A Phase I/IIa Randomized Trial Evaluating the Safety and Efficacy of SNK01 Plus Pembrolizumab in Patients with Stage IV Non-Small Cell Lung Cancer

Next-generation immunotherapy: igniting new hope for lung cancer

Adoption of immunotherapy has completely transformed the treatment landscape of cancer. Patients with advanced cancer treated with immunotherapy may benefit from durable tumor response and long-term survival. The most widely used immunotherapy in solid tumors is anti-programmed-death (ligand) protein (PD-(L)1), which is now an integral part of non-small cell lung cancer (NSCLC) treatment irrespective of histological cell types and tumor stage. However, the vast majority of patients with advanced NSCLC treated with anti-PD-(L)1 still develop therapeutic resistance, and the prognosis after anti-PD-(L)1 resistance is poor. Resistance mechanisms to PD-1 blockade are often complex and encompass a combination of defects within the cancer-immunity cycle. These defects include failure in antigen presentation and T-cell priming, presence of co-inhibitory immune checkpoints, inability of immune cells to infiltrate the tumor, and presence of immunosuppressive tumor microenvironment. Recently, advances in drug design, genomic sequencing, and gene editing technologies have led to development of next-generation immunotherapies that may potentially overcome these resistance mechanisms. In this review, we will discuss the anti-PD-(L)1 resistance mechanism landscape in NSCLC and four novel modalities of immunotherapy in detail, namely novel immune checkpoint inhibitor and targeted therapy combinations, bispecific antibodies, cancer vaccine, and cell therapy. These novel therapeutics have all demonstrated early clinical data in NSCLC treatment and may work synergistically with each other to restore anticancer immunity. In addition, we share our perspectives on the future promises and challenges in the transformation of these novel immunotherapies to standard clinical care.

Efficacy and safety of natural killer cell therapy in patients with solid tumors: a systematic review and meta-analysis

Introduction

In 2020, global cancer statistics reported 19.3 million new cases and 10 million deaths annually, highlighting the urgent need for effective treatments. Current therapies, such as surgery, radiation, and chemotherapy, have limitations in comprehensively addressing solid tumor. Recent advances in cancer biology and immuno-oncology, including CAR-T cell therapy, show promise but face efficacy challenges against solid tumors.

Methods

This meta-analysis systematically reviewed studies from PubMed, Embase, Cochrane, and ClinicalTrials.gov databases up to May 2024 to evaluate the clinical efficacy and safety of unmodified NK cell therapies in solid tumors. The included trials focused on reporting objective response rates (ORR).

Results

Thirty-one trials involving 600 patients across various cancers (e.g., NSCLC, HCC, breast, ovarian) were analyzed. NK cell therapies demonstrated promising ORRs, particularly 72.3% in hepatocellular carcinoma, often in combination with local therapies. Safety profiles were favorable, with fatigue being the most common adverse event.

Discussion

NK cell therapies represent a promising treatment option for solid tumors, offering a viable alternative to genetically modified cell therapies like CAR-T. Further research is needed to optimize the clinical utility of NK cell therapy and integrate it effectively into standard cancer treatment regimens.

Systematic review registration

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023438410, identifier CRD42023438410.

Disruption of TGF-β signaling pathway is required to mediate effective killing of hepatocellular carcinoma by human iPSC-derived NK cells

Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer. Transforming growth factor beta (TGF-β) is highly expressed in the liver tumor microenvironment and is known to inhibit immune cell activity. Here, we used human induced pluripotent stem cells (iPSCs) to produce natural killer (NK) cells engineered to mediate improved anti-HCC activity. Specifically, we produced iPSC-NK cells with either knockout TGF-β receptor 2 (TGFBR2-KO) or expression of a dominant negative (DN) form of the TGF-β receptor 2 (TGFBR2-DN) combined with chimeric antigen receptors (CARs) that target either GPC3 or AFP. The TGFBR2-KO and TGFBR2-DN iPSC-NK cells are resistant to TGF-β inhibition and improved anti-HCC activity. However, expression of anti-HCC CARs on iPSC-NK cells did not lead to effective anti-HCC activity unless there was also inhibition of TGF-β activity. Our findings demonstrate that TGF-β signaling blockade is required for effective NK cell function against HCC and potentially other malignancies that express high levels of TGF-β.

Strategies to enhance the therapeutic efficacy of anti-PD-1 antibody, anti-PD-L1 antibody and anti-CTLA-4 antibody in cancer therapy

Although immune checkpoint inhibitors (anti-PD-1 antibody, anti-PD-L1 antibody, and anti-CTLA-4 antibody) have displayed considerable success in the treatment of malignant tumors, the therapeutic effect is still unsatisfactory for a portion of patients. Therefore, it is imperative to develop strategies to enhance the effect of these ICIs. Increasing evidence strongly suggests that the key to this issue is to transform the tumor immune microenvironment from a state of no or low immune infiltration to a state of high immune infiltration and enhance the tumor cell-killing effect of T cells. Therefore, some combination strategies have been proposed and this review appraise a summary of 39 strategies aiming at enhancing the effectiveness of ICIs, which comprise combining 10 clinical approaches and 29 foundational research strategies. Moreover, this review improves the comprehensive understanding of combination therapy with ICIs and inspires novel ideas for tumor immunotherapy.

Epigenetic regulation of NKG2D ligand and the rise of NK cell-based immunotherapy for cancer treatment

Epigenetic modifications influence gene expression and effects cancer initiation and progression. Therefore, they serve as diagnostic and prognostic biomarkers and potential therapeutic targets. Natural Killer (NK) cells, integral to the innate immune system, exhibit anti-tumor effect by recognizing and eliminating cancerous cells through the balance of activating and inhibitory ligands. Understanding the epigenetic regulation of NK cell ligands offers insights into enhancing NK cell-mediated tumor eradication. This review explores the epigenetic modifications governing the expression of activating NKG2D ligands and discusses clinical trials investigating NK cell-based immunotherapies, highlighting their potential as effective cancer treatment strategies. Case studies examining the safety and effectiveness of NK cell therapies in different cancer types, such as acute myeloid leukemia (AML) and non-small cell lung cancer (NSCLC), demonstrate promising outcomes with minimal toxicity. These findings underscore the therapeutic prospects of epigenetic modulation of NKG2D ligands and NK cell-based immunotherapies as effective cancer treatment strategies. Future research in the advancement of personalized medicine approaches and novel combination therapies with NK cell will further improve treatment outcomes and provide new therapeutic options for treating patients with various types of cancer.

Safety and efficacy of SNK01 (autologous natural killer cells) in combination with cytotoxic chemotherapy and/or cetuximab after failure of prior tyrosine kinase inhibitor in non-small cell lung cancer: non-clinical mouse model and phase I/IIa clinical study

BACKGROUND

Choosing treatments for epidermal growth factor receptor (EGFR)-mutated non-small cell lung cancer (NSCLC) patients with osimertinib resistance is challenging. We evaluated the safety and efficacy of SNK01 (autologous natural killer (NK) cells) in combination with cytotoxic chemotherapy and/or cetuximab (an anti-EGFR monoclonal antibody) in treating EGFR-mutated NSCLC in this non-clinical and phase I/IIa clinical trial.

METHODS

We developed a cell line-derived xenograft-humanized mouse model with an osimertinib-resistant lung cancer cell line. The mice were divided into four groups based on treatment (no treatment, cetuximab, SNK01, and combination groups) and treated weekly for 5 weeks. In the clinical study, 12 patients with EGFR-mutated NSCLC who failed prior tyrosine kinase inhibitor (TKI) received SNK01 weekly in combination with gemcitabine/carboplatin (n=6) or cetuximab/gemcitabine/carboplatin (n=6) and dose escalation of SNK01 following the "3+3" design.

RESULTS

In the non-clinical study, an increase in NK cells in the blood and enhanced NK cell tumor infiltration were observed in the SNK01 group. The volume of tumor extracted after treatment was the smallest in the combination group. In the clinical study, 12 patients (median age, 60.9 years; all adenocarcinoma cases) received SNK01 weekly for 7-8 weeks (4×109 cells/dose (n=6); 6×109 cells/dose (n=6)). The maximum feasible dose of SNK01 was 6×109 cells/dose without dose-limiting toxicity. Efficacy outcomes showed an objective response rate of 25%, disease control rate of 100%, and median progression-free survival of 143 days.

CONCLUSION

SNK01 in combination with cytotoxic chemotherapy, including cetuximab, for EGFR-mutated NSCLC with TKI resistance was safe and exerted a potential antitumor effect.

TRIAL REGISTRATION NUMBER

NCT04872634.

Harnessing Natural Killer Cells for Lung Cancer Therapy

Lung cancer is the leading cause of cancer-related death worldwide. Although natural killer (NK) cells are garnering interest as a potential anticancer therapy because they selectively recognize and eliminate cancer cells, their use in treating solid tumors, including lung cancer, has been limited due to impediments to their efficacy, such as their limited ability to reach tumor tissues, the reduced antitumor activity of tumor-infiltrating NK cells, and the suppressive tumor microenvironment (TME). This comprehensive review provides an in-depth analysis of the cross-talk between the lung cancer TME and NK cells. We highlight the various mechanisms used by the TME to modulate NK-cell phenotypes and limit infiltration, explore the role of the TME in limiting the antitumor activity of NK cells, and discuss the current challenges and obstacles that hinder the success of NK-cell-based immunotherapy for lung cancer. Potential opportunities and promising strategies to address these challenges have been implemented or are being developed to optimize NK-cell-based immunotherapy for lung cancer. Through critical evaluation of existing literature and emerging trends, this review provides a comprehensive outlook on the future of NK-cell-based immunotherapy for treating lung cancer.

Cellular Therapy in NSCLC: Between Myth and Reality

PURPOSE OF REVIEW

In this paper, we review the current state and modalities of adoptive cell therapies (ACT) in non-small cell lung carcinoma (NSCLC). We also discuss the challenges hampering the use of ACT and the approaches to overcome these barriers.

RECENT FINDINGS

Several trials are ongoing investigating the three main modalities of T cell-based ACT: tumor-infiltrating lymphocytes (TILs), genetically engineered T-cell receptors (TCRs), and chimeric antigen receptor (CAR) T cells. The latter, in particular, has revolutionized the treatment of hematologic malignancies. However, the efficacy against solid tumor is still sparse. Major limitations include the following: severe toxicities, restricted infiltration and activation within the tumors, antigen escape and heterogeneity, and manufacturing issues. ACT is a promising tool to improve the outcome of metastatic NSCLC, but significant translational and clinical research is needed to improve its application and expand the use in NSCLC.

NK cell activity and methylated HOXA9 ctDNA as prognostic biomarkers in patients with non-small cell lung cancer treated with PD-1/PD-L1 inhibitors

BACKGROUND

PD-1/PD-L1 inhibitors have improved survival for patients with non-small cell lung cancer (NSCLC). We evaluated natural killer cell activity (NKA) and methylated HOXA9 circulating tumor DNA (ctDNA) as prognostic biomarkers in NSCLC patients treated with PD-1/PD-L1 inhibitors.

METHODS

Plasma was prospectively collected from 71 NSCLC patients before treatment with PD-1/PD-L1 inhibitors and before cycles 2-4. We used the NK Vue® assay to measure the level of interferon gamma (IFNγ) as a surrogate for NKA. Methylated HOXA9 was measured by droplet digital PCR.

RESULTS

A score combining NKA and ctDNA status measured after one treatment cycle had a strong prognostic impact. Group 1 had IFNγ < 250 pg/ml and detectable ctDNA (n = 27), group 2 consisted of patients with either low levels of IFNγ and undetectable ctDNA or high levels of IFNγ and detectable ctDNA (n = 29), group 3 had IFNγ ≥250 pg/ml and undetectable ctDNA (n = 15). Median OS was 221 days (95% CI 121-539 days), 419 days (95% CI 235-650 days), and 1158 days (95% CI 250 days-not reached), respectively (P = 0.002). Group 1 had a poor prognosis with a hazard ratio of 5.560 (95% CI 2.359-13.101, n = 71, P < 0.001) adjusting for PD-L1 status, histology, and performance status.

CONCLUSIONS

Combining NKA and ctDNA status after one cycle of treatment was prognostic in patients with NSCLC treated with PD-1/PD-L1 inhibitors.

Natural killer cells: the next wave in cancer immunotherapy

Immunotherapies focusing on rejuvenating T cell activities, like PD-1/PD-L1 and CTLA-4 blockade, have unprecedentedly revolutionized the landscape of cancer treatment. Yet a previously underexplored component of the immune system - natural killer (NK) cell, is coming to the forefront of immunotherapeutic attempts. In this review, we discuss the contributions of NK cells in the success of current immunotherapies, provide an overview of the current preclinical and clinical strategies at harnessing NK cells for cancer treatment, and highlight that NK cell-mediated therapies emerge as a major target in the next wave of cancer immunotherapy.