Regulatory Assessment of Casgevy for the Treatment of Transfusion-Dependent ß-Thalassemia and Sickle Cell Disease with Recurrent Vaso-Occlusive Crises.

Sickle cell disease (SCD) and transfusion-dependent ß-thalassemia (TDT) are hereditary haemoglobinopathies characterized by a reduction in functional ß-globin chains. Both conditions cause tiredness and increase susceptibility to infection, which can lead organ failure, significantly reducing life expectancy and typically requiring those affected to undergo regular erythrocyte transfusion. Recently, a novel therapeutic treatment for SCD and TDT was approved by the UK regulatory body (Medicines and Healthcare products Regulatory Agency; MHRA). Exagamglogene autotemcel (Casgevy) is the first licensed therapy globally to utilize CRIPSR/Cas9 technology and induces an increase in expression of γ-globin chains to compensate for the reduction in functional ß-globin. Casgevy represents a first-in-class therapeutic, and numerous considerations were made by the MHRA throughout its assessment of the medicine. These include, but are not limited to, the risk of tumorigenicity and off-target editing, a limited cohort size, the validity of proposed dosing and the conduction of only single-arm studies. The MHRA's analyses of the data to support the proposed indications are presented and discussed throughout this manuscript. Overall, the sponsors claims were considered well supported by their data, and Casgevy was licensed for the treatment of TDT or SCD in patients 12 years of age and older for whom hematopoietic stem cell (HSC) transplantation is appropriate, but a human leukocyte antigen-matched related HSC donor is not available.

Preclinical Development of Cell-Based Products: a European Regulatory Science Perspective.

PURPOSE: This article describes preclinical development of cell-based medicinal products for European markets and discusses European regulatory mechanisms open to developers to aid successful product development. Cell-based medicinal products are diverse, including cells that are autologous or allogeneic, have been genetically modified, or not, or expanded ex vivo, and applied systemically or to an anatomical site different to that of their origin; comments applicable to one product may not be applicable to others, so bespoke development is needed, for all elements - quality, preclinical and clinical. METHODS: After establishing how the product is produced, proof of potential for therapeutic efficacy, and then safety, of the product need to be determined. This includes understanding biodistribution, persistence and toxicity, including potential for malignant transformation. These elements need to be considered in the context of the intended clinical development. RESULTS: This article describes regulatory mechanisms available to developers to support product development that aim to resolve scientific issues prior to marketing authorization application, to enable patients to have faster access to the product than would otherwise be the case. CONCLUSIONS: Developers are encouraged to be aware of both the scientific issues and regulatory mechanisms to ensure patients can be supplied with these products.

Correction to: Preclinical Development of Cell-Based Products: a European Regulatory Science Perspective.

The article [Preclinical Development of Cell-Based Products: a European Regulatory Science Perspective], written by [James W. McBlane, Parvinder Phul, and Michaela Sharpe], was originally published electronically on the publisher's internet portal (currently SpringerLink).

Regulatory landscape for cell therapy--EU view.

This article addresses regulation of cell therapies in the European Union (EU), covering cell sourcing and applications for clinical trials and marketing authorisation applications. Regulatory oversight of cell sourcing and review of applications for clinical trials with cell therapies are handled at national level, that is, separately with each country making its own decisions. For clinical trials, this can lead to different decisions in different countries for the same trial. A regulation is soon to come into force that will address this and introduce a more efficient clinical trial application process. However, at the marketing authorisation stage, the process is pan-national: the Committee for Human Medicinal Products (CHMP) is responsible for giving the final scientific opinion on all EU marketing authorisation applications for cell therapies: favourable scientific opinions are passed to the European Commission (EC) for further consultation and, if successful, grant of a marketing authorisation valid in all 28 EU countries. In its review of applications for marketing authorisations (MAAs) for cell therapies, the CHMP is obliged to consult the Committee for Advanced Therapies (CAT), who conduct detailed scientific assessments of these applications, with assessment by staff from national regulatory authorities and specialist advisors to the regulators.

Preclinical safety testing for cell-based products using animals.

The objectives of preclinical testing include to show why there might be therapeutic benefit in patients and to provide information on the product's toxicity. For cell-based products, given even once, there may be long term exposure and this could imply, unlike for conventional drugs, that all preclinical studies may be needed prior to first human use. The duration of exposure to cells should be studied in animals to guide toxicity assessments. Distribution of cells after administration by a route resembling that intended in humans should be studied to understand potential risks. Risk of tumour formation with the product may also need to be characterised. To the extent that this information can be generated by in vitro testing, studies in animals may not be needed and limitations on the capability of preclinical data to predict human toxicity are recognised: species-specificity make some cell products act only in humans and a human cell-product might be expected to be rejected by immunocompetent animals. Does this suggest testing in immunosuppressed animals or of development of an animal-cell product supposedly similar to the human cell product? No single answer seems to fit every situation.

A regulatory perspective of clinical trial applications for biological products with particular emphasis on Advanced Therapy Medicinal Products (ATMPs).

The safety of trial subjects is the tenet that guides the regulatory assessment of a Clinical Trial Authorization application and applies equally to trials involving small molecules and those with biological/biotechnological products, including Advanced Therapy Medicinal Products. The objective of a regulator is to ensure that the potential risk faced by a trial subject is outweighed by the potential benefit to them from taking part in the trial. The focus of the application review is to assess whether risks have been identified and appropriate steps taken to alleviate these as much as possible. Other factors are also taken into account during a review, such as regulatory requirements, and emerging non-clinical and clinical data from other trials on the same or similar products. This paper examines the regulatory review process of a Clinical Trial Authorization application from the perspectives of Quality, Non-Clinical and Clinical Regulatory Assessors at the Medicines and Healthcare products Regulatory Agency. It should be noted that each perspective has highlighted specific issues from their individual competence and that these can be different between the disciplines.