Therapeutic depletion of myeloid lineage leukocytes by adsorptive apheresis for psoriatic arthritis: Efficacy of a non-drug intervention for patients refractory to pharmacologics.

Psoriatic arthritis (PsA), a chronic inflammatory arthropathy associated with psoriasis, is an intractable immune disorder and refractory to pharmacological intervention. We assessed efficacy of selective depletion of myeloid lineage leukocytes in patients with PsA in a multicenter setting. A total of 20 patients with moderate to severe PsA refractory to conventional and biological disease-modifying antirheumatic drugs were included. Eligible patients had 3 points or more in the classification criteria for PsA. Each patient received five sessions, once a week, of adsorptive granulocyte and monocyte apheresis (GMA) with the Adacolumn® . The primary efficacy outcome was 20% or more decrease in the American College of Rheumatology score 20 (ACR20). Partial responders could receive an additional five GMA sessions. Of 20 patients, two did not complete the study, nine responded to five GMA sessions and nine received 10 sessions. At the first evaluation 2 weeks after the last GMA session, 13 of the 20 (65.0%) patients achieved ACR20. ACR20 was maintained in seven of 10 (70%) and five of 10 (50%) patients at the follow-up evaluation points 8 and 20 weeks after the last GMA session, respectively. GMA was well tolerated without any safety concern. This study demonstrates that GMA with the Adacolumn was effective with good safety profile in patients with PsA refractory to pharmacologicals. The results indicate a major role for myeloid leukocytes in the immunopathogenesis of PsA. A large controlled study is warranted to fully evaluate the efficacy of Adacolumn GMA in patients with PsA.