The Phase 3 study for guselkumab (Tremfya) in participants with active psoriatic arthritis reached primary completion on 2024-10-28, with key results posted on ClinicalTrials.gov. The trial demonstrated that guselkumab 100 mg q8w achieved an ACR20 response rate of 63.0% at Week 24, compared to 35.9% for the placebo group.
Background
This study evaluated guselkumab in participants with active psoriatic arthritis (PsA) who had an inadequate response or intolerance to one prior anti-tumor necrosis factor (TNF) alpha agent. The trial aimed to assess the reduction in signs and symptoms of PsA in this patient population.
Trial design
The Phase 3 study (NCT04936308) enrolled 453 participants with active psoriatic arthritis. The trial's purpose was to evaluate the efficacy of guselkumab treatment in participants with active PsA who had an inadequate response and/or intolerance to a prior anti-TNF alpha agent. The study compared two dosing regimens of guselkumab 100 mg (every 8 weeks and every 4 weeks) against a placebo arm. A key outcome measured was the percentage of participants achieving an American College of Rheumatology (ACR) 20 response at Week 24.
Key results
The trial reported the following key measurements at Week 24:
- Percentage of Participants Who Achieved an American College of Rheumatology (ACR) 20 Response:
- Guselkumab 100 mg q8w: 63.0%
- Guselkumab 100 mg q4w: 60.9%
- Placebo Followed by Guselkumab 100 mg: 35.9%
- Percentage of Participants Who Achieved a Psoriasis Response of Investigator's Global Assessment (IGA) Psoriasis Score of 0 or 1 and >=2 Grade Reduction From Baseline (among participants with >=3% Body Surface Area (BSA) involvement):
- Guselkumab 100 mg q8w: 60.7%
- Guselkumab 100 mg q4w: 56.8%
- Placebo Followed by Guselkumab 100 mg: 18.8%
- Percentage of Participants Who Achieved Psoriasis Area and Severity Index (PASI) 90 Response (among participants with >=3% BSA Psoriatic Involvement and an IGA Score of >=2 (Mild) at Baseline):
- Guselkumab 100 mg q8w: 47.6%
- Guselkumab 100 mg q4w: 54.9%
- Placebo Followed by Guselkumab 100 mg: 12.5%
- Change From Baseline in Health Assessment Questionnaire Disability Index (HAQ-DI) Score:
- Guselkumab 100 mg q8w: -0.3955 units on a scale
- Guselkumab 100 mg q4w: -0.4159 units on a scale
- Placebo Followed by Guselkumab 100 mg: -0.2359 units on a scale
What this means
The results from this Phase 3 trial indicate that guselkumab significantly improved outcomes for participants with active psoriatic arthritis who had an inadequate response or intolerance to prior anti-TNF alpha therapy. Both the 100 mg q8w and 100 mg q4w dosing regimens demonstrated superior ACR20 response rates compared to placebo. Specifically, the 63.0% ACR20 response for guselkumab 100 mg q8w and 60.9% for guselkumab 100 mg q4w represent a substantial improvement over the 35.9% seen in the placebo group. Additionally, guselkumab showed notable improvements in psoriasis-specific endpoints, including IGA Psoriasis Score and PASI 90 response, as well as functional improvements indicated by the HAQ-DI score. These findings suggest that guselkumab could offer an effective treatment option for this challenging-to-treat psoriatic arthritis population.
Source
The information regarding the primary completion and key results of this trial was obtained from ClinicalTrials.gov, a public database of clinical studies. The results for the study NCT04936308, titled "Guselkumab in Active Psoriatic Arthritis Participants With Inadequate Response/Intolerance to One Prior Anti-TNF Alpha Agent", were posted on 2024-10-28 on clinicaltrials.gov.