Non-Animal Test Method to Determine the Ocular Safety of Consumer Products and Chemicals: Phase II

ABSTRACT The phase I SBIR application, from which this phase II application is a continuation, was in response to the NIEHS solicitation for “Improved Test Systems for Prioritization and Safety Evaluation.” Specifically, the application was written to address the need for a nonanimal ocular safety test to differentiate ocular nonirritant substances from irritant and corrosive substances. Ocular safety tests are routinely conducted on live animals with a time to results of up to 21 days and are considered by many to be inhumane. Recent government legislation and consumer pressure are directed at reducing or eliminating the use of live animals for the routine testing of consumer products and cosmetics. However, limited options exist for nonanimal testing. Currently, accepted nonanimal test methods require the advanced purchase (up to three weeks) of live tissues and a technician skilled in aseptic technique; additionally, such tests are unable to classify compounds that cause reversible irritation, do not have a long shelf life, often misclassify ocular corrosives as nonirritants, take a long time (both hands-on and incubation), and require other advanced laboratory techniques including cell culture or dissection and subjective interpretation of ocular lesions. The subject of this proposal is the production of a rapid, irritancy-predictive, quantitative, standardized test kit with a one-year shelf life to provide standardized results more accurately and with higher sensitivity than any other available nonanimal ocular irritation test. SUCCESSFUL COMPLETION OF ALL SBIR PHASE I AIMS Using chemicals selected and coded by a government agency (NICEATM), and evaluated by representatives from U.S. governmental agencies [ICCVAM Ocular Toxicology Working Group (OTWG)], the phase I SBIR demonstrated that the test kit has a transferability of 92%, according to results from a blind transferability study. For the detection of nonirritants, out of the 90 chemicals evaluated, no GHS false-negative results were obtained (100% sensitivity). The overall sensitivity and accuracy outperformed all other available nonanimal ocular irritation test methods. In addition to the test being rapid and shelf stable, test kit performance for the detection of nonirritant compounds was excellent. Only a limited number of ocular corrosives were included in the validation study. While the overall sensitivity for ocular corrosives was 87%, only 16 ocular corrosives were tested in total. Additional validation with an increased number of ocular corrosives will better define the sensitivity of the method and improve confidence in the results. AIMS OF THE PHASE II APPLICATION During the first year of the phase II project, we propose to further optimize the test kit and convert manufacturing to full GMPs. During the second year of the project, we propose a second, larger and more complete validation study with 90–140 substances, tested in triplicate. As selected by NICEATM and the OTWG, we will test a large number of coded ocular corrosives, irritants, and nonirritants, representative of different chemical and physical classes. NICEATM has already agreed to select, purchase, and provide these substances to us in coded form without charge. Concurrently, since the test is already in kit form, we will initiate low-volume kit sales, scale up GMP production operations, and seek regulatory approval through the U.S. government (NICEATM and ICCVAM) and worldwide (OECD). Additional development and validation studies are required to better define accuracy (EPA classes I, II, III, and IV, and GHS categories 1, 2, and NC) and determine whether the test is able to detect compounds in all classes of irritants, ranging from slight irritants to corrosives. In addition, we will scale up and convert production operations to full GMP production. Concomitantly, we will seek worldwide regulatory acceptance through the OECD. An accurate, multiclass, rapid, stable, nonanimal eye safety test kit represents a significant business opportunity in the current market of consumer products and cosmetics, and will make available an accurate, validated, humane, and standardized test kit that will provide a needed solution to both private industry and regulatory agencies.PROJECT NARRATIVE There is an unmet regulatory need for a non-animal eye safety test that can be kept stably on the shelf and then quickly, accurately, and reliably employed to determine whether an unknown product or chemical is an ocular hazard. In the phase I grant it was shown that the test kit provides high sensitivity, reliable results in less than 24 hours by third parties. Phase II will refine the method and commercial potential of the project, scale up production and seek regulatory acceptance.