Are researchers moving away from animal models as a result of poor clinical translation in the field of stroke? an analysis of opinion papers

Objectives Despite decades of research using animals to develop
pharmaceutical treatments for stroke patients, few therapeutic options
exist. The vast majority of interventions successful in preclinical animal
studies have turned out to have no efficacy in humans, or to be harmful to
humans. In view of this we explore whether there is evidence of a move
away from animal models in this field. Methods We used an innovative
methodology, the analysis of opinion papers. Although we took a systematic
approach to literature searching and data extraction, this is not a
systematic review because the study involves the synthesis of opinions,
not research evidence. Data were extracted from retrieved papers in
chronological order and analysed qualitatively and descriptively. Results
Eighty eligible papers, published between 1979 and 2018, were identified.
Most authors were from academic departments of neurology, neuroscience or
stroke research. Authors agreed that translational stroke research was in
crisis. They held diverse views about the causes of this crisis, most of
which did not fundamentally challenge the use of animal models. Some,
however, attributed the translational crisis to animal-human species
differences and one to a lack of human in vitro models. Most of the
proposed solutions involved fine-tuning animal models but authors
disagreed about whether such modifications would improve translation. A
minority suggested using human in vitro methods alongside animal models.
One proposed focusing only on human based in vitro methods. Conclusion
Despite recognising that animal models have been unsuccessful in the field
of stroke, most researchers exhibited a strong resistance to relinquishing
them. Nevertheless there is an emerging challenge to the use of animal
models, in the form of human focused in vitro approaches. For the sake of
stroke patients there is an urgent need to revitalise translational stroke
research and explore the evidence for these new approaches.