ZURICH (Reuters) - Novartis AG plans to ask the U.S. Supreme court to uphold the validity of a patent it holds on the dosing regimen for multiple sclerosis drug Gilenya after suffering a setback in a federal appeals court ruling, the Swiss drugmaker said on Wednesday.

The ruling meant HEC Pharma and other drugmakers would potentially be able to launch a generic version of 0.5mg Gilenya imminently, pending any other judicial actions, it said.

"Should generics launch in the US, we expect FY 2022 sales to be negatively impacted by USD 0.3bn. With regard to 2022 Full Year Guidance for Group sales and core operating income growth, we continue to expect both in the mid-single digit range, in constant currencies," it added.

(Reporting by Michael Shields; Editing by Paul Carrel)