Ista Pharmaceuticals' market exclusivity for Vitrase (hyaluronidase for injection; lyophilized, ovine) has been extended from three years to five years by US FDA for use as a spreading agent to facilitate the dispersion and absorption of other drugs. Ista's US market exclusivity now extends until May 5, 2009.

Ista has been further informed that Vitrase is entitled to five-year new chemical entity exclusivity pursuant to various sections of the Federal Food, Drug and Cosmetic Act and 21 CFR 314.108(b). ISTA had been informed earlier that it had received three years of new clinical investigation exclusivity. However, after reviewing information and data regarding hyaluronidase drug products, which are protein molecules that have not been fully characterized, the FDA decided that five-year exclusivity would be appropriate because there was inadequate information to determine whether any moiety in Vitrase is the same as any previously approved moiety.

The FDA letter also indicated that new chemical entity exclusivity is a bar to submission of certain 505(b)(2) applications and ANDAs. Finally, the letter said that new chemical entity exclusivity is not a prohibition on review and approval of any 505(b)(2) application or ANDA that was submitted to the agency before the Vitrase was granted five-year exclusivity, release from Ista said here.

Vicente Anido, president and CEO of ISTA, stated, "We are in discussions with the FDA to understand the change in Vitrase's exclusivity."

Ista's Vitrase is a proprietary formulation of highly purified ovine hyaluronidase. In May 2004, the FDA approved Vitrase in a 6,200 USP Units multi-purpose vial, for use as a spreading agent to facilitate the absorption and dispersion of other injected drugs. In August 2004, ISTA filed a supplemental New Drug Application (sNDA) for a smaller, single-use, 150 USP Units/mL vial of Vitrase that the Company believes will be more convenient and cost effective for use as a spreading agent. Pending timely FDA review and approval, Ista plans to launch this new vial size in early 2005.