Johnson & Johnson announced that TREMFYA® (guselkumab) has achieved significant clinical milestones in the treatment of active psoriatic arthritis (PsA), becoming the first and only IL-23 inhibitor to demonstrate reduction in both disease symptoms and structural damage progression.
Breakthrough Results in Phase 3b APEX Study
The Phase 3b APEX study met both its primary endpoint of reducing signs and symptoms (ACR20) and its major secondary endpoint of reducing progression of structural damage at 24 weeks in adults with active psoriatic arthritis, compared to placebo.
TREMFYA-treated patients exhibited significantly less progression of structural damage versus placebo recipients as assessed by the PsA modified van der Heijde-Sharp (vdH-S) score, which measures joint space narrowing and erosion. This achievement marks a significant advancement in the management of PsA, a chronic inflammatory disease that can cause irreversible joint damage if left untreated.
"Psoriatic arthritis can be a progressive and debilitating disease, and without early identification and treatment, patients may experience irreversible joint damage that significantly impacts their daily activities," said Terence Rooney, Vice President, Rheumatology Disease Area Leader at Johnson & Johnson Innovative Medicine. "These new topline data highlight the importance of addressing both inflammation and structural damage at the source as early as possible."
Unique Mechanism of Action
TREMFYA is distinguished by its dual-acting mechanism as the first fully-human monoclonal antibody approved for PsA that blocks interleukin-23 (IL-23) while also binding to CD64, a receptor on cells that produce IL-23. This cytokine is a known driver of immune-mediated diseases including active psoriatic arthritis.
The antibody was originally developed using MorphoSys' antibody technology platform. Johnson & Johnson now maintains exclusive worldwide marketing rights to TREMFYA following a series of business transactions that saw MorphoSys sell its royalty rights to Royalty Pharma, which subsequently sold the remaining rights to an undisclosed buyer believed to be Johnson & Johnson.
Study Design and Patient Population
The APEX trial specifically enrolled biologic-naïve patients who had inadequate responses to standard therapies such as conventional synthetic disease-modifying antirheumatic drugs (csDMARDs), apremilast, or nonsteroidal anti-inflammatory drugs (NSAIDs).
The study design includes a 24-week double-blind, placebo-controlled period, followed by a 24-week active treatment period and a 12-week safety follow-up. For patients entering the long-term extension, an additional two years of active treatment is scheduled before final safety assessment.
Expanding Treatment Portfolio
TREMFYA is already approved for multiple indications including:
- Moderate to severe plaque psoriasis in adults
- Active psoriatic arthritis in adults
- Moderately to severely active ulcerative colitis in adults
- Moderately to severely active Crohn's disease in adults
The drug has previously demonstrated efficacy in Crohn's disease, where it outperformed Stelara in endoscopic endpoints during earlier clinical trials.
Safety Profile
Data from the APEX study were consistent with TREMFYA's well-established safety profile, with no new safety signals identified. This reinforces the medication's position as a valuable treatment option for patients with active PsA.
Clinical Implications
Psoriatic arthritis affects approximately 30% of people with plaque psoriasis and is characterized by joint inflammation, enthesitis, dactylitis, axial disease, and skin lesions. The condition typically appears between ages 30 and 50, causing pain, stiffness, and swelling in and around joints.
Nearly half of PsA patients experience moderate fatigue, and about one-third suffer from severe fatigue. Comorbidities such as obesity, cardiovascular disease, anxiety, and depression are common among these patients.
The ability to address both symptomatic relief and structural damage progression positions TREMFYA as a potentially first-line treatment option for appropriate patients with active PsA.
Johnson & Johnson plans to present detailed results from the APEX study at upcoming medical congresses, which will provide further insights into TREMFYA's efficacy profile and long-term benefits for patients with psoriatic arthritis.
