The SOT/Eurotox Debate was held Monday afternoon to debate the statement: “In vitro Alternatives Are Ready to be implemented and relied upon for safety testing.” For those not familiar with the format of this session, two thought leaders are charged with taking and arguing opposing views. While this sounds like it may just be an entertaining exercise, each year this debate really serves to mark the progress on the path moving towards greater understanding and acceptance of new non-animal models. This year the debaters were George Daston from Procter and Gamble and Maurice Whalen from EURL/ECVAM. Dr. Daston took the proponent view and Dr. Whalen took the opposing view.
The proponent view taken by Dr. Daston included reminding the audience that unlike 40 years ago, we rarely enter into a question about safety blind to any information. With the voluminous amounts of data and databases, the read-across principle is already being used to make lower level decisions about chemicals in commerce, be it food, industrial and consumer chemicals, or therapeutics. In other words, these datasets are already being used to make early safety decisions. The next step is a battery of in vitro tests designed to address the issues that arise from a read-across analysis. In other words, the body of data accessible allows a hypothesis driven approach, rather than hypothesis-free as is historically the approach in safety testing.
The opposing view taken by Dr. Whalen walked the audience through three key missing elements of current In vitro tests, which is their reliability, their relevance, and their acceptance. The reliability of these methods is poor because often methods are generated in research environments and the methods are not described well enough for another lab to replicate the process. The challenge of relevance arises from the inability to replicate in vivo exposure, difficulty replicating higher order cellular interactions, and that the integrated approaches touted by proponents are not actually well integrated. The final point was acceptance. To gain acceptance, these methods need to be easily understood and practical, whereas currently stakeholders are often presented with “heat maps galore” with a promise to integrate the data. At the end of the day, Dr. Whalen said, it’s important that if we are to replace animal models that we are to do it with “something better, not something equally as bad.”
Audience applause was measured to determine the winner of the debate and Dr. Whalen won hands down; with cheers even. However, it’s important to note that Dr. Whalen did show about a dozen regulatory accepted methods using only in vitro tools. While proclaiming that the biology underlying these methods was simple compared with many targets, an audience member pointed out that this was perhaps throwing the baby out with the bath water. It seems there is a place for in vitro tests currently to fill in some of the gaps and open questions left by animal models, but even for that to become reality, the analysis and interpretation of in vitro tests will need to be more accessible. In other words, the tools now need to be converted to solutions.
This blog discusses highlights from the SOT Annual Meeting and ToxExpo Session: SOT/Eurotox Debate: In vitro Alternatives Are Ready to Be Implemented and Relied Upon for Human Safety Testing