FEMALE PSORIATIC ARTHRITIS PATIENTS SHOW DIFFERENCES IN TREATMENT RESPONSE TO IL12/23 INHIBITION IN COMBINATION WITH OR WITHOUT MTX COMPARED TO MALE – RESULTS FROM A MULTICENTER INVESTIGATOR-INITIATED RANDOMIZED PLACEBO-CONTROLLED CLINICAL TRIAL
Authors: Koehm M et al.
Baseline characteristics and clinical phenotypes may affect treatment responses. The results of this investigator-initiated, randomized and placebo-controlled trial (MUST trial) have been presented previously but are not yet fully published. This trial was designed to answer the question, whether MTX provides additional benefit in patients with active PsA when they receive ustekinumab. In brief, patients with active PsA with or without MTX were started on ustekinumab, an anti-IL12/23 directed monoclonal antibody and randomized to either use or not use MTX in combination. Using ustekinumab in monotherapy was non-inferior to ustekinumab in combination with MTX after 24 and 52 weeks with regard to arthritis, enthesitis, skin and dactylitis. The current subgroup analysis included 166 patients, 41.6% of these were female. Enthesitis was more frequent in females whereas dactylitis was more prominent in males. Differences were found between male and female patients: Female patients showed a decreased response with regard to resolution of pain, enthesitis, dactylitis and ACR response rates.
Baseline biomarkers that predict treatment responses are still missing. Unless contraindi-cations to specific treatment options are present, the choice between different biologics may largely depend on the rheumatologist’s preference and the presence or absence of skin involvement. Gender may represent another baseline characteristic that impacts response. The results from this analysis do not only show that treatment responses to ustekinumab do not depend on combination with MTX, but suggest that ustekinumab represents an inferior treatment option in female patients. However, the reason for this discrepancy between male and female patients remains unclear.