VITARINE's TRIAMTERENE/HYDROCHLOROTHIAZIDE WILL BE ONLY GENERIC VERSION OF MYLAN's MAXZIDE ON MARKET UNTIL APRIL 17; FIRM's ANDA APPROVED DEC. 8

Vitarine will be the exclusive marketer of a generic version of Mylan's Maxzide until April 17, 1988, following FDA approval of the company's ANDA on Dec. 8. Vitarine received 180-days exclusivity, beginning Oct. 20, as the first ANDA applicant for the triamterene/hydrochlorothiazide 75 mg/50 mg product to challenge successfully Mylan's formulation patent on Maxzide ("The Pink Sheet" Nov. 9, p. 3). Vitarine plans to begin contacting the generic trade during the week of Dec. 14. The Springfield Gardens, New York-based firm sells primarily to own-label distributors and, to a lesser extent, smaller distributors under the Vitarine label. Although Vitarine was not the first company to obtain approved for a generic version of Maxzide, the firm's exclusivity for the product ensures that it will be the only generic manufacturer for four months. The triamterene/hydrochlorothiazide combo, in effect, will be the fifth product for which the firm was first to receive ANDA approval during 1987. During the year, privately held Vitarine received the first ANDA approvals for sustained-release indomethacin, trimipramine capsules, cephalexin capsules and desipramine tablets. FDA also granted approval to Barr Labs on Dec. 8 for the triamterene/hydrochlorothiazide combination. In its approval letter, FDA explained that the effective date of the approval is delayed until April 17, 1988 because of Vitarine's exclusivity. Barr Labs and American Therapeutics, both with earlier approvals for generic versions of Maxzide, questioned the legality of Vitarine's exclusivity grant in separate complaints filed against FDA in November. The courts ruled in favor of FDA in both cases ("The Pink Sheet" Nov. 30, "In Brief"). In its approval letter to Vitarine, FDA noted that it had originally decided that Vitarine's exclusivity would only delay the effective dates of ANDA's "for formulations that were similar to Vitarine's in those respects covered by the patent on Maxzide." FDA changed its position, the letter notes, after considering arguments raised in a Sept. 3 letter from Vitarine's counsel, Alan Kaplan and Peter Mathers (D.C. law firm Kleinfeld, Kaplan & Becker). "FDA reached its final decision that the exclusivity must apply to all generic copies of the same listed drug on two grounds," the agency explained. "First, FDA agrees that the method FDA had proposed for determining whether a subsequent applicant benefited from the first applicant's judgment of noninfringement (looking to whether the patent holder also sued the subsequent applicant) would not, in fact, provide a reliable basis for determining whether the two applicants shared significant infringement issues," the agency stated. "Because FDA lacks the expertise in patent law that would allow it to reach such a determination in any other way, FDA concluded that it would be unable to implement its original interpretation." Secondly, FDA added, "the legislative history of section 505(j)(4)(B)(iv) is silent as to the purpose of the provision and does not limit its applicability to subsequent applicants that receive a benefit from the first applicant's finding of noninfringement; FDA agrees that obtaining a judgment of noninfringement provides a benefit to the public by overcoming an obstacle to competition." Thus, FDA concluded, "it is reasonable to provide a period of exclusive marketing to an applicant who successfully challenges a patent, regardless of the judgment's applicability to subsequent applicants."