Current challenges in the evaluation of cardiac safety during drug development: translational medicine meets the Critical Path Initiative.

In October 2008, in a public forum organized by the Cardiac Safety Research Consortium and the Health and Environmental Sciences Institute, leaders from government, the pharmaceutical industry, and academia convened in Bethesda, MD, to discuss current challenges in evaluation of short- and long-term cardiovascular safety during drug development. The current paradigm for premarket evaluation of cardiac safety begins with preclinical animal modeling and progresses to clinical biomarker or biosignature assays. Preclinical evaluations have clear limitations but provide an important opportunity to identify safety hazards before administration of potential new drugs to human subjects. Discussants highlighted the need to identify, develop, and validate serum and electrocardiogram biomarkers indicative of early drug-induced myocardial toxicity and proarrhythmia. Specifically, experts identified a need to build consensus regarding the use and interpretation of troponin assays in preclinical evaluation of myocardial toxicity. With respect to proarrhythmia, the panel emphasized a need for better qualitative and quantitative biomarkers for arrhythmogenicity, including more streamlined human thorough QT study designs and a universal definition of the end of the T wave. Toward many of these ends, large shared data repositories and a more seamless integration of preclinical and clinical testing could facilitate the development of novel approaches to both cardiac safety biosignatures. In addition, more thorough and efficient early clinical studies could enable better estimates of cardiovascular risk and better inform phase II and phase III trial design. Participants also emphasized the importance of establishing formal guidelines for data standards and transparency in postmarketing surveillance. Priority pursuit of these consensus-based directions should facilitate both safer drugs and accelerated access to new drugs, as concomitant public health benefits.