Subsidiaries of generics maker Hetero Drugs can move forward with generic versions of kidney drug PhosLo despite an ongoing lawsuit brought by patent owner Roxane Laboratories.

A U.S. District Court in New Jersey denied a motion Aug. 6 from Roxane to block the generics as the case continues, finding that the patent infringement lawsuit has little chance of success. Nor would market entry by Hetero subsidiary Camber Pharmaceuticals disrupt a status quo, which already has several generic versions of PhosLo (calcium acetate) on the market, the judge ruled. Fellow litigant and Hetero subsidiary InvaGen Pharmaceuticals’ generic version is one of them.

Roxane, itself a generics maker, holds the patent rights on PhosLo’ active ingredient and markets its own generic version. Several other companies also market generic versions, the judge noted, meaning that Roxane’s claims of price erosion from further generic entry are unlikely.

The ruling also dealt the lawsuit’s future prospects a severe blow by finding many of Roxane’s infringement claims lacking, especially in noting that the PhosLo patent apparently covers a slightly different capsule size than the versions employed in Camber and InvaGen’s ANDAs. — Bryan Koenig

Originally appeared in Drug Industry Daily, the pharmaceutical industry’s number one source for regulatory news and information. Click here for more information.