AstraZeneca and Ironwood have teamed up to get the world’s first drug for irritable bowel syndrome onto the Chinese market.

The two firms have agreed to co-develop and co-commercialise Ironwood’s Linzess (linaclotide) in China. The drug is the first and only guanylate cyclase-C agonist approved by the FDA for irritable bowel syndrome with constipation and chronic idiopathic constipation. The drug was approved in the US in August, and is expected to be launched by the end of the year.

Under the terms of the collaboration, AstraZeneca will make an upfront payment of $25 million to Ironwood and will share the net profits and losses associated with Linzess in China, with AstraZeneca carrying 55% of each until a certain specified milestone is achieved, moving to a 50/50 split thereafter.

Ironwood will also be eligible for $125 million in additional commercial milestone payments contingent on the achievement of certain sales targets.

IBS, which is characterised by symptoms of abdominal pain and constipation, is a chronic and prevalent functional gastrointestinal disorder in China and there are currently few treatment options for this condition, according to AZ.

By going to China, both firms will hope to open up the drug to a population of over 1.3 billion people. AZ already has a strong operational showing in the region, and can help Ironwood boost its sales and marketing potential in the country.

“China is one of the fastest growing prescription medicines markets in the world and linaclotide represents a valuable opportunity to meet the needs of local patients by providing an innovative new treatment option,” said Mark Mallon, regional VP for Asia Pacific and president of AstraZeneca China.

“We are pleased to be collaborating with Ironwood for linaclotide in China, which capitalises on our leadership in the gastrointestinal sector in the emerging markets.”

Peter Hecht, Ironwood’s chief executive, added: “As we continue to advance our efforts to make linaclotide available to patients around the world, we are excited about this opportunity to collaborate in China with AstraZeneca, one of the world’s most successful companies in gastrointestinal medicine.”

Analysts believe that Linzess is going to be a blockbuster principally because of the pain relief it offers. Developed by Ironwood and Forest Laboratories, it also licensed to Almirall in Europe and to Astellas in parts of Asia.

Nexium deal

In addition, the companies also announced that around 160 of Ironwood’s clinical sales specialists will promote AstraZeneca’s gastroesophageal reflux disease drug Nexium (esomeprazole magnesium) in the US.

In return, the deal allows Ironwood with an opportunity to increase its presence with gastrointestinal physicians in the country, with an eye on the imminent launch of Linzess.