Ocular safety: a silent (in vitro) success story.

Ocular irritation testing has been one of the animal test methods most criticised by animal welfare advocates. Additional criticism has arisen from within the scientific community, based on the variability of the animal test results and the questionable relevance of the extremely high dose levels employed. As a result, the Draize eye irritation test has been one of the main targets for in vitro replacement. Despite extensive efforts, however, there is still no in vitro method that is fully validated as a regulatory replacement. In spite of this, many individual companies are using diverse in vitro ocular irritation tests to gain important safety and efficacy information about their products and raw materials, eliminating the need for animal testing in the process. This is done in a safe fashion by applying intelligent testing paradigms. ECVAM has played a major role in this success, through its many programmes that have emphasised the importance of understanding the true toxicological need, and then using in vitro tests to provide that information. Thus, even in the absence of a successfully validated regulatory assay, the desired result of reducing animal testing is being met.