Patients with moderate-to-severe plaque psoriasis who received treatment with guselkumab (Janssen), an investigational human monoclonal antibody directed specifically against IL-23, showed improvement of symptoms with no serious adverse events, findings from a phase II, dose-ranging study indicate.
Guselkumab reached the primary study endpoint, reducing physician global assessment (PGA) scores from ≥3 to either 0 or 1 after 16 weeks of treatment in 34.1%-87.5% patients compared with 7.1% in the placebo group and 58.1% of those in the adalimumab (Humira, AbbVie) arm.
Kristina Callis-Duffin, MD, University of Utah School of Medicine, Salt Lake City, and colleagues presented interim data from X-PLORE trial during the 2014 American Academy of Dermatology Annual Meeting.
A total of 293 participants with moderate-to-severe plaque psoriasis were randomly assigned to guselkumab, adaliumumab or placebo in the ongoing phase 2, randomized placebo- and active comparator-controlled seven-arm study.
Overall, 71% of participants were male with a median age of 45 years. Most patients (94%) continued on the study agent through the 16-week period.
Guselkumab dosages were as follows: 5 mg every 12 weeks (group 1); 15 mg every 8 weeks (group 2); 50 mg every 12 weeks (group 3); 100 mg every 8 weeks (group 4); and 200 mg every 12 weeks (group 5).
Psoriasis was defined by a Psoriasis Area and Severity Index (PASI) score greater than 12, physician global assessment (PGA) score greater than 3, and body surface area (BSA) involvement of at least 10%.
At the start of the study included, 54% of patients had PGA score of 3, median PASI score was 18.2 and median BSA involvement was 20%.
The proportion of patients by dosage group who reached the primary endpoint of a PGA of 0 or 1 at 16 weeks were as follows:
- Group 1: 34.1%
- Group 2: 61%
- Group 3: 78.6%
- Group 4: 85.7%
- Group 5: 83.3%
All groups reached clinically significant PGA improvements (P<0.001) compared with placebo, except the 5-mg arm (group 1; P=0.002).
In the adalimumab arm, 58.1% of participants reached the primary endpoint, as did 7.1% in the placebo arm.
The most common adverse events were infection (nasopharyngeal and upper respiratory), but no dose-response relationships were identified. Two patients in the 50-mg arm developed serious infections at week 16. Injection site reactions were highest in the adalimumab group at 6.6%, compared with 0.6% in the guselkumab arm and 0.6% in the placebo arm.
“Interim results from this ongoing phase 2 trial in patients with moderate-to-severe plaque psoriasis demonstrate a high level of efficacy with the guselkumab doses evaluated,” the researchers concluded.
Disclosure: This research was supported by Janssen Research & Development, LLC.