Search Results (628)

The landscape of first-line treatment for metastatic non-small cell lung cancer (NSCLC) without actionable driver mutations is rapidly evolving, currently dominated by pembrolizumab-based regimens. This review discusses the unique molecular characteristics of cemiplimab, a newer anti-PD-1 antibody, and defines its optimal positioning against established standards. Cemiplimab is a fully human IgG4 monoclonal antibody distinguished by two key features: an engineered hinge-region mutation that prevents Fab-arm exchange, ensuring exceptional molecular stability which minimizes anti-drug antibody (ADA) risks associated with unstable molecules; and a unique interaction with PD-1 glycosylation sites, potentially enhancing binding efficacy. These structural advantages may be particularly relevant in histologies like squamous NSCLC, where accumulating somatic mutations drive high neoantigen loads and heightened immune responses, creating an environment historically prone to ADA formation. Based on data from the pivotal EMPOWER-Lung program, we highlight cemiplimab’s exceptional promise in specific populations. Firstly, in the EMPOWER-Lung 1 trial, cemiplimab monotherapy demonstrated extraordinary survival benefits in a pre-specified analysis of the distinct “ultra-high” PD-L1 expression subgroup (TPS ≥90%), potentially surpassing historical benchmarks. Secondly, cemiplimab displays consistent, robust efficacy in challenging-to-treat squamous histology, both as monotherapy for patients with high PD-L1 expression and in combination with chemotherapy for patients with PD-L1 < 50%. In conclusion, cemiplimab establishes a unique therapeutic niche for patients with squamous histology and ultra-high PD-L1 expression, likely driven by its distinct structural stability and reduced immunogenicity. Full article

Pembrolizumab, an anti-PD-1 monoclonal antibody, showed promising results in the treatment of different types of solid tumors and generally an improvement in overall survival and patients’ outcome. However, as a drug that targets the immune system to enhance the anti-tumor response, it simultaneously increases the risk of autoimmune reactions, producing immune-related adverse events (irAEs). These irAEs might involve any body organ, and in some cases may lead to treatment discontinuation. In this article, we discuss two cases of triple-negative breast cancer (TNBC) patients, who developed irAEs during the course of neoadjuvant pembrolizumab, highlighting the mechanism of the reactions, possible clinical manifestations, and potential management. Full article

Background/Objectives: Non-melanoma skin cancer, which includes cutaneous squamous cell carcinoma (cSCC), ranks as the 5th most common cancer globally with high morbidity and more total deaths than melanoma despite having a lower mortality rate. While most cSCC cases can be treated with surgery, locally advanced, metastatic, and high-risk cSCC tumors are associated with a worse prognosis with higher rates of recurrence and require multimodality therapy. However, there is limited data on animal models of cutaneous squamous cell carcinoma for the use of combinatory immunotherapy and radiation. Methods: In this study, spontaneously generated tumors using DMBA/TPA were treated over three weeks with either IgG control, anti-PD1 antibody monotherapy, 8 Gy of localized radiation, or a combination of anti-PD1 and 8 Gy of radiation followed by anti-PD1 therapy. Results: We found that while anti-PD1 therapy showed a trend toward slowed tumor growth compared to controls, this difference was not statistically significant (p = 0.0775), with most mice showing continued tumor progression. Preliminary histological analysis suggested that anti-PD1 treatment increased CD8+ T cell infiltration, and the addition of radiation further enhanced CD8+ responses but added greater variability. A pathologic review revealed that irradiated tumors were associated with fibroblastic spindle-like cell morphology. Conclusions: This animal model represents a potential preclinical model for studying CSCC with limited responses to immunotherapy to understand potential mechanisms of resistance. Full article

Background/Objectives: Advanced-stage mycosis fungoides (MF) and Sézary syndrome (SS) are aggressive forms of cutaneous T-cell lymphoma (CTCL) for which treatment options are limited and prognosis is poor. Brentuximab vedotin (BV), an anti-CD30 antibody–drug conjugate, has demonstrated high response rates in patients with CD30 expression ≥ 10%. However, data on its efficacy in cases with low CD30 expression (<10%) remain scarce. Methods: This retrospective analysis evaluated the real-world efficacy of BV in patients with advanced-stage MF/SS and low CD30 expression. A retrospective analysis was conducted on 32 patients across 11 German CTCL expert centers. All patients had advanced-stage MF or SS with CD30 expression < 10% and received BV at the standard dose. Treatment response was assessed using EORTC-ISCL criteria. Results: All patients had received prior systemic therapies (median: 3) with 36% having undergone prior mono- or polychemotherapy. The study population included 30 MF (stage IIB) and two SS cases. The overall response rate (ORR) in this population was 53.1% (17/32). A complete response (CR) was achieved in 12.5% (4/32), a partial response (PR) was achieved in 40.6% (13/32), stable disease (SD) was seen in 18.8% (6/32), and progressive disease (PD) was seen in 28.1% (9/32). The median progression-free survival (PFS) was 4.0 months (arithmetic mean: 6.38; range: 0.5–15.5), and the median time to next treatment (TTNT) was 7.25 months (arithmetic mean: 7.30; range: 2.00–15.5). Conclusions: BV demonstrated encouraging activity in heavily pretreated advanced MF/SS with low CD30 expression, achieving an ORR comparable to that observed in patients with higher CD30 levels. While response rates were similar, PFS was shorter. These findings suggest that BV remains a potential therapeutic option in this patient population and merits further prospective investigation. Full article

Background/Objectives: The anti-PD-L1 antibody has been applied for use in first-line advanced biliary duct cancer patients. However, clinical evidence of toripalimab in combination with biweekly 5-fluorouracil (5-FU) is limited and predictive biomarkers of treatment benefits remain unclear. Methods: This prospective study enrolled patients with unresectable or metastatic BTC who received toripalimab in combination with gemcitabine and biweekly 5-FU. The primary endpoints were progression-free survival (PFS) and objective response rate (ORR). Secondary endpoints included overall survival (OS) and safety. Exploratory analyses evaluated associations between programmed cell death-ligand 1 (PD-L1) expression or tumor mutational burden (TMB) and clinical outcomes. Results: A total of 30 patients were enrolled, with a median follow-up duration of 16.0 months. The ORR was 13.0%. The median PFS and OS were 5.3 months (95% CI: 3.59–7.01) and 11.7 months (95% CI: 6.07–17.33), respectively. Subgroup analyses revealed no significant association between PD-L1 status or TMB level and improved PFS. All patients experienced adverse events (AEs), while grade 3–4 AEs occurred in eight patients (26.7%), most commonly anemia (20.0%), leukocytopenia (13.3%), and nausea (6.6%). No grade 5 AEs were observed, and the safety profile was considered manageable. Conclusions: Toripalimab in combination with gemcitabine and 5-fluorouracil showed promising efficacy and was well-tolerated as a first-line therapy in advanced biliary duct cancer patients. Although PD-L1 expression and TMB did not predict treatment benefit, larger studies are needed to validate potential biomarkers and further optimize immunochemotherapy strategies for BTC. Full article

Background: Electrochemotherapy (ECT) is a clinically validated local ablative treatment increasingly recognized for its ability to induce immunogenic cell death and stimulate antitumor immunity. Its combination with immune checkpoint inhibitors, such as anti-PD-1 antibodies, may enhance systemic immune responses and improve therapeutic efficacy, particularly in poorly immunogenic tumors. Methods: We evaluated the antitumor effectiveness of ECT combined with a murine analog of the anti-PD-1 antibody in four syngeneic murine tumor models with differing histology and immune status: WEHI fibrosarcoma, CT26 and MC38 colorectal carcinoma, and 4T1 mammary carcinoma. In vitro cytotoxicity assays assessed tumor cell sensitivity to ECT, while in vivo experiments evaluated complete response (CR) rates, immune cell infiltration, and long-term immune memory through secondary tumor challenge. Immunohistochemical analysis of CD4⁺, CD8⁺, and granzyme B⁺ effector cells. Results: In vitro, WEHI cells exhibited the highest sensitivity to ECT. In vivo, ECT monotherapy induced CRs in 100% of WEHI tumors, 60% of CT26, 17% of 4T1, and 15% of MC38. The addition of anti-PD-1 significantly enhanced outcomes in less responsive models, increasing CRs to 90% in CT26, 91% in MC38, and 53% in 4T1. Combination therapy promoted pronounced infiltration of CD4⁺, CD8⁺, and granzyme B⁺ T cells and the formation of tertiary lymphoid structure, particularly in MC38 tumors. Secondary challenge experiments confirmed long-term immune memory in CT26 and MC38 models and induced memory in 4T1, which was absent following monotherapy. Conclusions: ECT synergizes with PD-1 blockade to potentiate local and systemic antitumor immunity, overcoming immune resistance in poorly immunogenic tumors. These findings support further clinical development of ECT in combination with immune checkpoint inhibitors as a component of personalized cancer immunotherapy. Full article

Purpose: The objective of this study was to evaluate the synergistic effect of combining an immune checkpoint inhibitor (ICI) with radiotherapy (RT) on murine fibrosarcoma and to conduct a narrative review of clinical studies on soft tissue sarcoma (STS). Materials and Methods: Forty male C3H mice (aged 5 weeks) were injected intramuscularly with 2 × 10⁵ FSaII cells into the right thigh and randomly assigned to four groups: (1) control; (2) RT; (3) InVivoMab™ (CD279) (mouse anti-PD-1 antibody) (ICI group); and (4) combined treatment with InVivoMab™ (CD279) and RT (combination group). On day −1, ICI was administered intraperitoneally. On day 0, RT (10 Gy, single fraction) was delivered locally to the tumors in the right hind limb. Subsequently, ICI was injected twice weekly (a total of 8 times). On day 26, all mice were euthanized, and the results were analyzed. In addition, a narrative review was conducted to identify clinical evidence. Results: On day 26, mean gross tumor volumes were 3578.13 ± 407.32 mm³ in the control group, 1995.72 ± 970.46 mm³ in the RT group, 2729.96 ± 286.47 mm³ in the ICI group, and 1007.92 ± 197.36 mm³ in the combination group. Gross tumor growth delay was most pronounced in the combination group. Moreover, the TUNEL assay demonstrated a significant increase in apoptosis in the combination group. Analysis of the underlying immune system revealed significantly higher expression of CD4+, CD8+, and IFN-γ in the combination group. The literature search identified only 12 case reports and 3 prospective studies involving patients with STS treated with the combined treatment of ICI and RT, suggesting potential synergism with acceptable toxicity. Conclusions: The current study demonstrated a synergistic effect of combining an ICI with RT in murine fibrosarcoma. There was limited data in the clinical setting. Further investigations are warranted to determine the optimal combination strategy of ICI and RT for STS. Full article

Background/Objectives: Notwithstanding the declaration by the World Health Organization in May 2023 regarding the conclusion of the COVID-19 pandemic, new cases of this potentially lethal infection continue to be documented globally, exerting a sustained influence on the worldwide economy and social structures. Contemporary SARS-CoV-2 variants, while associated with a reduced propensity for severe acute pathology, retain the capacity to induce long-term post-COVID syndrome, including in ambulatory patient populations. This clinical phenomenon may be attributable to potential autoimmune reactions hypothetically triggered by antiviral antibodies, thereby underscoring the need for developing novel, universal vaccines against COVID-19. The nucleocapsid protein (N), being one of its most conserved and highly immunogenic components of SARS-CoV-2, presents a promising target for such investigative efforts. However, the protective role of anti-N antibodies, generated during natural infection or through immunization with N-based vaccines, alongside the potential adverse effects associated with their production, remains to be fully elucidated. In the present study, we aim to identify potential sites of homology in structures or sequences between the SARS-CoV-2 N protein and human antigens detected using hyperimmune sera against N protein obtained from mice, rabbits, and hamsters. Methods: We employed Western blot analysis of lysates from human cell lines (MCF7, HEK293T, THP-1, CaCo2, Hep2, T98G, A549) coupled with mass spectrometric identification to assess the cross-reactivity of polyclonal and monoclonal antibodies generated against recombinant SARS-CoV-2 N protein with human self-antigens. Results: We showed that anti-N antibodies developed in mice and rabbits exhibit pronounced immunoreactivity towards specific components of the human proteome. In contrast, anti-N immunoglobulins from hamsters showed no non-specific cross-reactivity with either hamster or human proteomic extracts because of the lack of autoreactivity or immunogenicity differences. Subsequent mass spectrometric analysis of the immunoreactive bands identified principal autoantigenic targets, which were predominantly heat shock proteins (including HSP90-beta, HSP70, mitochondrial HSP60, and HSPA8), histones (H2B, H3.1–3), and key metabolic enzymes (G6PD, GP3, PKM, members of the 1st family of aldo-keto reductases). Conclusions: The results obtained herein highlight the differences in the development of anti-N humoral responses in humans and in the Syrian hamster model. These data provide a foundational basis for formulating clinical recommendations to predict possible autoimmune consequences in COVID-19 convalescents and are of critical importance for the rational design of future N protein-based, cross-protective vaccine candidates against novel coronavirus infections. Full article

The therapeutic clotting factor VIII (FVIII) is known for its particular immunogenicity, with nearly 30% of hemophilic patients developing neutralizing antibodies against the infused protein. The root cause of this immunogenicity is still not well understood, but intrinsic factors, such as FVIII byproducts, have been linked to the immunological response elicited. Bioengineering of the FVIII molecule has been improving its recombinant (rhFVIII) production in many aspects, mainly enhancing its expression and stability. Assessment of immunogenicity for novel recombinant isoforms is crucial for further development and scaling-up processes, particularly due to the unpredictable antigenic properties and their impact on neutralizing antibody formation. In the present study, we describe a bioengineered human recombinant FVIII (rhFVIII-H6A), which induces lower immunogenicity in a murine model of hemophilia A. The rhFVIII-H6A product is characterized by a B-domain-deleted heavy chain (HCh), with the C-terminal of the B-domain fused to the light chain (BΔ-LCh). Compared to plasma-derived FVIII (pdFVIII) and rhFVIII reference products, treating hemophilic mice with rhFVIII-H6A induced lower levels of anti-FVIII antibody formation, including those with inhibitory neutralizing activity, while no difference was observed in the functional activity of rhFVIII-H6A in reverting the in vivo hemophilia phenotype. In addition, our results indicate that deleting the major part of the B-domain from the HCh might lower the immunogenicity of novel rhFVIII products. Full article

The limited efficacy of cytotoxic chemotherapy in the context of gastric cancer treatment is largely driven by profound molecular and biological heterogeneity. In contrast, the development of antibody-mediated therapies has ushered in a new era of precision oncology by enabling selective molecular targeting and immune modulation. This review includes a comprehensive overview of the evolution of antibody-based therapeutics in gastric cancer, highlighting early breakthroughs, subsequent setbacks, and recent advances that have reshaped the treatment landscape. We summarize the current standard regimens targeting HER2, VEGFR2, PD-1/PD-L1, and CLDN18.2 and examine pivotal clinical trials evaluating monoclonal antibodies directed against these pathways. We also discuss emerging therapeutic modalities, including next-generation antibody–drug conjugates (ADCs), bispecific antibodies, and chimeric antigen receptor (CAR) T-cell therapies. Trastuzumab first established HER2-targeted therapy in gastric cancer, but the failure of trastuzumab emtansine (T-DM1) led to a decade-long stagnation until the advent of trastuzumab deruxtecan (T-DXd), which demonstrated robust clinical activity and defined a new standard of care. While bevacizumab failed to improve survival, the anti-VEGFR2 antibody ramucirumab emerged as an effective second-line therapy. Immune checkpoint inhibitors, including nivolumab and pembrolizumab, have been incorporated into first-line treatment for PD-L1-positive disease based on landmark trials such as CheckMate 649 and KEYNOTE-811. More recently, the CLDN18.2-targeted antibody zolbetuximab has expanded therapeutic options for biomarker-selected patients. Concurrently, a diverse pipeline of immune-based strategies—such as TROP2-directed ADCs, bispecific antibodies, and CAR-T cell therapies—is undergoing active clinical development. Together, advances in biomarker-driven antibody therapeutics are accelerating personalized cancer care and improving clinical outcomes in patients with gastric cancer. Full article

Radiopharmaceutical therapy (RPT) offers tumor-selective radiation delivery and represents a promising platform for combination with immune checkpoint inhibitors (ICIs). While prior studies suggest that RPT can stimulate antitumor immunity, synergy with ICIs may depend on radionuclide properties, absorbed dose, and radiation distribution within the tumor microenvironment. This study evaluated how radionuclide selection and dose influence immune stimulation and therapeutic efficacy of GD2-targeted antibody-based RPT combined with ICIs. Dinutuximab, an anti-GD2 monoclonal antibody, was radiolabeled with β⁻-emitters (⁹⁰Y, ¹⁷⁷Lu) or an α-emitter (²²⁵Ac). C57Bl6 mice bearing GD2⁺ tumors received 4 or 15 Gy tumor-absorbed doses, determined by individualized dosimetry, with or without dual ICIs (anti-CTLA-4 and anti-PD-L1). In vivo imaging, ex vivo biodistribution, survival, histological, and gene expression analyses were performed to assess therapeutic and immunological outcomes. All radiolabeled constructs demonstrated preferential uptake in GD2⁺ tumors. Combination therapy improved survival in a radionuclide- and dose-dependent manner, with the greatest benefit in the ²²⁵Ac + ICI group at 15 Gy. Treatment activated type I interferon signaling and increased MHC-I and PD-L1 expression. Notably, ⁹⁰Y reduced regulatory T cells, enhancing CD8⁺/Treg ratios, while ²²⁵Ac induced robust interferon-driven activation. Radionuclide selection and absorbed dose critically shape immune and therapeutic outcomes of antibody-based RPT combined with ICIs, underscoring the importance of delivery mechanism and dose optimization in combination therapy strategies. Full article

Background/Objectives: Melanoma is a highly malignant skin tumor with poor response to conventional chemotherapeutic regimens. Melanoma cells induce cytotoxic T cell-mediated immune responses, and immunotherapy has significantly improved survival rates for patients with advanced disease. Methods: Here, we investigate NK cell-mediated melanoma cell killing and its regulation by PD-L1/PD-1 blockade and IFNβ. Four melanoma cell lines were used in this study. To evaluate NK cell cytotoxicity, cells were exposed to NK cells with or without IFNβ. The calcein release assay was used to measure cell death, while specific inhibitors and siRNA silencing were applied to determine the contribution of individual effector pathways. Results: NK cells were able to kill melanoma cells with sensitivity to killing varying between different cell lines. Cytotoxic effects were mainly mediated through activation of the TRAIL signaling cascade. In cell lines with low sensitivity to NK cell killing, expression of PD-L1 was noted and killing by NK cells could be significantly increased by inhibition of the PD-L1/PD-1 checkpoint. Killing of melanoma cells could be further increased by incubation of NK cells with IFNβ. Conclusions: Our results point to a role of NK cells in the killing of melanoma cells and a potential clinical benefit of a combination therapy of IFNβ and anti-PD-1 antibody. Full article

L1 cell adhesion molecule (L1CAM)-positive extracellular vesicles (EVs) are being explored as a potential source of biomarkers for Parkinson’s disease (PD) in peripheral blood. However, their utility remains controversial. In this study, we sought to investigate the proteome composition of L1CAM⁺-EVs isolated from human blood plasma and evaluate their potential as biomarkers for PD. L1CAM⁺-EVs were extracted from blood plasma using direct immunoprecipitation by employing magnetic beads coupled to an anti-L1CAM antibody. The Proximity Extension Assay platform, Olink Explore 3072, was used to analyze samples from 60 individuals: 20 healthy controls (HC), 20 patients with isolated REM sleep behavior disorder (iRBD), and 20 PD patients. Targeted proteomic analysis identified 2841 proteins in L1CAM⁺-EVs, of which 203 exhibited differential expression across groups. Although these changes were not statistically significant, after correction for multiple testing, a combination of 12 proteins could discriminate between PD and HC. Moreover, several proteins displayed trends toward upregulation or downregulation in PD and iRBD when compared with HC. These preliminary findings suggest that L1CAM⁺-EVs proteins show some potential as biomarkers for PD; however, further investigation and validation studies are required. Full article

Chimeric antigen receptor (CAR) T cell therapy for B cell malignancies is often limited by T cell exhaustion, which is frequently driven by the PD-1/PD-L1 immune checkpoint axis. To overcome this, we developed an “armored” CAR-T cell strategy using a novel bidirectional promoter system. We engineered a single vector to co-express a CD19-specific CAR alongside a secreted anti-PD1 molecule, in either a full-length antibody or a single-chain variable fragment (scFv) format, using the Sleeping Beauty (SB) transposon system. The sequences for the anti-PD1 modules were derived from the clinical antibody nivolumab. Both armored constructs demonstrated robust CAR expression, comparable to or higher than conventional CAR-T cells, and proliferated significantly more than untransfected controls. The engineered cells successfully secreted their anti-PD1 payloads, with the full-length antibody showing more sustained secretion than the scFv. This autocrine blockade resulted in significantly reduced surface PD1 expression on the armored CAR-T cells. Functionally, the anti-PD1-secreting cells exhibited superior cytotoxicity against PD-L1-positive Raji target cells, particularly at low effector-to-target ratios. Critically, in a serial rechallenge assay designed to simulate chronic antigen exposure, both armored CAR-T cell groups showed markedly enhanced proliferation and persistence compared to conventional CAR-T cells, which failed to expand after repeated stimulation. Our findings validate the bidirectional EF1 promoter as an efficient system for generating multi-functional T cells and demonstrate that armoring CAR-T cells with secreted anti-PD1 antibodies is a potent strategy to enhance their persistence and anti-tumor efficacy. Full article

Rapid advancements in understanding how the immune system can eliminate tumors have quickly translated into breakthroughs in developing cancer therapeutics. Immune checkpoint inhibitors (ICIs) have shown great promise in several cancers; however, resistance can affect up to two-thirds of patients receiving ICIs. A significant limitation of the effectiveness of anti-PD-1 therapy centers around the insufficient levels of immune cells needed to recognize and kill cancer cells compared to the number of suppressive immune cells within the tumor microenvironment. Determining what is required to overcome the resistance to anti-PD-1 therapy in breast cancer remains a critical need. Our data demonstrate that IL-15 complexes injected intratumorally in combination with PD-1 blockade therapy induce regression of established luminal B mammary breast tumors. We show that IL-15 alone or in combination with anti-PD-1 drives changes in gene expression of pathways associated with TCR and co-stimulatory signaling, immune cell adhesion, and migration. Furthermore, we show that intratumoral injection of IL-15 complexes traffics to the tumor-draining lymph node, as evidenced by Light sheet microscopy, and colocalizes with the anti-PD-1 monoclonal antibody. We also identify the immune signatures, localization, and distribution of immune cells in regressing and non-regressing breast tumors. Full article