Animal models of sepsis and shock: a review and lessons learned

Over the past decade, the biotechnology/pharmaceutical industry has been diligently working on the development of immunomodulatory agents for the treatment of shock and sepsis, and the literature is rife with descriptions of novel and innovative molecules that promise to become the panacea for these conditions. Unfortunately, despite promising preclinical evidence, dozens of these new agents have failed to demonstrate clinical efficacy in controlled, randomized clinical trials, abandoning the bedside physician to the traditional armamentarium of drugs and therapeutics for the treatment of patients with these complex, progressive, and life-threatening conditions. The reasons for this quandary are controversial, complex, and multifactorial. This review focuses on the concept that the preclinical trials of many of these agents were conducted using models of sepsis and shock that do not adequately reflect the clinical realities of these conditions. As a result, it is not surprising that clinical trials of agents based on clinically flawed models failed to demonstrate clinical efficacy. The lack of clinical insight during preclinical development of these agents has contributed to the current impasse of the development of safe, efficacious, and potentially lifesaving agents for the treatment of shock and sepsis. Thus, the goal of this review article is to review the advantages and disadvantages of commonly used sepsis and shock models in light of lessons learned from these clinical trials.