Are local tolerance tests in animals always necessary?

Area of Science:

• Toxicology
• Ocular Safety Assessment
• Pharmacokinetics

Background:

• The Draize test, established in 1944, is a standard in vivo method for assessing chemical eye and skin irritation.
• Regulatory agencies widely use the Draize test for evaluating the eye tolerance of chemicals.
• Ethical and scientific concerns render the traditional Draize test obsolete.

Purpose of the Study:

• To propose an alternative to the in vivo Draize test for ocular safety assessment.
• To introduce and validate an in vitro technique for evaluating chemical eye irritation.
• To demonstrate the utility of an in vitro system for quantifying corneal drug uptake.

Main Methods:

• Development of an in vitro corneal perfusion system using a bovine cornea.
• The bovine cornea is maintained in physiological conditions for six hours.
• The system allows for simultaneous ocular toxicity evaluation and drug uptake quantification.

Main Results:

• The in vitro corneal perfusion system provides reproducible results.
• This method serves as a viable replacement for in vivo eye irritation tests.
• The system enables accurate quantitation of corneal drug uptake.

Conclusions:

• The in vitro corneal perfusion system is a scientifically sound and ethical alternative to the Draize test.
• This technique is suitable for ocular toxicological studies.
• The system can be applied to pharmacokinetic modeling for ocular drug delivery.