At the request of Telios Pharmaceuticals Inc., the U.S. Patentand Trademark Office (PTO) last week declared an interferencebetween a U.S. patent application on RGD peptides filed by theLa Jolla Cancer Research Foundation (and licensed exclusivelyto Telios) and a U.S. patent assigned to Merck & Co. Inc.

The PTO also included in the interference a patent applicationsubmitted by researchers affiliated with SmithKline Beechamand another submitted by Asahi Glass Co. of Japan

All the parties are claiming inventions related to cyclicpeptides containing the amino acid sequence arginine-glycine-aspartic acid (RGD) and its derivitives. These amino acidsapparently constitute a cell adhesion sequence, and as suchmediate cell interactions. Thus, peptides containing the RGDsequence could be used as therapeutics for diseases that resultfrom unwelcome interactions between cells and theextracellular matrix.

Patents covering RGD peptides are core to Telios' businessplans. In fact, the San Diego company was formed in 1987 toexplore the commercial potential of broad composition-of-matter patents already issued to the La Jolla Cancer ResearchFoundation, explained Audrey Keane, Telios' director ofcorporate development.

The foundation owns seven issued patents; its pendingapplication on cyclic RGD peptides and derivatives is the basisof the interference declaration.

The purpose of an interference proceeding is to determinewhich of the parties claiming the patentable material isactually the inventor and entitled to the exclusive patentrights.

With a filing date of December 1987, the foundation'sapplication was first, according to the PTO, making it the seniorparty in the upcoming proceedings. All the other companies arejunior parties.

For instance, Merck & Co. filed its application on cyclic RGDpeptides in July 1989 and the patent issued in June 1991;SmithKline Beecham filed its application in April 1989; andAsahi submitted an application in Japan in March 1989 and inMay 1990 filed in the U.S., Keane said.

The junior parties now have until Feb. 15, 1994, to respond tothe PTO with a preliminary statement, explained Keane. Itmight take several years for the PTO to decide the matter.

Meanwhile, Telios has several of its RGD-based pharmaceuticalsin advanced stages of development. In March the companysubmitted a premarket approval application (PMA) to FDA forthe use of Argidene Gel (which contains RGD in a hyaluronicacid gel) in the treatment of diabetic foot ulcers. In Septemberthe company started a multicenter Phase II clinical trial of itsOcuNex ophthalmic solution, which contains RGD attached tochondroitin sulfate, for treating severe dry eye associated withocular surface disease.

And earlier this month Telios filed an investigational new drugapplication (IND) with the FDA for its platelet aggregationinhibitor TP-9201 (which consists of a cyclic peptide containingRGD).

-- Jennifer Van Brunt Senior Editor

(c) 1997 American Health Consultants. All rights reserved.