<p>Concerta is marketed by McNeil Consumer & Speciality Pharmaceuticals, a division of Johnson & Johnson, as a once-daily treatment for attention deficit disorder.<br /><br />Alza Corporation and McNeil filed the lawsuit last year after Impax submitted an application to market methylphenidate hydrocholoride ER tablets, a generic version of the drug Concerta. The lawsuit was voluntary dismissed after Alza and McNeil signed stipulation for the dismissal of the patent infringement.<br /><br />The drug application submitted by Impax remains under review by FDA as well as a citizen's petition filed by McNeil relating to approval criteria for Concerta generics.</p>