Dose escalation and expansion phase I studies with the tumour-targeting antibody-tumour necrosis factor fusion protein L19TNF plus doxorubicin in patients with advanced tumours, including sarcomas

Molecular mechanisms of tumour necrosis factor signalling via TNF receptor 1 and TNF receptor 2 in the tumour microenvironment

Tumour necrosis factor (TNF) is a primary mediator of inflammatory processes by facilitating cell death, immune cell activation and triggering of inflammation. In the cancer context, research has revealed TNF as a multifaceted cytokine that can be both pro- or anti-tumorigenic depending on what context is observed. We explore the plethora of ways that TNF and its receptors manipulate the functional and phenotypic characteristics in the tumour microenvironment (TME) on both tumour cells and immune cells, promoting either tumour elimination or progression. Here, we discuss the latest cutting-edge TNF-focused biologics currently in clinical translation that modifies the TME to derive greater immune responses and therapeutic outcomes, and further give perspectives on the future of targeting TNF in the context of cancer by emerging technological approaches.

Facts and Hopes: Immunocytokines for Cancer Immunotherapy

The clinical development of cytokines as cancer therapeutics has been limited due to significant toxicities generally observed with systemic administration. This narrow therapeutic window, together with relatively modest efficacy, has made natural cytokines unattractive drug candidates. Immunocytokines represent a class of next-generation cytokines designed to overcome the challenges associated with traditional cytokines. These agents seek to improve the therapeutic index of cytokines by using antibodies as vehicles for the targeted delivery of immunomodulatory agents within the local tumor microenvironment (TME). Various molecular formats and cytokine payloads have been studied. In this review, we provide an overview of the rationale, preclinical support, and current clinical development strategies for immunocytokines.

Engineering cytokines for cancer immunotherapy: a systematic review

Cytokines are pivotal mediators of cell communication in the tumor microenvironment. Multiple cytokines are involved in the host antitumor response, but the production and function of these cytokines are usually dysregulated during malignant tumor progression. Considering their clinical potential and the early successful use of cytokines in cancer immunotherapy, such as interferon alpha-2b (IFNα-2b; IntronA^®) and IL-2 (Proleukin^®), cytokine-based therapeutics have been extensively evaluated in many follow-up clinical trials. Following these initial breakthroughs, however, clinical translation of these natural messenger molecules has been greatly limited owing to their high-degree pleiotropic features and complex biological properties in many cell types. These characteristics, coupled with poor pharmacokinetics (a short half-life), have hampered the delivery of cytokines via systemic administration, particularly because of severe dose-limiting toxicities. New engineering approaches have been developed to widen the therapeutic window, prolong pharmacokinetic effects, enhance tumor targeting and reduce adverse effects, thereby improving therapeutic efficacy. In this review, we focus on the recent progress and competitive landscape in cytokine engineering strategies and preclinical/clinical therapeutics for cancer. In addition, aiming to promote engineered cytokine-based cancer immunotherapy, we present a profound discussion about the feasibility of recently developed methods in clinical medicine translation.

T cell exhaustion in malignant gliomas

Despite advances in understanding tumor biology, malignant gliomas remain incurable. While immunotherapy has improved outcomes in other cancer types, comparable efficacy has not yet been demonstrated for primary cancers of the central nervous system (CNS). T cell exhaustion, defined as a progressive decrease in effector function, sustained expression of inhibitory receptors, metabolic dysfunction, and distinct epigenetic and transcriptional alterations, contributes to the failure of immunotherapy in the CNS. Herein, we describe recent advances in understanding the drivers of T cell exhaustion in the glioma microenvironment. We discuss the extrinsic and intrinsic factors that contribute to exhaustion and highlight potential avenues for reversing this phenotype. Our ability to directly target specific immunosuppressive drivers in brain cancers would be a major advance in immunotherapy.

What's the latest with investigational drugs for soft tissue sarcoma?

INTRODUCTION

Despite extensive research undertaken in the past 20-30 years, the treatment for soft tissue sarcoma (STS) has remained largely the same, with anthracycline-based chemotherapy remaining the first choice for treating advanced or metastatic STS.

AREAS COVERED

This review focuses on newly approved drugs for STS and current research directions, including recent results of late-phase trials in patients with STS. We cover several different histological subtypes, and we discuss the role of adoptive cell transfer (ACT) therapies for the treatment of synovial and myxoid/round cell (high-grade myxoid) liposarcoma, one of the most promising areas of treatment development to date. We searched clinicaltrials.gov and pubmed.ncbi.nih.gov, as well as recent year proceedings from the annual conferences of the American Society of Clinical Oncology (ASCO), European Society for Medical Oncology (ESMO), and Connective Tissue Oncology Society (CTOS).

EXPERT OPINION

Immune-oncology drugs (IOs) show promise in certain subtypes of STS, but it is recognized that PD-1/PD-L1 axis inhibition is not enough on its own. Better trial stratifications based on the molecular categorization of different subtypes of STS are needed, and more evidence suggests that 'one size fits all' treatment is no longer sustainable in this heterogeneous and aggressive group of tumors.

Generation and in vivo validation of an IL-12 fusion protein based on a novel anti-human FAP monoclonal antibody

BACKGROUND

In this study, we describe the generation of a fully human monoclonal antibody (named '7NP2') targeting human fibroblast activation protein (FAP), an antigen expressed in the microenvironment of different types of solid neoplasms.

METHODS

7NP2 was isolated from a synthetic antibody phage display library and was improved by one round of mutagenesis-based affinity maturation. The tumor recognition properties of the antibody were validated by immunofluorescence procedures performed on cancer biopsies from human patients. A fusion protein consisting of the 7NP2 antibody linked to interleukin (IL)-12 was generated and the anticancer activity of the murine surrogate product (named mIL12-7NP2) was evaluated in mouse models. Furthermore, the safety of the fully human product (named IL12-7NP2) was evaluated in Cynomolgus monkeys.

RESULTS

Biodistribution analysis in tumor-bearing mice confirmed the ability of the product to selectively localize to solid tumors while sparing healthy organs. Encouraged by these results, therapy studies were conducted in vivo, showing a potent antitumor activity in immunocompetent and immunodeficient mouse models of cancer, both as single agent and in combination with immune checkpoint inhibitors. The fully human product was tolerated when administered to non-human primates.

CONCLUSIONS

The results obtained in this work provided a rationale for future clinical translation activities using IL12-7NP2.

An Attenuated Targeted-TNF Localizes to Tumors In Vivo and Regains Activity at the Site of Disease

Antibody-cytokine fusion proteins (immunocytokines) are gaining importance for cancer therapy, but those products are often limited by systemic toxicity related to the activity of the cytokine payload in circulation and in secondary lymphoid organs. Tumor necrosis factor (TNF) is used as a pro-inflammatory payload to trigger haemorrhagic necrosis and boost anti-cancer immunity at the tumor site. Here we describe a depotentiated version of TNF (carrying the single point mutation I97A), which displayed reduced binding affinity to its cognate receptor tumor necrosis factor receptor 1 (TNFR-1) and lower biocidal activity. The fusion of the TNF(I97A) mutant to the L19 antibody promoted restoration of anti-tumor activity upon accumulation on the cognate antigen, the alternatively spliced EDB domain of fibronectin. In vivo administration of high doses (375 μg/Kg) of the fusion protein showed a potent anti-tumor effect without apparent toxicity compared with the wild type protein. L19-TNFI97A holds promise for the targeted delivery of TNF activity to neoplastic lesions, helping spare normal tissues.