Mallinckrodt Public Ltd. Co. reached a settlement with the U.S. Federal Trade Commission to resolve the latter's investigation into Questcor Pharmaceuticals Inc.'s acquisition of Synacthen Depot in 2013.

The product, a synthetic adrenocorticotropic hormone used outside the U.S. as treatment for a number of conditions, became part of Mallinckrodt's portfolio with its August 2014 acquisition of Questcor.

Mallinckrodt did not admit any wrongdoing, but agreed to pay $100 million to settle claims made by the FTC and the states of Alaska, Maryland, New York, Texas, and Washington that it engaged in anticompetitive conduct.

The company will pay $90 million within 10 business days, $10 million within 90 days, plus $2 million to reimburse the states' legal fees.

Under the agreement, the company will license the drug to Marathon Pharmaceuticals LLC, to develop and pursue possible U.S. FDA approval of Synacthen Depot in two indications: infantile spasms and nephrotic syndrome. Marathon will also acquire exclusive rights to the Synacthen trademark in the U.S.

Mallinckrodt said the deal "[removes] the distraction of litigation," allowing the company to develop the product for all other indications in the U.S. except IS and NS, including potential use as treatment for patients with Duchenne muscular dystrophy.

Mallinckrodt said it does not derive any U.S. revenue from Synacthen Depot, which is not FDA-approved for use in the U.S., and that the settlement will not impact the company's net sales.