US-based healthcare company Ironwood Pharmaceuticals has revised its partnership agreement with AstraZeneca for the development and commercialisation of LINZESS (linaclotide) in China.

Following China’s National Medical Products Administration approval of LINZESS for adults with IBS-C, in January 2019, the company is planning to launch LINZESS in China in the second half of 2019.

Ironwood chief executive officer Mark Mallon said: “This amended collaboration combined with our recent amendment to our Astellas agreement reflects our continued strategy to focus our efforts in the U.S., thereby streamlining our business while enabling strong partners to bring linaclotide to patients worldwide.

“AstraZeneca has substantial experience and capabilities in developing and commercializing medicines in China. There are approximately 14 million adults suffering from IBS-C in China, and we believe AstraZeneca is well-positioned to bring LINZESS to these patients.”

The collaboration provides a total of up to £100m for Ironwood

Under the amended agreement terms, AstraZeneca is provided with exclusive rights to develop, manufacture and commercialise linaclotide in China, including Hong Kong and Macau, and is held responsible for all related expenses.

In exchange, Ironwood would receive a total of up to $125m (£100m), including non-contingent payments amounting $35m (£28m) paid in three instalments through 2024 and up to $90m (£72m) in commercial milestone payments contingent on the achievement of certain net sales targets.

Additionally, Ironwood would receive royalties starting from single-digit percentage and increasing up to 20% based on annual net sales of the drug in China.

Following the amended agreement, Ironwood would refrain from jointly funding the development and commercialization of linaclotide or sharing in the net profit from sales in China.

Linaclotide is used for the treatment of adults with IBS-C or chronic idiopathic constipation (CIC), and the product has been rolled out in the US and more than 30 other countries.

Ironwood said that it is focused on gastrointestinal (GI) diseases, and its partnership with AstraZeneca for linaclotide was established in 2012.