Sun Pharma agree settlement in US court over IBS drug

An agreement has been reached between pharmaceutical companies Ironwood Pharmaceuticals LTD, Allergan PLC and wholly-owned subsidiaries of Indian multinational Sun Pharmaceutical Industries Ltd over its application to market a new generic version of the drug LINZESS (Linaclotide) before its patents have expired.

The full details of the settlement have not been disclosed, but the result is that Ironwood Pharmaceuticals LTD and Allergan PLC will grant Sun Pharma and its subsidiaries a license to market the generic drug in the United States from 2031 – subject to its approval by the US FDA. The drug is an important revenue stream for Ironwood, whose sales of the branded version reached $700m in December 2017, and made up 75% of the company’s total sales.

The drug Linaclotide is marketed in the US under the brand dame LINZESS by Ironwood and Allergan, and is used in the treatment of patients with irritable bowel syndrome, constipation or chronic idiopathic constipation. It is in widespread use, being prescribed to 1.5 million Americans currently, and with over 9 million prescriptions since its launch. It is also marketed in Europe under the name CONSTELLA®, where Ironwood partner with Astella to sell the drug.

The settlement is good news for Sun Pharma, the world’s fourth-largest generic pharmaceuticals company, after a string of bad results over the last two years have seen its profits decline. This decision will allow it to enter the market early, ahead of other drug companies also seeking to market generic versions of LINZESS in the US, who are scheduled to go to court over the next few years. The first of these trial dates is set for June 2019, giving Sun Pharma a year’s head start. This news has seen Sun Pharma’s stock value shoot up by 1%.

Tom McCourt, Chief Commercial Officer at Ironwood, said: “Ironwood and Allergan have established Linzess as the branded prescription market leader in the IBS-C and CIC category. We are pleased to have resolved this patent litigation with Sun Pharma, as we believe it confirms the strength of our Linzess intellectual property. Allergan and Ironwood are committed to continuing to grow the Linzess franchise for many years to come.”



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