An FDA analysis of clinical hold deficiencies affecting investigational new drug applications for oncology products

Clinical holds for cell and gene therapy trials: Risks, impact, and lessons learned

The recent increase in cell and gene therapies being developed has been coupled with a disproportionate increase in Food and Drug Administration (FDA)-mandated clinical holds. Aiming to better understand causes and secondary effects of these clinical holds on biotechnology companies, we analyzed 33 clinical holds that were publicly announced from January 2020 to December 2022. Approximately 80% of the analyzed clinical holds were formally lifted by the close of our study after an average of 6.2 months, and several trials have had significant clinical success following a hold. CAR T cell therapies accounted for nine holds, Lentiviral and AAV-based gene therapies accounted for five and 15 holds, respectively, and other cell and gene therapies accounted for four holds. The most common trigger was an adverse event or patient death. To remove a hold, protocol amendments were the most requested resolution by FDA. While there is no way to guarantee a therapy will not be placed on clinical hold, especially following unexpected adverse events, some deficiencies are avoidable. Utilizing FDA-provided resources on regulations and expectations for cell and gene therapy investigational new drug applications, inclusion of an external safety monitoring board, and a proactive risk assessment plan may prevent a clinical hold or result in a shortened duration.

The FDA Oncology Center of Excellence Scientific Collaborative: Charting a Course for Applied Regulatory Science Research in Oncology

The FDA Oncology Center of Excellence (OCE) is a leader within the agency in scientific outreach activities and regulatory science research. On the basis of analysis of scientific workshops, internal meetings, and publications, the OCE identified nine scientific priority areas and one cross-cutting area of high interest for collaboration with external researchers. This article describes the process for identifying these scientific interest areas and highlights funded and unfunded opportunities for external researchers to work with FDA staff on critical regulatory science challenges.

Analysis of Suspension of Clinical Trials for Drug Registration in China

Suspension is an important risk control measure during clinical trials. We investigated the use of this in China and identified common reasons for suspension by analyzing trends, hold issues, outcomes, background and design characteristics of suspended clinical drug trials from January 1, 2013 to December 1, 2019. A total of 298 clinical trials during the study timeframe were registered, accounting for 3.1% of all clinical drug trials. Numbers and proportion of clinical trials suspended based on benefit/risk factors have been increasing without holds on registrations by Center for Drug Evaluation. Reasons for suspension vary among trial phases, benefit and risk factors, protocol issues etc. 67% of trials that have been on hold for >1 year were still on hold at the time of this analysis. Children and the elderly were enrolled in 4.1% and 41% of the suspended trials, respectively. Strengthening regulation of pre-market pharmacovigilance through optimizing reporting and monitoring of safety information during clinical trial is thus needed. Establishing a closed-loop treatment mechanism for trial suspension is also important. Examination of potential risks, such as the quality of protocols, the ability of the institution to support the trial, and the adequacy of supplies of the investigational product is needed before beginning clinical trials. More careful evaluation at the drug registration phase will reduce the frequency of suspension and protect subjects after suspension occurs.

Risk Minimization of Antibody-Drug Conjugates in Oncology: A Review

Antibody-drug conjugates (ADCs) are new treatment options for certain cancers, especially those in advanced states with limited treatment options. Their unique design provides targeted therapy with toxins that otherwise would not be available, but they manifest toxicities that require risk minimization interventions to optimize their tolerability. We summarize selected toxicities for ADCs that have been approved through the end of 2020 and three investigational ADCs, which include both payload and linker, as described in the US Prescribing Information, the European Summary of Product Characteristics, and study protocols. These toxicities include peripheral neuropathy; pulmonary, skin, hepatic, and ocular toxicities; hyperglycemia; left ventricular dysfunction; and fluid-related events. We also review the risk minimization approaches to managing these toxicities as described in the product labels and study protocols. Our general observation suggests that the selected toxicities of the approved ADCs are primarily associated with off-target effects of the drug payloads. We also observed that the risk minimization approaches used to manage the selected toxicities are similar across product labels and study protocols. ADCs provide a unique treatment approach that is currently focused on advanced or refractory cancers. The risk minimization approaches for the selected toxicities for the approved ADCs per product label, or the study protocol for those in clinical investigation, are similar to those of standard chemotherapy agents and other pharmaceutical agents for the treatment of advanced malignancies. These risk minimization measures align with standard medical practice and are likely familiar to and feasible for physicians who prescribe for, and to other healthcare practitioners who care for, patients treated with ADCs.