Immune correlates with response in patients with metastatic solid tumors treated with a tumor targeting immunocytokine NHS-IL12

Combination of HDAC inhibition and cytokine enhances therapeutic HPV vaccine therapy

BACKGROUND

Human papillomavirus (HPV)-associated malignancies continue to present a major health concern despite the development of prophylactic vaccines. Standard therapies offer limited benefit to patients with advanced-stage disease. Despite improved outcomes with programmed cell death protein-1 (PD-1) targeted therapies, treatment resistance and modest response rates highlight a significant unmet need to develop novel therapies for these patients. PDS0101 (designated HPV vaccine) is a liposomal nanoparticle HPV16-specific therapeutic vaccine that has been shown to generate strong HPV-specific responses in preclinical and clinical studies. Here we assess the efficacy of this HPV vaccine in combination with the tumor-targeting immunocytokine NHS-IL12 (PDS01ADC), plus either αPD-1 or the class I histone deacetylase inhibitor Entinostat.

METHODS

Mice bearing HPV16+, αPD-1 refractory TC-1 and mEER tumors were treated with HPV vaccine, NHS-IL12, and either αPD-1 or Entinostat to determine antitumor efficacy and survival benefits. A comprehensive analysis of the tumor microenvironment was performed using flow cytometry, multiplex immunofluorescence, chemokine and cytokine assessment, and single-cell RNA sequencing with T-cell receptor (TCR) enrichment.

RESULTS

Combination of HPV vaccine and NHS-IL12 with either Entinostat or αPD-1 yielded significant antitumor activity and prolonged survival in αPD-1 refractory models of HPV16+ cancer, with superior activity employing Entinostat versus αPD-1 combination. Entinostat triple therapy increased overall and HPV16-specific tumor CD8+ T-cell infiltration with heightened cytotoxicity. TCR sequencing revealed a CD8+ T-cell clone unique to vaccine-treated cohorts, which displayed an enriched cytotoxic transcriptional profile with triple therapy. These effects were paralleled by strong differentiation of tumor-associated macrophages (TAMs) towards pro-inflammatory, antitumor M1-like cell states. Single-cell transcriptomic analysis indicated all three agents were required for highest modulation of both CD8+ T cells and TAMs conducive to tumor control. A biomarker signature reflecting the preclinical findings was found to be associated with improved survival in patients with HPV-associated malignancies.

CONCLUSION

Together, these findings provide a rationale for the combination of HPV vaccine, NHS-IL12, and Entinostat in the clinical setting for patients with HPV16-associated malignancies.

Cytokine-mediated regulation of immune cell metabolic pathways in the tumor microenvironment

Cancer, an important global health problem, is defined by aberrant cell proliferation and continues to be the main cause of death globally. The tumor microenvironment (TME) plays an essential role in the development of cancer, resistance to therapy, and regulation of the immune response. Some immune cells in the TME, like T cells, B cells, macrophages, dendritic cells, and natural killer cells, can either stop or help tumor growth, depending on how metabolic and cytokine changes happen. Cytokines function as essential signaling molecules that modulate immune cell metabolism, altering their functionality. This review focuses on how cytokine-mediated metabolic reprogramming affects the activity of immune cells inside the TME, which can either make the immune response stronger or weaker. New ways of treating cancer that focus on metabolic pathways and cytokine signaling, such as using IL (Interleukin) - 15, IL- 10, and IL- 4, show promise in boosting immune cell activity and making cancer treatments more effective. Finding these pathways could lead to new ways to treat cancer with immunotherapy that focus on metabolic competition and immune resistance in the TME.

IL-12-producing cytokine factories induce precursor exhausted T cells and elimination of primary and metastatic tumors

BACKGROUND

Curative responses to immunotherapy require the generation of robust systemic immunity with limited toxicity. Recruitment of T cell populations such as precursor exhausted T cells (Tpex) from lymphoid tissues to tumors is a hallmark of effective treatment. However, the ability to efficiently induce this recruitment is lacking in current immunotherapy approaches. Furthermore, systemic administration of immunotherapies frequently results in dose-limiting toxicities, yielding an inadequate therapeutic window for eliciting durable responses.

METHODS

In this investigation, we evaluated the safety and antitumor efficacy of locally administered interleukin 12 (IL-12) using a clinically translatable cytokine delivery platform (NCT05538624) to identify Tpex recruitment capabilities at tolerable cytokine doses.

RESULTS

We show IL-12 cytokine factories can effectively treat a broad spectrum of cancer types. Single-cell RNA sequencing data suggests that the antitumor efficacy seen in our studies was due to retinal pigmented epithelial cells-mIL12 treatment inducing differentiation of Tpex cells within the tumor microenvironment. When administered in combination with checkpoint therapy, IL-12 cytokine factory treatment generated systemic abscopal immunity, preventing subcutaneous tumor outgrowth in 8/9 mice with colorectal cancer and lung metastasis in mice with melanoma. Furthermore, this platform was well tolerated in a non-human primate without signs of toxicity.

CONCLUSIONS

Our new immunotherapy approach provides a robust strategy for inducing Tpex recruitment and systemic immunity against a range of solid peritoneal malignancies, many incurable with current immunotherapy strategies. Notably, these features were achieved using IL-12, and by leveraging our technology, we avoided the toxicities that have prevented the translation of IL-12 to the clinic. Our findings provide a strong rationale for the clinical development of IL-12 cytokine factories.

Efficacy of Anti-Cancer Immune Responses Elicited Using Tumor-Targeted IL-2 Cytokine and Its Derivatives in Combined Preclinical Therapies

Effective cancer therapies must address the tumor microenvironment (TME), a complex network of tumor cells and stromal components, including endothelial, immune, and mesenchymal cells. Durable outcomes require targeting both tumor cells and the TME while minimizing systemic toxicity. Interleukin-2 (IL-2)-based therapies have shown efficacy in cancers such as metastatic melanoma and renal cell carcinoma but are limited by severe side effects. Innovative IL-2-based immunotherapeutic approaches include immunotoxins, such as antibody-drug conjugates, immunocytokines, and antibody-cytokine fusion proteins that enhance tumor-specific delivery. These strategies activate cytotoxic CD8+ T lymphocytes and natural killer (NK) cells, eliciting a potent Th1-mediated anti-tumor response. Modified IL-2 variants with reduced Treg cell activity further improve specificity and reduce immunosuppression. Additionally, IL-2 conjugates with peptides or anti-angiogenic agents offer improved therapeutic profiles. Combining IL-2-based therapies with immune checkpoint inhibitors (ICIs), anti-angiogenic agents, or radiotherapy has demonstrated synergistic potential. Preclinical and clinical studies highlight reduced toxicity and enhanced anti-tumor efficacy, overcoming TME-driven immune suppression. These approaches mitigate the limitations of high-dose soluble IL-2 therapy, promoting immune activation and minimizing adverse effects. This review critically explores advances in IL-2-based therapies, focusing on immunotoxins, immunocytokines, and IL-2 derivatives. Emphasis is placed on their role in combination strategies, showcasing their potential to target the TME and improve clinical outcomes effectively. Also, the use of IL-2 immunocytokines in "in situ" vaccination to relieve the immunosuppression of the TME is discussed.

Peripheral immune biomarkers for immune checkpoint inhibition of solid tumours

BACKGROUND

With the rapid adoption of immunotherapy for the treatment of cancer comes the pressing need for readily accessible biomarkers to guide immunotherapeutic strategies and offer insights into outcomes with specific treatments. Regular sampling of solid tumour tissues outside of melanoma for immune monitoring is not often feasible; conversely, routine, frequent interrogation of circulating immune biomarkers is entirely possible. As immunotherapies and immune checkpoint inhibitors, in particular, are more widely used in first-line, neoadjuvant, and metastatic settings, the discovery and validation of peripheral immune biomarkers are urgently needed across solid tumour types for improved prediction and prognostication of clinical outcomes in response to immunotherapy, as well as elucidation of mechanistic underpinnings of the intervention. Careful experimental design, encompassing both retrospective and prospective studies, is required in such biomarker identification studies, and concerted efforts are essential for their advancement into clinical settings.

CONCLUSION

In this review, we summarize shared immune features between the tumour microenvironment and systemic circulation, evaluate exploratory peripheral immune biomarker studies, and discuss associations between candidate biomarkers with clinical outcomes. We also consider integration of multiple peripheral immune parameters for better prediction and prognostication and discuss considerations in study design to further evaluate the clinical utility of candidate peripheral immune biomarkers for immunotherapy of solid tumours.

HIGHLIGHTS

Peripheral immune biomarkers are critical for improved prediction and prognostication of clinical outcomes for patients with solid tumours treated with immune checkpoint inhibition. Candidate peripheral biomarkers, such as cytokines, soluble factors, and immune cells, have potential as biomarkers to guide immunotherapy of solid tumours. Multiple peripheral immune parameters may be integrated to improve prediction and prognostication. The potential of peripheral immune biomarkers to guide immunotherapy of solid tumours requires critical work in biomarker discovery, validation, and standardization.

Hepatic artery infusion pump (HAIP) therapy in combination with targeted delivery of IL-12 for patients with metastatic colorectal cancer or intrahepatic cholangiocarcinoma: a phase II trial protocol

Background

Treatment of advanced liver tumors remains challenging. Although immune checkpoint inhibition has revolutionized treatment for many cancers, responses in colorectal liver metastases and biliary tract cancers remain suboptimal. Investigation into additional immunomodulatory therapies for these cancers is needed. Interleukin-12 (IL-12) is a pro-inflammatory cytokine with robust anti-tumor activity, but systemic adverse effects largely terminated therapeutic development of recombinant human IL-12 (rhIL-12). PDS01ADC is a novel human monoclonal antibody (NHS76) conjugated to two IL-12 heterodimers with established safety in phase I trials. The NHS76 antibody specifically targets histone/DNA complexes which are accessible only in regions of cell death and this antibody has been shown to accumulate locally in tumors.

Methods

Patients with unresectable metastatic colorectal cancer (mCRC) or unresectable intrahepatic cholangiocarcinoma (ICC) will receive synchronization of subcutaneous PDS01ADC with floxuridine delivered via a hepatic artery infusion pump (HAIP). The primary outcome measured in this study will be overall response rate as measured by Response Evaluation Criteria in Solid Tumors (RECIST) criteria. Secondary outcomes measured in this study will include hepatic and non-hepatic progression-free survival (PFS), overall survival, and safety of PDS01ADC combination therapy with HAIP.

Discussion

Poor clinical response of these liver tumors to immunotherapy is likely due to various factors, including poor immune infiltrate into the tumor and immunosuppression by the tumor microenvironment. By exploiting the tumor cell death induced by HAIP locoregional therapy in combination with systemic chemotherapy, PDS01ADC is poised to modulate the tumor immune microenvironment to improve outcomes for patients undergoing HAIP therapy.

Trial Registration

ClinicalTrials.gov (ID NCT05286814 version 2023-10-18); https://clinicaltrials.gov/study/NCT05286814?term=NCT05286814&rank=1.

Preclinical and clinical studies of a tumor targeting IL-12 immunocytokine

The clinical success of immune checkpoint inhibitors (ICIs) has demonstrated the promise and challenges of cancer immunotherapy. There is an unmet need to develop novel cancer therapies that can provide clinical benefit for most patients with solid malignancies, which harbor innate or acquired resistance to ICIs. Interleukin-12 (IL-12) is a promising cytokine for cancer therapy given its direct stimulatory effects on innate and adaptive immunity. However, unfavorable pharmacokinetics and a narrow therapeutic index render recombinant IL-12 (rIL-12) less attractive as a cancer therapy. NHS-IL12 is a fusion protein of IL-12 and NHS76 (human IgG1) antibody engineered to target single and double stranded DNA present in necrotic areas solid tumors. In preclinical tumor models, NHS-IL12 elicited significant Th1 immune activation and tumor suppressive effects, primarily mediated by NK and CD8+ T lymphocytes, with engagement of myeloid immunity. NHS-IL12 is currently being evaluated clinically in combination with various therapeutic modalities, including chemotherapy, radiation therapy, immune checkpoint inhibition, vaccines, and epigenetic modulation. Here we review the preclinical and clinical studies involving NHS-IL12 for the treatment of solid malignancies.