Providing Patients with Critical or Life-Threatening Illnesses Access to Experimental Drug Therapy: A Guide to Clinical Trials and the US FDA Expanded Access Program

Preclinical rationale and current pathways to support the first human clinical trials in cardiac xenotransplantation

Recent initiation of the first FDA-approved cardiac xenotransplantation suggests xenotransplantation could soon become a therapeutic option for patients unable to undergo allotransplantation. Until xenotransplantation is widely applied in clinical practice, consideration of benefit versus risk and approaches to management of clinical xenografts will based at least in part on observations made in experimental xenotransplantation in non-human primates. Indeed, the decision to proceed with clinical trials reflects significant progress in last few years in experimental solid organ and cellular xenotransplantation. Our laboratory at the NIH and now at University of Maryland contributed to this progress, with heterotopic cardiac xenografts surviving more than two years and life-supporting cardiac xenografts survival up to 9 months. Here we describe our contributions to the understanding of the mechanism of cardiac xenograft rejection and development of methods to overcome past hurdles, and finally we share our opinion on the remaining barriers to clinical translation. We also discuss how the first in human xenotransplants might be performed, recipients managed, and graft function monitored.

Expanded Access Programs, compassionate drug use, and Emergency Use Authorizations during the COVID-19 pandemic

The US Food and Drug Administration (FDA) Expanded Access (EA) Program, which allows for compassionate uses of unapproved therapeutics and diagnostics outside of clinical trials, has gained significant traction during the Coronavirus 2019 (COVID-19) pandemic. While development of vaccines has been the major focus, uncertainties around new vaccine safety and effectiveness have spawned interest in other pharmacological options. Experimental drugs can also be approved under the FDA Emergency Use Authorization (EUA) program, designed to combat infectious disease and other threats. Here, we review the US experience in 2020 with pharmacological EA and EUA approvals during the pandemic. We also provide a description of, and clinical rationale for, each of the EA- or EUA-approved drugs (e.g. remdesivir, convalescent plasma, propofol 2%, hydroxychloroquine, ruxolitinib, bamlanivimab, baricitinib, casirivimab plus imdevimab) during the pandemic and concluding reflections on the EA program and its potential future uses.