Shire has announced yet another “non-safety-related voluntary market withdrawal” in the USA of a number of its Daytrana attention deficit hyperactivity disorder patches.

The company said it is pulling 39 lots of Daytrana (methylphenidate) because some of the patches “no longer meet their release liner removal specification”. This means that patients could have difficulties taking off the protective liners on the product, which is manufactured by Shire partner Noven Pharmaceuticals.

The problem has been a recurring issue for the firms which initially pulled batches of Daytrana eighteen months ago and there have recalls of the product ever since. Shire insists that that this action is not due to safety issues and the current supply levels “should be sufficient to ensure that patients can continue to have their Daytrana prescriptions filled at their local pharmacy”.

Shire and Noven added that they “may implement additional voluntary actions. They also noted that they “continue to actively pursue enhancements to Daytrana” and are working with the US Food and Drug Administration to get an improved version on the market later this year.

Shire’s commitment to Daytrana in the USA is in marked contrast to the company’s plans for the patch in Europe. Last week, the company withdraw a submission to European regulators for Daytrana, after the latter had requested an additional clinical study. Shire noted that instead it will concentrate on promoting the instant- and extended-release versions of Equasym (methylphenidate), the ADHD drug it acquired the European rights to from UCB recently.

Fosrenol lawsuit extended to Mylan
Meantime, Shire also announced that it has filed a lawsuit in New York against Mylan claiming infringement of a patent on its kidney disease drug Fosrenol (lanthanum carbonate). Mylan has filed an Abbreviated New Drug Application to sell generic versions of the drug.

The suit comes days after Shire filed a similar case against Teva Pharmaceutical Industries. The company added that it has “a robust patent estate and is confident that it will protect the Fosrenol franchise”.