Shire has settled all litigation with Impax Laboratories concerning a dispute over a generic version of the attention-deficit hyperactivity disorder drug Adderall XR.

Shire has been supplying Impax with authorised generic Adderall XR (mixed amphetamine salts) since October 2009 but a year later the former filed suit claiming a breach of supply obligations. Shire responded with a counterclaim relating to Impax' ordering practices under the agreement.

Now the two suits have been dismissed and the companies have entered into an amended agreement up until the end of the supply term, September 30, 2014. As part of the settlement, Shire will make a one-time cash payment to Impax of $48.0 million.

As well as Impax, Teva has been selling an authorised generic version of Adderall and last June, the US Food and Drug Administration gave the green light to Actavis' copy. Impax added that it will continue to pursue approval for its own generic of the drug which was filed with the agency in September 2003.

The settlement comes a couple of weeks after Shire reached an agreement with the US government to resolve a civil investigation into US sales and marketing practices relating to Adderall XR, Vyvanse (lisdexamfetamine dimesylate) and the ADHD patch Daytrana (methylphenidate).

Shire has recorded a $57.5 million charge for the fourth quarter of 2012 to cover the settlement, plus interest and costs. The agreement also addresses the firm's marketing practices regarding the ulcerative colitis drug Lialda and Pentasa (both mesalamine).

Phase III trial for rare skin disorder

Meantime, Shire has started a Phase III study designed to evaluate the efficacy and safety of ABH001, its dermal substitute therapy, for the treatment of non-healing wounds in patients with epidermolysis bullosa. The latter is a group of rare genetic skin disorders that occur in 19 per one million live births in the USA.

Some 20 subjects with generalised EB aged three years and older are planned to enrol the trial. ABH001 is currently marketed in the USA under the tradename Dermagraft for the treatment of diabetic foot ulcers.

Shire is also developing an intravenous protein replacement therapy for dystrophic EB, which the company’s Human Genetic Therapies business recently acquired from Lotus Tissue Repair.