Guselkumab, an IL-23 Inhibitor, Effective in Psoriatic Arthritis Save

The DISCOVER‐2 trial has shown that guselkumab, an interleukin‐23p19 was shown to be safe and effective in biologic‐naïve psoriatic arthritis (PsA) patients in a one year study.

This was a phase III trial that enrolled  biologic‐naïve PsA patients with active disease (≥5 swollen+≥5 tender joints; CRP ≥0.6mg/dL) despite prior ineffective DMARD treatment. Patients were randomized to receive either subcutaneous injections of guselkumab (GUS) 100mg every‐4‐weeks (Q4W); guselkumab 100mg at Week0, Week4, Q8W; or placebo with crossover to guselkumab 100mg Q4W at Week24. 

A total of 739 patients were randomized, and 93% completed through Week52. ACR20 response rates at week 24 were:

• GUS q4 wk - 64%
• GUS q8 wk - 64%
• Placebo - 33% (both p<0.0001)

After week 24, placebo patients were crossed over to GUS 100 mg q4wk and ACR20 responses were maintained out to week 52 (71% and 75%, respectively).

Similarly, other secondary endpoint outcomes were significantly improved in GUS treated patients (ACR50/ACR70 and skin responses, minimal or very low disease activity) through Week 52.  

Week 52 resolution of dactylitis was seen in 75% of GUS treated patients and 58% had resolution of enthesitis.

There were no deaths or opportunistic infections in the trial. Serious infections occured in 1.2% of GUS treated patients (SIE 1.49/100 PY).

Guselkumab was effective in PsA patients with improvements in multiple domains over a 52 week study.