Amgen and Kyowa Kirin have signed an agreement to jointly develop and commercialise KHK4083, a monoclonal antibody (mAb) in development for the treatment of atopic dermatitis – the most common form of eczema.

As part of the agreement, Amgen will take the lead on the development, manufacturing and commercialisation of KHK4083 for all markets globally, excluding Japan where Kyowa Kirin will retain all rights.

Kyowa Kirin will also co-promote the mAb with Amgen in the US and have opt-in rights to co-promote KHK4083 in certain other markets, including Europe and Asia.

In return, Amgen will pay Kyowa Kirin $400m upfront and future contingent milestone payments potentially worth up to an additional $850m, as well as ‘significant’ royalty payments on future global sales.

KHK4083 is an anti-OX40 fully human mAb engineered using Kyowa Kirin’s POTELLIGENT defucosylation technology, used to enhance its antibody-dependent cellular cytotoxicity (ADCC) activity.

In February, KHK4083 met the primary endpoint in a Phase II trial including 274 patients with moderate-to-severe atopic dermatitis who were not adequately controlled with topical agents.

All KYK4083-treated cohorts achieved superiority to the placebo cohort for the primary endpoint of percent change from baseline in the Eczema Area and Severity Index (EASI) at 16 weeks with statistical difference.

There was also a significant difference in the percentage of KYK4083-treated patients achieving EASI-75 (EASI score of 75% or greater improvement from baseline) at 16 weeks.

In addition, more patients who received the mAb achieved the Investigator’s Global Assessment (IGA) of 0 or 1 with an improvement of 2 points or more at 16 weeks.

"Kyowa Kirin was one of Amgen's very first collaborators and we are delighted to be joining forces with them once again to advance this promising late-stage asset to treat atopic dermatitis," said Robert Bradway, chairman and chief executive officer at Amgen.

"We will take advantage of our two decades of experience in inflammatory disease, as well as our industry-leading human genetics capabilities, to help realise the full potential of KHK4083 as quickly as possible,” he added.