RICH-VICKS VAPORUB/VAPOSTEAM FINAL FORMULATION TEST PROTOCOL

RICH-VICKS VAPORUB/VAPOSTEAM FINAL FORMULATION TEST PROTOCOL to show decongestant efficacy was proposed in a July 10 letter to FDA's Division of OTC Drugs. The proposal modifies previous suggested protocols which would test separate ingredients. The company said it would submit results of the study under the new protocol to the OTC rulemaking for combination drugs after its publication. Modifications of the Vaporub protocol involve testing the decongestant activity of "a mixture of three aromatics (menthol, eucalyptus, and camphor)" versus a petrolatum placebo, instead of testing the ingredients individually as in the earlier protocol, the letter said. The firm also proposed statistical evaluation changes, reflecting suggestions made by FDA in a Nov. 6, 1986 feedback letter. Rich-Vicks met with representatives of FDA's OTC drug evaluation division on July 23 to discuss the design of the protocols. Although the director of the OTC division, William Gilbertson, PharmD, told the firm that it was too soon to make formal feedback comments, he suggested the firm could conduct the study without feedback. James Sorrentino, PhD, VP & Director, Rich-Vicks Health Care Products Division agreed, but said "we bump into problems when we do that because we end up with this baseline problem." He stated that feedback was needed on the protocols, which were changed on the basis of FDA's statements. According to Sorrentino, FDA said that the Rich-Vicks Vaposteam study had problems of improper use of baseline values, homogeneity, non-homogeneity, and variances. Rich-Vicks previously addressed these questions in a Feb. 19, 1987 letter to the agency. Concerning baseline values, Rich-Vicks' principal statistician, Robert Bartizek, maintained "we have relooked at our baseline calculations." He noted that the 1982 studies proposed averaging both the immediate [zero minute] and the 15 minute pretreatment reading should there be differences between them, in order to get a more precise baseline. But "that seemed to cause confusion so we eliminated that idea in all of our new protocols." The company now proposes to use just the zero pretreatment reading. Bartizek addressed FDA's suggestion, made in the February letter, that the firm include a nonparametric approach in any reanalysis. "We did an original parametric analysis, [and] used a live transformation, followed by an analysis of variance using zero minutes. . . We then went back and did a nonparametric analysis using zero minutes as the baseline. We did this for completeness." The Rich-Vicks' researchers then repeated the parametric analysis with the average of the zero and the 15 minute pretreatment reading, Bartizek said, and "all three of those gave us statistical significant advantages for all of the individual ingredients." Sherwin Straus, FDA Surgical-Dental Products Division, suggested that Rich-Vicks "wait for our feedback and then you can use that to make a protocol." Gilbertson told Straus that since he had not had time to look at the new Rich-Vicks protocol, he would like to see Straus' analysis in the next two weeks. The director of the OTC division then assured Rich-Vicks they would "get feedback maybe after Labor Day."