Trial results for the Phase 3 study (NCT06039189) investigating guselkumab for low body surface area moderate plaque psoriasis were posted on ClinicalTrials.gov on 2025-04-14. The study demonstrated that 74.2% of participants treated with guselkumab achieved an Investigator's Global Assessment (IGA) score of cleared (0) or minimal (1) at Week 16, compared to 12.4% in the placebo group.
Background
The study, titled "Study of Guselkumab Versus Placebo for the Treatment of Low Body Surface Area Moderate Plaque Psoriasis," aimed to evaluate the efficacy of guselkumab compared to an inactive drug in participants with low body surface area moderate plaque psoriasis and special site involvement.
Trial design
The study (NCT06039189) was a Phase 3, randomized, placebo-controlled trial that enrolled 338 participants. The trial investigated guselkumab in individuals diagnosed with moderate plaque psoriasis. Participants were assigned to receive either guselkumab 100 mg or placebo, with one group receiving placebo followed by guselkumab 100 mg.
Key results
The trial results demonstrated significant differences between the guselkumab and placebo groups across multiple efficacy endpoints at Week 16.
- For the outcome "Percentage of Participants Who Achieved an Investigator's Global Assessment (IGA) Score of Cleared (0) or Minimal (1)": 74.2% of participants in the guselkumab 100 mg group achieved this, compared to 12.4% in the placebo followed by guselkumab 100 mg group. An adjusted treatment difference of 61.8 (95.0% CI: 53.4 to 70.1) was observed, with a p-value of 0.001.
- Regarding "Percent Change From Baseline in Body Surface Area (BSA)": The guselkumab 100 mg group showed a mean change of -80.5% (Standard Deviation: 27.78), while the placebo followed by guselkumab 100 mg group showed a mean change of -5.6% (Standard Deviation: 54.33). The Least Square (LS) Mean Difference was -74.48 (95.0% CI: -83.33 to -65.62), with a p-value of 0.001.
- For "Percent Change From Baseline in Psoriasis Area Severity Index (PASI) Total Score": The guselkumab 100 mg group achieved a mean change of -82.6% (Standard Deviation: 24.24), versus -13.6% (Standard Deviation: 50.78) for the placebo followed by guselkumab 100 mg group. The LS Mean Difference was -68.96 (95.0% CI: -77.06 to -60.87), with a p-value of 0.001.
- For "Percentage of Participants Who Achieved IGA Score of Cleared (0)": 40.4% in the guselkumab 100 mg group compared to 3.5% in the placebo followed by guselkumab 100 mg group. The adjusted treatment difference was 36.9 (95.0% CI: 29.6 to 44.1), with a p-value of 0.001.
- For "Percentage of Participants Who Achieved PASI 90 Response": 52.9% in the guselkumab 100 mg group versus 6.2% in the placebo followed by guselkumab 100 mg group. The adjusted treatment difference was 46.6 (95.0% CI: 38.8 to 54.5), with a p-value of 0.001.
- For "Percentage of Participants Who Achieved PASI 100 Response": 32.4% in the guselkumab 100 mg group compared to 2.7% in the placebo followed by guselkumab 100 mg group. The adjusted treatment difference was 29.7 (95.0% CI: 23.0 to 36.5), with a p-value of 0.001.
What this means
The results from this Phase 3 trial indicate that guselkumab demonstrated significant improvements in key efficacy measures for participants with low body surface area moderate plaque psoriasis compared to placebo. The substantial differences observed in IGA, BSA, and PASI scores suggest that guselkumab could be an effective treatment option for this specific patient population, particularly those with special site involvement.
Source
The information regarding these trial results was obtained from ClinicalTrials.gov, a public database of clinical studies. The results for study NCT06039189, titled "Study of Guselkumab Versus Placebo for the Treatment of Low Body Surface Area Moderate Plaque Psoriasis," were posted on 2025-04-14 on clinicaltrials.gov.