Guselkumab Sustained Long-Term Efficacy in Patients with Active Psoriatic Arthritis

March 18, 2021
Lana Dykes

Guselkumab is the first and only approved IL-23 inhibitor therapy used to treat adults with active PsA and moderate to severe plaque psoriasis (PsO). The medication showed efficacy in skin clearance and joint symptom relief and passed safety measures. Additionally, physical function, health-related quality of life, and resolution of enthesitis and dactylitis were confirmed through week 100.

The results from a Phase 3 DISCOVER-2 study performed by the Janssen Pharmaceutical Companies of Johnson & Johnson indicate that guselkumab (TREMFYA) was effective in treating adult patients with psoriatic arthritis (PsA) through 2 years (week 112). Guselkumab is the first and only approved IL-23 inhibitor therapy used to treat adults with active PsA and moderate to severe plaque psoriasis (PsO). The medication showed efficacy in skin clearance and joint symptom relief and passed safety measures. Additionally, physical function, health-related quality of life, and resolution of enthesitis and dactylitis were confirmed through week 100.

"PsA is a chronic inflammatory disease of the skin, joints, and soft tissue and therefore, sustained control of this inflammation is important to physicians and patients," stated Alyssa Johnsen, M.D., Ph.D., Vice President, Rheumatology Disease Area Leader, Janssen Research & Development, LLC. "These long-term study results further bolster our confidence in the ability of TREMFYA to significantly improve the diverse manifestations of PsA over time.”

The medication works by selectively binding to the p19 subunit of IL-23, inhibiting interaction with the IL-23 receptor. IL-23 is a cytokine that is known to increase the inflammatory immune response associated with PsA, PsO, and other autoimmune diseases. Guselkumab was approved based on previous DISCOVER-1 and DISCOVER-2 studies that showed it was effective at helping patients reach the primary endpoint of ACR 20 response at both 24 and 52 weeks.

In patients with skin involvement at baseline, patients receiving guselkumab every 4 (q4w) and 8 (q8w) weeks had 59% and 53% complete skin clearance (Psoriasis Area Severity Index [PASI] 100), respectively. Additionally, 76% of patients receiving the medication every 4 weeks and 74% of patients receiving it every 8 weeks had a 20% improvement in joint symptoms (ACR 20). The radiographic progression for the 2-year period was also measured. At the 24-week mark, the medication showed significant inhibition of joint structural damage (p=0.011) in the q4w cohort and less radiographic progression in the q8w group, when compared with a placebo. From week 52 through 100, progression of joint damage was low for both groups, further reducing rates observed from the first 52 weeks. A group of patients switched from a placebo to q4w at week 24, and scores went from 1.12 (0-24 weeks), 0.34 (24-52 weeks), and 0.13 (52-100 weeks). For patients with PsO, 62% of q4w patients and 55% of q8w patients had complete skin clearance according to the Investigator Global Assessment (IGA) score of 0. Approximately 90% of patients were able to continue treatment through week 100.

Throughout the 112-week study, no new safety signals were observed and the long-term treatment for 2 years was comparable with the safety at 6 months and 1 year for both patients with PsA and moderate to severe plaque PsO.

"PsA can be a chronically painful and debilitating disease, and many PsA patients are still searching for enduring relief of their symptoms," explained Philip J. Mease,e M.D. "These data, which show that the observed benefits of TREMFYA in PsA continue through two years, represent positive news for physicians and patients alike."