© JAVIER BROSCH/SHUTTERSTOCK.COMThe vast majority of novel anticancer compounds that show promise in laboratory studies and in animal models do not make it through the rigorous and challenging translational path necessary for approval by the US Food and Drug Administration. Multiple factors contribute to the extremely low rate of successful drug development, including unexpected toxicity and/or lack of efficacy in humans, after a candidate compound has shown promise in rodent studies. As a result, researchers have begun to develop more-accurate and more-predictive model systems, such as genetically engineered murine models or patient-derived xenograft models. (See “My Mighty Mouse,” The Scientist, April 2015.) But there may be another solution to this translational problem: comparative oncology.
Studying conserved tumor subtypes across multiple species provides a unique opportunity for the scientific community to improve the drug-development pathway, specifically through the inclusion of pet dogs and cats with naturally occurring cancers. Evaluation of novel agents in such pet animals can provide valuable information regarding drug metabolism, toxicity, pharmacokinetics, pharmacodynamics, efficacy, and biomarker discovery in the context of mammalian species more similar in physiology and body size to humans. In addition, companion animals develop cancers spontaneously under normal immune surveillance mechanisms, which more faithfully recapitulate the multistep progression that occurs in people. Therefore, studying canine and feline models of cancer can generate valuable safety and efficacy data to support the further development of novel therapies.
Over the past decade, the promise of such an ...