SHIRE, the Irish-headquartered drugs company, has rebuffed claims by a US hedge fund that it does not have grounds to maintain patents on two of its key medications.
The patents relate to Lialda, a drug that treats ulcerative colitis, a bowl disease, and Gattex, which is used in the treatment of short bowel syndrome. Together the drugs made up approximately 12pc of Shire's revenue in 2014.
The patents have been challenged by Kyle Bass, the founder of Dallas-based hedge fund Hayman Capital Management.
Mr Bass had pledged to challenge patents on numerous medications, accusing drugmakers of misusing the patent system to keep drug prices high and low-cost copies away from customers.
Hayman Capital Management, the fund that Mr Bass founded, claimed that a "small minority" of drug companies "are abusing the patent system to sustain invalid patents that contain no meaningful innovations but serve to maintain their anti-competitive, high-price monopoly".
A statement from Shire hit back, saying that the patents for the two drugs "protect the innovation and value Shire brings to patients who benefit from these important medicines".
It added: "Shire will continue to defend vigorously its patents and pursue all legal options available to protect its products."
Shire moved its headquarters to Ireland in 2008. It emerged in February that the company may be subject to a bill of almost €480m relating to a $1.65bn break fee it got after a merger with Chicago-based AbbVie fell through. Tax advisers to Shire have told the firm that it is not taxable here although this position has not yet been agreed with Revenue.