Amgen’s $400 million bet on Kyowa Kirin’s atopic dermatitis drug has hit a bump in the road. Weeks after starting a 570-subject phase 3 clinical trial, the partners have paused (PDF) patient enrollment to make changes to the study that are unrelated to safety or efficacy.
The ROCKET-IGNITE study got underway on May 31 to compare the effects of 52 weeks of injections of the anti-OX40 monoclonal antibody AMG 451, also known as KHK4083 and rocatinlimab, to placebo in adults with moderate to severe atopic dermatitis. Amgen is studying four subcutaneous regimens of the drug in the clinical trial.
However, on Thursday, 66 days after the trial began, Kyowa revealed the partners have paused the study. The Japanese drugmaker provided a brief explanation for the U-turn in its financial results for the second quarter.
“Following additional discussions with regulators and our partner, we are amending the studies to improve patient convenience and investigate a range of doses. No safety or efficacy issues have arisen,” Kyowa said.
Amgen paid Kyowa $400 million upfront and committed up to $850 million in milestones to lead work on AMG 451 outside of Japan last summer. In October, researchers released data from a phase 2 trial of 274 adults, linking 16 weeks of treatment with the antibody to reductions on an eczema scale of 48% to 61%.
The pause is a temporary setback to Amgen’s bid to establish AMG 451 as a first-in-class treatment for atopic dermatitis, an indication that has attracted a clutch of companies with aspirations to dethrone Sanofi and Regeneron’s Dupixent. If Amgen is right, hitting OX40 will deplete activated T cells to improve outcomes in patients with the skin condition.
Amgen changed the status of the study on ClinicalTrials.gov to “active, not recruiting” last month. The listing still puts the estimated primary completion at March 2024.