The Supreme Court said Tuesday that it will not hear a case brought by a generic pharmaceutical company that sought to invalidate a patent held by Pfizer Inc. for its blockbuster anti-depression drug Zoloft.

The case, brought by Winnipeg, Canada-based Apotex Inc., involved a controversial issue in the pharmaceutical industry: whether generic drug makers are sometimes blocked from issuing new products by brand-name companies that refuse to sue them for patent infringement during the FDA approval process.