Ixekizumab is a new IL-17A antibody that was recently approved by the FDA for the management of psoriasis and PsA. It’s the second IL-17A blocker that will be available for the management of psoriasis and PsA.
At the last ACR meeting, safety and efficacy of ixekizumab (IXE) was demonstrated and the response rates were numerically similar to adalimumab (direct comparison) with regard to ACR and PASI responses.
Today at EULAR, 52-week results from the Phase 3 study (SPIRIT-P1) were presented by Dr. Mease (#OP0109). This RCT had a complicated study design and included biologic-naïve patients (as opposed to the FUTURE 1 and 2 trials with secukinumab that included a proportion of patients exposed to TNFi).
A total of 417 patients with active PsA were randomized 1:1:1:1 to IXE 80 mg Q4W or Q2W including a 160 mg starting dose, to 40 mg adalimumab (ADA), or to PBO (all subcutaneous dosing) during weeks 0 to 24. Of these, 381 patients entered the extension period from weeks 24 to 52, where they were assigned to 80 mg IXE Q4W or Q2W.
Patients randomized to IXE at week 0 continued the same dose regimen in the extension period. Patients randomized to PBO or ADA at week 0 were re-randomized (1:1) to 80 mg IXE Q4W or Q2W at week 16 (inadequate responders) or 24. Those patients who initially received PBO started IXE at week 16 or 24; patients who initially received ADA started IXE at week 24 or 32 after an 8-week wash-out period.
At 52 weeks, the ACR20/50/70 responses were around 66/50/34 for both IXE doses, respectively. PASI 100 was around 50%. Significant improvement in enthesitis and dactylitis was reported. 12 SAEs occurred in 12 patients. There were no deaths.
This study confirms the efficacy and safety of ixekizumab over a 1-year period. The efficacy in TNFi exposed patients remains to be determined.
Dr. Chandran is a rheumatologist and clinician-scientist, an Assistant Professor of Medicine & Laboratory Medicine and Pathobiology at the University of Toronto, an affiliate scientist at the Krembil Research Institute, a staff physician at the University Health Network and Mount Sinai Hospitals, and an associate member of the graduate faculty at the Institute of Medical Science. He co-directs the Psoriatic Arthritis Program at the University Health Network.View Full Bio