Janssen reported positive data from a Phase III trial evaluating the interleukin 12 and interleukin 23 inhibitor Stelara® (ustekinumab) in patients with active psoriatic arthritis. The drug is currently only approved for treating plaque psoriasis in patients who are suitable for phototherapy or systemic therapy.
The placebo-controlled Psummit I study included 615 patients who had active psoriatic arthritis despite treatment with disease-modifying antirheumatic drugs and/or nonsteroidal anti-inflammatory drugs. The results showed that 42% of participants receiving 45 mg of Stelara, and 50% of patients treated using the 90 mg dose, achieved at least a 20% improvement in ACR criteria (ACR20) at week 24, compared with just 23% of placebo-treated patients. Stelara was dosed at weeks 0, 4, and then every 12 weeks. A significantly higher proportion of Stelara-treated patients also achieved ACR50 and ACR70 than those receiving placebo. The treatment in addition led to clinically relevant improvements in physical function, including enthesitis and dactylitis.
The Psummit 1 data also confirmed that treatment with Stelara was associated with significant improvements in EULAR/Disease Activity Score (DAS) 28 C-reactive protein responses. At week 24, 66% and 68% of patients receiving 45 mg and 90 mg of Stelara, respectively, reported EULAR/DAS-CRP response, compared with 34% of placebo patients. The drug was associated with marked improvements in plaque psoriasis, with up to 62% of patients on the high dose achieving at least a 75% improvement, compared with just 11% of placebo-treated patients.