Harris KM, Smilek DE, Byron M, et al. - Findings revealed failure of abatacept in preventing psoriasis relapse that occurred after ustekinumab withdrawal. This inability to prevent relapse was due to failure to completely block the pathogenic psoriasis molecular pathways that resulted in relapse.

• This is a parallel-design, double-blind randomized clinical trial of 91 adults with moderate to severe plaque psoriasis who were randomized to the abatacept group or to the ustekinumab group.

• Relapse between weeks 12 and 88 occurred in similar proportions of participants in the abatacept group and the ustekinumab group (91.1% vs 87.0%).

• The median time to relapse from the last dose of ustekinumab was found to be similar between groups (36 weeks in the abatacept group vs 32 weeks in the ustekinumab group).

• The numbers and rates of adverse events were also similar between the groups.

• Abatacept failed to maintain suppression of the pathogenic interkeukin (IL)-23-mediated psoriasis molecular signature in lesions following withdrawal of ustekinumab, and serum IL-19 levels raised.