Nonclinical safety assessment of engineered T cell therapies

EMA commentary on the guideline on quality, nonclinical and clinical aspects of medicinal products containing genetically modified cells

Great advances have been made in the knowledge of development and regulatory approval of medicinal product containing genetically modified cells. Although a guideline has been available in the EU since 2012, the current updated version provides a useful guide to developers and professionals involved in the regulatory process of these medicines. This article presents the main issues communicated in that guidance, the regulators' insights and a commentary from the academic developers' point of view.

A roadmap towards a human-centric safety assessment of advanced therapy medicinal products

Advanced therapy medicinal products (ATMPs) are among the most complex pharmaceuticals with high human specificity. Species differences severely limit the clinical relevance of in vivo data. We conducted interviews with stakeholders involved in ATMP development about their perspective on the use of in vivo studies, the perceived hurdles and associated potential solutions regarding non-clinical development of ATMPs. In total, 17 stakeholders from 9 different countries were interviewed. A workshop was held with key stakeholders to further discuss major topics identified from the interviews. Conducting in vivo studies remains the status quo for ATMPs development. The hurdles identified included determining the amount of information required before clinical entry and effective use of limited human samples to understand a treatment or for clinical monitoring. A number of key points defined the need for future in vivo studies as well as improved application and implementation of New Approach Methodology (NAM)-based approach for products within a well-known modality or technology platform. These included data transparency, understanding of the added value of in vivo studies, and continuous advancement, evaluation, and qualification of NAMs. Based on the outcome of the discussions, a roadmap with practical steps towards a human-centric safety assessment of ATMPs was established.

The screening, identification, design and clinical application of tumor-specific neoantigens for TCR-T cells

Recent advances in neoantigen research have accelerated the development of tumor immunotherapies, including adoptive cell therapies (ACTs), cancer vaccines and antibody-based therapies, particularly for solid tumors. With the development of next-generation sequencing and bioinformatics technology, the rapid identification and prediction of tumor-specific antigens (TSAs) has become possible. Compared with tumor-associated antigens (TAAs), highly immunogenic TSAs provide new targets for personalized tumor immunotherapy and can be used as prospective indicators for predicting tumor patient survival, prognosis, and immune checkpoint blockade response. Here, the identification and characterization of neoantigens and the clinical application of neoantigen-based TCR-T immunotherapy strategies are summarized, and the current status, inherent challenges, and clinical translational potential of these strategies are discussed.

Biological and Molecular Factors Predicting Response to Adoptive Cell Therapies in Cancer

Adoptive cell therapy (ACT) constitutes a major breakthrough in cancer management that has expanded in the past years due to impressive results showing durable and even curative responses for some patients with hematological malignancies. ACT leverages antigen specificity and cytotoxic mechanisms of the immune system, particularly relying on the patient’s T lymphocytes to target and eliminate malignant cells. This personalized therapeutic approach exemplifies the success of the joint effort of basic, translational, and clinical researchers that has turned the patient’s immune system into a great ally in the search for a cancer cure. ACTs are constantly improving to reach a maximum beneficial clinical response. Despite being very promising therapeutic options for certain types of cancers, mainly melanoma and hematological malignancies, these individualized treatments still present several shortcomings, including elevated costs, technical challenges, management of adverse side effects, and a limited population of responder patients. Thus, it is crucial to discover and develop reliable and robust biomarkers to specifically and sensitively pinpoint the patients that will benefit the most from ACT as well as those at higher risk of developing potentially serious toxicities. Although unique readouts of infused cell therapy success have not yet been identified, certain characteristics from the adoptive cells, the tumor, and/or the tumor microenvironment have been recognized to predict patients’ outcome on ACT. Here, we comment on the importance of biomarkers to predict ACT chances of success to maximize efficacy of treatments and increase patients’ survival.