Aslan sells Japanese rights to would-be Dupixent rival for $12M

Zenyaku Kogyo is lining up a challenge to Sanofi and Regeneron’s blockbuster Dupixent in Japan, paying Aslan Pharmaceuticals $12 million upfront for local rights to a midphase eczema drug candidate. 

Aslan sees its anti-IL-13 receptor antibody eblasakimab as the molecule to address the unmet needs that Dupixent has failed to address. With its market cap languishing at $64 million, Aslan is yet to convince investors it is on to a winner but the Singapore-based company has persuaded Zenyaku to write a check and add its candidate to a Japanese portfolio that features products including Rituxan.

Zenyaku is paying $12 million upfront for the rights to develop and commercialize eblasakimab in atopic dermatitis, the most common form of eczema, and all other indications in Japan. Aslan will receive $3 million more if it meets pre-agreed conditions related to a phase 2b trial.

The conditions cover the data readout and delivery of the clinical study report, and the milestone marks the start of a potential series of escalating paydays for Aslan. Overall, Zenyaku is on the hook for up to $29.5 million in development milestones and up to $94 million in commercial milestones.

In return for the outlay, the Japanese drugmaker will gain regional rights to a molecule that is designed to prevent signaling through IL-4 and IL-13. Aslan thinks (PDF) its approach could more efficiently block IL-13 signaling than Dupixent, and thereby potentially have improved dose frequency and efficacy. With only a subset of patients having optimal responses to Dupixent, there is scope to improve on the drug.

Whether eblasakimab can seize the opportunity created by the limitations of Dupixent remains to be seen. Aslan expects to have topline data from a phase 2b clinical trial of its antibody in biologic-naïve atopic dermatitis patients early next month. Midphase data in patients previously treated with Dupixent are due in the first quarter of next year.

Zenyaku plans to start a phase 1 trial of eblasakimab in Japan in the first half of next year. Aslan has kept an option to re-acquire the rights to its IL-13 antibody in Japan at any time.