TREMFYA– Treatment of Adult Patients with Psoriatic Arthritis and Axial Involvement – Real-World Evidence

SUMMARY  

• The company cannot recommend any practices, procedures, or usage that deviate from the approved labeling.
• A prospective, single-center, longitudinal, observational cohort study assessed the treatment of TREMFYA in adult patients with psoriatic arthritis (PsA). The cohort included patients with axial involvement.¹ 
• A prospective, multicenter cohort study evaluated the effectiveness of TREMFYA in adult patients with PsA and suggestive features of axial involvement.² 
• A retrospective multicenter observational study assessed the risk factors with response to TREMFYA or risankizumab in adult patients with axial and/or mixed PsA in a real-world clinical setting. Results are summarized for patients receiving TREMFYA.³ 
• Results are included below for these real-world studies.^1-3

CLINICAL DATA

Prospective Studies

Foti et al (2025)¹ conducted a prospective, single-center, 12-month, longitudinal, observational cohort study in a real-world setting to assess the treatment of TREMFYA in adult patients with PsA. Among the cohort of patients with PsA, patients presenting with axial involvement were included in this study.

Study Design/Methods

• All patients with PsA met the ClASsification Criteria for Psoriatic Arthritis (CASPAR) at screening.
• Axial involvement was characterized by:
  • Inflammatory back pain meeting the Assessment of SpondyloArthritis International Society (ASAS) criteria.
  • Confirmed by sacroiliac joint magnetic resistance imaging (MRI) which demonstrated active bone marrow edema consistent with inflammatory sacroiliitis (measured using the SPondyloArthritis Research Consortium of Canada [SPARCC] scoring method).
• Patients received TREMFYA 100 mg by subcutaneous (SC) injection at week 0, week 4, and every 8 weeks (q8w) thereafter.
• Primary endpoint: a statistically significant improvement in clinimetric scores across the entire cohort.
• Disease activity was measured using:
  • Modified Bath Ankylosing Spondylitis Disease Activity Index (mBASDAI)
  • Ankylosing Spondylitis Disease Activity Score (ASDAS)
  • Swollen joint count (SJC)
  • Tender joint count (TJC)
  • Leeds Enthesitis Index (LEI)
  • Health Assessment Questionnaire (HAQ)
  • Patient Global Assessment (PGA)
  • Visual Analogue Scale (VAS) for Pain
  • Disease Activity Index for Psoriatic Arthritis (DAPSA)
• Clinimetric evaluations were performed at 6 months (t₆) and 12 months (t₁₂) to assess if patients showed a reduction in scores.
• Secondary endpoint: statistically significant improvements in MRI scores among patients with clinical signs of axial involvement.
• In patients with axial involvement, an MRI was conducted at baseline (t₀), 6 months (t₆), and after 12 months (t₁₂) of therapy to assess changes in MRI images following treatment with TREMFYA in patients with axial involvement.

Results

• A total of 99 patients with PsA were included in the study. Of these, 58 patients with PsA showed clinical signs of axial involvement.
• Among all 99 patients, selected baseline characteristics included:
  • 93.0% had peripheral joint pain
  • 7.0% reported isolated axial pain
  • 51.5% reported both peripheral and axial joint pain
  • 52.5 years old (average age)
  • 6.1% of patients were bio-naïve
• Results were evaluated at baseline (N=99), 6 months (n=87), and 12 months (n=64).
• Treatment success was characteristics by a statistically significant and consistent improvement in DAPSA, ASDAS, mBASDAI, and SPARCC MRI inflammation scores, indicating both clinical and imaging responses.
• The results for all clinimetric measures are summarized in Table: Clinimetric Evaluation Results
• The MRI evaluation results for SPARCC sacroiliac joint inflammation score (SIS) are summarized in Table: MRI Evaluation Results for SPARCC

Ruscitti et al (2024)² conducted a prospective, multicenter observational cohort study to evaluate the effectiveness of TREMFYA in adult patients with PsA and suggestive features of axial involvement.

Study Design/Methods

• Patients with PsA were assessed if previously treated with TREMFYA for at least 4 months in a real-world setting.
• All patients fulfilled the CASPAR criteria and in addition had to have clinical aspects of axial involvement (defined based on presence of suggestive features on x-ray and/or MRI). 
• The primary evaluation of axial-symptom reduction was evaluated by the change from baseline in Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) scores at the 4-month follow up visit.
• Other selected efficacy assessments at the 4-month follow-up also included ASDAS, DAPSA, as well as achieving the result of BASDAI ≤4.
• MRI findings on SI joints were assessed before and after treatment with TREMFYA.

Results

• A total of 67 patients with PsA and suggestive features of axial involvement in x-rays (89.5%) and/or MRIs (85.1%) were treated with TREMFYA.
  • 53 patients were treated with TREMFYA 100 mg every 4 weeks (q4w).
  • 14 patients were treated with TREMFYA 100 mg q8w.
• Selected baseline characteristics included:
  • Average age of 53.4 years old
  • Median disease duration of 8.0 years
  • 52.2% of patients had previous therapy with biologic disease modifying antirheumatic drugs (bDMARDs)
• At 4 months, patients receiving TREMFYA exhibited a significant reduction of BASDAI.
• The results for the reduction in BASDAI, ASDAS, and DAPSA are seen in Figure: Reduction in BASDAI, ASDAS, and DAPSA Scores at 4 Months

• Additionally, it was reported that 52.2% of patients in the cohort achieved BASDAI ≤4.
• Of the 67 patients in the cohort, 27 underwent MRI assessment of the sacroiliac joints.
  • A reduction of ≥0.80 in the sacroiliac joint lesion score was demonstrated in 70.3% of exams.
• The Authors noted that a total of 17.9% of patients reported minor adverse events, with injection site reactions as most common.

Retrospective Study

Almodovar et al (2025)³ conducted a retrospective multicenter observational study to assess the risk factors associated with response to TREMFYA or risankizumab in adult patients with axial and/or mixed PsA in a real-world clinical setting.

Study Design/Methods

• The study enrolled patients with axial and/or mixed PsA who were treated with TREMFYA and risankizumab across 24 hospitals in Spain.
• Axial PsA was determined by the investigator’s discretion.  
• Efficacy assessments included Axial Spondyloarthritis Disease Activity Score-C-reactive protein (ASDAS-CRP) and BASDAI scores at baseline and after 1, 3, 6, and 12 months.
• Responses were evaluated by achievement of clinically important improvement (CII) (ASDAS>1.1) or meeting BASDAI50 criteria.
• Adjustments were made for age, sex, and body mass index using multivariate predictive analysis and mixed models.

Results

• A total of 102 patients were included in the study with 80 patients in the TREMFYA group. Among all 102 patients studied, 87% had mixed PsA and 13% had axial PsA.
• Of the total patient population, the average treatment initiation age was 50 years old, and the average duration of PsA was 5.3 years.
• Clinical response outcomes were reported for patients receiving TREMFYA in Table: ASDAS-CRP and BASDAI50 Responses in TREMFYA-Treated Patients

Literature Search

A literature search of MEDLINE^®, EMBASE^®, BIOSIS Previews^®, and DERWENT^® (and/or other resources, including internal/external databases) was conducted on 04 August 2026.