or together with chemotherapy is an effective treatment for patients with recurrent or metastatic CPS-positive SCCHN.

Recent Advances in Pancreatic Cancer: Novel Prognostic Biomarkers and Targeted Therapy-A Review of the Literature.

Pancreatic adenocarcinoma carries a devastating prognosis. For locally advanced and metastatic disease, several chemotherapeutic regimens are currently being used. Over the past years, novel approaches have included targeting EGFR, NTRK, PARP, K-Ras as well as stroma and fibrosis, leading to approval of NTRK and PARP inhibitors. Moreover, immune check point inhibitors and different combinational approaches involving immunotherapeutic agents are being investigated in many clinical trials. MiRNAs represent a novel tool and are thought to greatly improve management by allowing for earlier diagnosis and for more precise guidance of treatment.

Non-pegylated Liposomal Doxorubicin as Palliative Chemotherapy in pre-Treated Advanced Pancreatic Cancer: A Retrospective Analysis of Twenty-Eight Patients.

Background: Pancreatic cancer carries a devastating prognosis and is the fourth leading cause for cancer-related death in the United States and most European countries. Although one-third of patients receive a palliative third line therapy, the benefit of systemic therapy beyond second-line remains unclear. A plethora of clinical trials investigating novel drugs have failed over the past years. Due to the lack of established treatment regimens beyond second line, we offered nonpegylated liposomal doxorubicin, well known in other tumor entities, to pretreated pancreatic cancer patients requesting systemic therapy. Material and Methods: In this retrospective analysis, 28 patients with pancreatic carcinoma treated with nonpegylated liposomal doxorubicin (Myocet®) between 2012 and 2018 at our department were included. Results: For the majority of patients (n = 18, 64%), nonpeglyted liposomal doxorubicin was offered as a third-line therapy. Five patients received it as second line, four patients as fourth line, and one patient as fifth line of therapy. Half of the patients received at least a therapy cycle. The objective response rate to treatment was 7.1%. One patient had a period of radiologically confirmed stable disease with stable tumor markers. Another patient experienced partial remission. Conclusion: According to our findings the benefit of nonpegylated liposomal doxorubicin in pancreatic cancer beyond second line is limited.

Benefit of second-line therapy for advanced esophageal squamous cell carcinoma: a tri-center propensity score analysis.

BACKGROUND: The level of evidence for palliative second-line therapy in advanced esophageal squamous cell carcinoma (aESCC) is limited. This is the first study that reports efficacy data comparing second-line therapy + active symptom control (ASC) versus ASC alone in aESCC. METHODS: We conducted a tri-center retrospective cohort study (n = 166) including patients with aESCC who had experienced disease progression on palliative first-line therapy. A propensity score model using inverse probability of treatment weighting (IPTW) was implemented for comparative efficacy analysis of overall survival (OS) in patients with second-line + ASC (n = 92, 55%) versus ASC alone (n = 74, 45%). RESULTS: The most frequent second-line regimens used were docetaxel (36%) and paclitaxel (18%). In unadjusted primary endpoint analysis, second-line + ASC was associated with significantly longer OS compared with ASC alone [hazard ratio (HR) = 0.49, 95% confidence interval (CI): 0.35-0.69, p < 0.0001]. However, patients in the second-line + ASC group were characterized by more favorable baseline features including a better Eastern Cooperative Oncology Group (ECOG) performance status, a longer first-line treatment duration and lower C-reactive protein levels. After rigorous adjusting for baseline confounders by re-weighting the data with the IPTW the favorable association between second-line and longer OS weakened but prevailed. The median OS was 6.1 months in the second-line + ASC group and 3.2 months in the ASC group, respectively (IPTW-adjusted HR = 0.40, 95% CI: 0.24-0.69, p = 0.001). Importantly, the benefit of second-line was consistent across several clinical subgroups, including patients with ECOG performance status ⩾1 and age ⩾65 years. The most common grade 3 or 4 adverse events associated with palliative second-line therapy were hematological toxicities. CONCLUSION: This real-world study supports the concept that systemic second-line therapy prolongs survival in patients with aESCC.

The Role of Neutrophilic Granulocytes in Philadelphia Chromosome Negative Myeloproliferative Neoplasms.

Philadelphia chromosome negative myeloproliferative neoplasms (MPN) are composed of polycythemia vera (PV), essential thrombocytosis (ET), and primary myelofibrosis (PMF). The clinical picture is determined by constitutional symptoms and complications, including arterial and venous thromboembolic or hemorrhagic events. MPNs are characterized by mutations in JAK2, MPL, or CALR, with additional mutations leading to an expansion of myeloid cell lineages and, in PMF, to marrow fibrosis and cytopenias. Chronic inflammation impacting the initiation and expansion of disease in a major way has been described. Neutrophilic granulocytes play a major role in the pathogenesis of thromboembolic events via the secretion of inflammatory markers, as well as via interaction with thrombocytes and the endothelium. In this review, we discuss the molecular biology underlying myeloproliferative neoplasms and point out the central role of leukocytosis and, specifically, neutrophilic granulocytes in this group of disorders.

Two Cases of Pancytopenia with Coombs-Negative Hemolytic Anemia after Chimeric Antigen Receptor T-Cell Therapy.

BACKGROUND: Chimeric antigen receptor (CAR) T-cells are changing the therapeutic landscape of hematologic malignancies. Severe side effects include cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS), but prolonged cytopenia has also been reported. The underlying mechanism for prolonged cytopenia is poorly understood so far. CASES: Severe pancytopenia with grade 2-3 anemia was marked 2-3 months after treatment. Laboratory evaluation revealed undetectable levels of haptoglobin with increased reticulocyte counts. Coomb's tests were negative, no schistocytes were detected on blood smear, and infectious causes were ruled out. Increased erythropoiesis without lymphoma infiltration was noted on bone marrow biopsy. A spontaneous increase in haptoglobin and hemoglobin levels was observed after several weeks. For one patient, peripheral CAR-T levels were monitored over time. We observed a decline at the same time as hemoglobin levels began to rise, implying a potential causality. CONCLUSION: To our knowledge, we describe the first two cases of Coombs-negative hemolytic anemia after CAR-T treatment for B-cell lymphoma. We encourage routine monitoring for hemolytic anemia after CAR-T treatment and also encourage further investigations on the underlying mechanism.

Prognostic and Predictive Factors in Advanced Head and Neck Squamous Cell Carcinoma.

Head and neck squamous cell carcinoma (HNSCC) is a heterogeneous disease arising from the mucosa of the upper aerodigestive tract. Despite multimodality treatments approximately half of all patients with locally advanced disease relapse and the prognosis of patients with recurrent or metastatic HNSCC is dismal. The introduction of checkpoint inhibitors improved the treatment options for these patients and pembrolizumab alone or in combination with a platinum and fluorouracil is now the standard of care for first-line therapy. However, approximately only one third of unselected patients respond to this combination and the response rate to checkpoint inhibitors alone is even lower. This shows that there is an urgent need to improve prognostication and prediction of treatment benefits in patients with HNSCC. In this review, we summarize the most relevant risk factors in the field and discuss their roles and limitations. The human papilloma virus (HPV) status for patients with oropharyngeal cancer and the combined positive score are the only biomarkers consistently used in clinical routine. Other factors, such as the tumor mutational burden and the immune microenvironment have been highly studied and are promising but need validation in prospective trials.