Retrophin has agreed to purchase rights, titles, and ownership of a liquid formulation of ursodeoxycholic acid from Asklepion Pharmaceuticals for up to $59 million-plus.

Retrophin said yesterday it intends to file an NDA with the FDA next year for the liquid formulation of ursodeoxycholic acid for the treatment of primary biliary cholangitis (PBC).

“By commercializing a liquid formulation of ursodeoxycholic acid, we will aim to fill a gap in care for PBC patients who have difficulty swallowing pills,” Retrophin CEO Steve Aselage said in a statement. “Liquid ursodeoxycholic acid is highly complementary to our portfolio of bile acid therapies, allowing us to leverage our current commercial infrastructure and further diversify our marketed products.”

Retrophin agreed to pay Asklepion $0.5 million upfront as well as future payments of up to $23.5 million tied to achieving cumulative sales milestones of liquid ursodeoxycholic acid in PBC.

Asklepion will also be eligible for incremental milestone payments of up to $35 million upon successful development and commercialization, including cumulative sales milestones, of liquid ursodeoxycholic acid in additional indications.

Retrophin said it agreed to assume all future program costs and pay Asklepion tiered royalties on future product sales.

Retrophin has focused on rebuilding its specialty-drug portfolio in the nearly 2 years since its board ousted Martin Shkreli, then sued him in August for $65 million-plus, accusing him of breaching his duty of loyalty to the company, breaching his fiduciary duty, and unjust enrichment. Shkreli was arrested in December on Retrophin-related charges but has denied wrongdoing—and on June 6, he pleaded not guilty to an additional federal charge that he concealed control of Retrophin stock through employees and consultants.