Japan's Ministry of Health, Labor and Welfare approved Ironwood Pharmaceuticals Inc.'s LINZESS for the treatment of adults with irritable bowel syndrome with constipation.
The approval triggers a $15 million milestone payment from development and commercialization partner Astellas Pharma Inc., which secured the marketing approval.
Under the agreement, Astellas paid Ironwood a $30 million upfront licensing fee, a $15 million development milestone payment upon enrollment of the first patient in a phase 3 trial, and a $15 million milestone payment upon the new drug application submission. The agreement also provides for Ironwood to receive royalties, which escalate based on sales volume.
Data from a phase 3 trial in Japan indicate that patients treated with 500 mcg of linaclotide showed statistically significant improvement compared to placebo-treated patients.
Another phase 3 trial of the drug in patients with chronic constipation is ongoing in Japan, with top-line data expected in 2017.
Astellas is expected to launch LINZESS in the first half of 2017.