Risankizumab Significantly More Effective Than Placebo in Treating Psoriatic Arthritis

Risankizumab (RZB) showed significantly greater improvements in symptoms of psoriatic arthritis (PsA) when compared with a placebo, according to a study presented at the EULAR Virtual Congress 2021, entitled, “Efficacy and Safety of Risankizumab for Active Psoriatic Arthritis, Includintg Patients With Inadequate Response or Intolerance to Biologic Therapies: 24-Week Results From the Phase 3, Randomized, Double-blind, KEEPsAKE 2 Trail.” RZB was also well tolerated in patients who were intolerant to biologics (Bio-IR) and conventional synthetic disease-modifying antirheumatic drugs (csDMARDs-IR).

RZB is an immunoglobulin G1 monoclonal antibody that binds to the p19 subunit of interleukin 23 (IL-23) and works by selectively inhibiting this cytokine. The KEEPsAKE 2 trail compared RZB with a placebo in patients with active PsA who have a history of inadequate response and/or intolerance to biologics and DMARD therapies.

Patients were randomized and received subcutaneous RZB 150 mg at week 0, 4 and 16 or a placebo. The primary endpoint was achieving an American College of Rheumatology score of ≥ 20% improvement (ACR20) at the end of week 24. Safety was also a top priority.

Eligible patients were aged ≥ 18 years and had active psoriatic arthritis (PsA) as defined by having symptom onset for ≥ 6 months, ≥ 5 tender and swollen joints, active plaque psoriasis, and meeting Classification Criteria for Psoriatic Arthritis (CASPAR) standards. Additionally, participants demonstrated inadequate response or intolerance to 1 or 2 eligible biologic agents or conventional synthetic disease-modifying antirheumatic drugs (csDMARDs), including methotrexate, apremilast, and sulfasalazine.

Of the 443 patients, 224 were selected for the RZB cohort and 219 received the placebo. Participants had similar demographics and baseline characteristics in both RZB and placebo cohorts. The majority were female (55.4% and 54.8%, respectively) and of comparable age (53 years and 52 years, respectively). The mean swollen joint count was 13.3, tender joint count was 22.6, and the mean duration of PsA was 8.2 years. A total of 206 patients had inadequate response to biologic therapies.

Significantly more patients in the RZB cohort achieved the primary endpoint when compared with the placebo group (51.3% vs 26.5%, respectively; P < .001), including disease activity in joints and skin for patients who were Bio-IR and csDMARD-IR. Serious adverse events were reported for 4.0% of participants in the RZB group, compared with 5.5% in the placebo group. Apart from the Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-Fatigue; P < .009), RZB-treated patients showed improvement in all secondary endpoints as well.

The RZB group did not exhibit any specific safety issues and had similar adverse effects when compared to the placebo group. There were no deaths reported in either arms.

“When we look at the ranked and non-ranked secondary endpoints, all of these were met with a statistically significant superiority of RZB over placebo, including patient-reported outcomes (PROs) as well as enthesitis and dactylitis scores,” stated Andrew Östör, MD, MA, MB, FRACP, FRCP.