The role of animal models in evaluating reasonable safety and efficacy for human trials of cell-based interventions for neurologic conditions.

Progress in regenerative medicine seems likely to produce new treatments for neurologic conditions that use human cells as therapeutic agents; at least one trial for such an intervention is already under way. The development of cell-based interventions for neurologic conditions (CBI-NCs) will likely include preclinical studies using animals as models for humans with conditions of interest. This paper explores predictive validity challenges and the proper role for animal models in developing CBI-NCs. In spite of limitations, animal models are and will remain an essential tool for gathering data in advance of first-in-human clinical trials. The goal of this paper is to provide a realistic lens for viewing the role of animal models in the context of CBI-NCs and to provide recommendations for moving forward through this challenging terrain.

The implications of advances in neuroscience for freedom of the will.

Some neuroscientists argue that advances in neuroscience threaten to undermine our freedom. The argument here is that those concerns are instances of a more general concern about the compatibility of freedom with causal determinism, and that denying that our choices are fully determined under causal laws presents a different set of problems for the claim that we have free will. An alternative account of freedom is presented, consistent with determinism in general, and with advances in neuroscience in particular.

Safety issues in cell-based intervention trials.

We report on the deliberations of an interdisciplinary group of experts in science, law, and philosophy who convened to discuss novel ethical and policy challenges in stem cell research. In this report we discuss the ethical and policy implications of safety concerns in the transition from basic laboratory research to clinical applications of cell-based therapies derived from stem cells. Although many features of this transition from lab to clinic are common to other therapies, three aspects of stem cell biology pose unique challenges. First, tension regarding the use of human embryos may complicate the scientific development of safe and effective cell lines. Second, because human stem cells were not developed in the laboratory until 1998, few safety questions relating to human applications have been addressed in animal research. Third, preclinical and clinical testing of biologic agents, particularly those as inherently complex as mammalian cells, present formidable challenges, such as the need to develop suitable standardized assays and the difficulty of selecting appropriate patient populations for early phase trials. We recommend that scientists, policy makers, and the public discuss these issues responsibly, and further, that a national advisory committee to oversee human trials of cell therapies be established.