Translational medicine for stroke drug discovery: the pharmaceutical industry perspective.

Over the past 20 years, an estimated $1 billion has been spent in research and development of stroke therapeutics; however, this huge investment has failed to produce a clinically efficacious drug with the exception of the thrombolytic agent Activase (tPA). This sobering reality has been the subject of numerous reflections by renowned leaders in stroke research with special focus on the most recent failed clinical trials. The validity of the neuroprotection strategy has been questioned and efforts to substantially modify the quality of stroke research have been examined. The consistent failures of the pharmaceutical industry to develop a neuroprotective drug for ischemic stroke have had a major impact on the assessment of stroke as an attractive therapeutic area for drug discovery. Many pharmaceutical companies have scaled down their stroke programs, reflecting skepticism about the prospect of contemporary stroke drug discovery strategy based on neuroprotective agents. In this article, we present a Translational Medicine perspective on critical issues that the pharmaceutical industry and the academic community encounter but often ignore during stroke therapeutic development. This Translational Medicine framework offers a systematic analysis of the possible deficiencies that likely underwrote the colossal failure of clinical trials with neuroprotective drugs. In addition, we offer a biomarker-based system that aims at providing "proof of concept" along the discovery and development pipeline, which if implemented along early preclinical and clinical development phases, might significantly reduce risks and enable success.