Tom's of Maine will provide more details on non-animal anticaries test method for FDA.

TOM'S OF MAINE TO PROVIDE FDA WITH DETAILS ON NON-ANIMAL ANTICARIES TEST in response to requests from agency representatives at a March 20 "OTC feedback" meeting in Rockville, Md. In place of the animal caries reduction test for dentifrices that will be required by FDA as of Oct. 7, Tom's of Maine petitioned FDA in February to accept data from an intra-oral remineralization test in humans as a method of measuring fluoride bioavailability ("The Rose Sheet" March 4, p. 7).

At the meeting, FDA asked for further details about the study protocol, such as the level of interaction of the dentifrice with saliva in the test versus actual product use. The company said it would provide the additional information in two to three weeks.

FDA announced that it would require a fluoride bioavailability test in the OTC anticaries drug products final monograph, which was published in the Oct. 6 Federal Register ("The Rose Sheet" Oct. 16, p. 6). Companies interested in using alternative test methods were asked by FDA to submit a petition supported by data demonstrating that the proposed method "provides results of equivalent accuracy."

Tom's of Maine, based in Kennebunk, Maine, promotes its toothpastes as "natural" and "cruelty-free" with "no saccharin or artificial sweeteners. No sweeteners. No preservatives. No artificial color or flavor and no animal ingredients."

Norman See, a pharmacologist with FDA's Dermatologic and Dental Drug Products Division, explained that knowing the extent to which a dentifrice is mixed with saliva would be valuable because "saliva contains a certain level of calcium," which could distort the remineralization test results. See suggested repeating the remineralization study using less calcium and possibly a different methodology. He also expressed concern that the saliva in the test was "not at the normal level of dilution."

The developer of the test method, Richard Corpron, DDS/PhD, University of Michigan School of Dentistry, noted that participants in the study applied the dentifrice for 60 seconds -- more than twice the 25 seconds most people usually brush -- in order to mimic the level of dilution in actual use of the toothpaste.

See, however, questioned whether the test method "would have the same degree of mixing with saliva as with the regular use of a dentifrice." Fred Hyman, dental officer in the dermatologic and dental division, agreed that the dilution level in the Tom's of Maine tests "is not the same" as the dilution that occurs with actual use.

The test makes use of enamel specimens -- some sound and others with simulated lesions -- that are mounted on a dental appliance and worn by test subjects. Corpron explained that the enamel specimens are "swabbed," not brushed, with the dentifrice because the artificial lesions are too delicate.

The study compared the efficacy of Tom's "original" Natural Toothpaste with Fluoride, a placebo (Tom's Natural Toothpaste without fluoride) and an active control, SmithKline Beecham's MacLean's dentifrice, which is no longer sold in the U.S. but was available in 1991 when the test was conducted. MacLean's was chosen because it contains the same active ingredient and abrasive as Tom's in a similar formulation, and also has been proven effective in clinical trials, Tom's of Maine explained.

The FDAers also asked Tom's of Maine to report exactly how the dentifrices were applied in the test and to clarify the results, which See described as "hard to follow." In addition, the agency asked the company to substantiate both the estimate that consumers brush for an average of 25 seconds as well as the general recognition of the test method's validity. Corpron stated that the test method is "well-accepted."

Tom's "original" toothpaste with fluoride, Chappell noted, accounts for 50-55% of the firm's approximately $20 mil. in annual sales. Tom's, which only recently began to be distributed nationally, holds about a 1% share of the U.S. market, but has a 3-4% share in regions where it is available, he said.

OTC Drug Products Division Director Debra Bowen, MD, acknowledged that FDA is "treading new ground" in considering the test method proposed by Tom's of Maine. However, Tom's reassured the agency that it does not believe any other companies are interested in using its test method.

"You're not on a slippery slope," Washington, D.C. attorney Nancy Buc told the agency, adding that there is "not a hint that anybody else is going in this direction."

Tom's President Tom Chappell remarked that the test method is more expensive than the required methods -- "$10,000 versus $140,000" -- and takes a longer time, "one month versus one year." Tom's is compelled to "go to any length to satisfy regulatory requirements" without conducting tests on animals, Chappell said, because "people won't tolerate Tom's doing animal testing."