Long-Term Benefits of Ixekizumab in Psoriatic Arthritis Save
The SPIRIT-P1 study has demonstrated the safety and efficacy of ixekizumab (an IL-17A antagonist) when given to adults w/ active psoriatic arthritis (PsA), and also demonstrating radiographic protection and improvement in skin outcomes as well.
This phase 3 study, enrolled biologic-naïve active PsA patients who randomly given either placebo, adalimumab 40 mg every 2 weeks (ADA) or ixekizumab 80 mg every 2 weeks (IXEQ2W) or every 4 weeks (IXEQ4W) after an initial dose of 160 mg. At week 16 or 24 ADA and placebo patients were re-randomized to IXEQ2W or IXEQ4W.
Of 417 patients, 381 entered the extension, and 243 of 381 (63.8%) completed the 156-week study.
Incidence rates of serious adverse events were 5.2 with IXEQ2W (n = 189) and 8.0 with IXEQ4W (n = 197). There was only one death (IXEQ4W group).
The week 156 response rates for IXEQ2W and IXEQ4W, respectively were:
- ACR20: 62.5 and 69.8%
- ACR50: 56.1 and 51.8%
- ACR70: 43.8 and 33.4%
- Psoriasis area and severity index (PASI) 75: 69.1 and 63.5%
- PASI 90: 64.5 and 51.2%
- PASI 100: 60.5 and 43.6%.
Inhibition of radiographic progression also persisted to week 156 in 61% of IXEQ2W and 71% of IXEQ4W patients.
The long term efficacy and safety of ixekizumab in PsA was observed, along with persistent low rates of radiographic progression.