Real-Life Evaluation of Guselkumab Dosing Interval Adjustments

February 18, 2026 updated by: Centre Hospitalier Universitaire de Nice

Real-Life Evaluation of Guselkumab Dosing Interval Adjustments. SPAcing-GUS

"Guselkumab (Tremfya®) is a fully human monoclonal antibody that selectively targets interleukin-23 (IL-23), a key cytokine involved in the inflammatory pathways of psoriasis. This biologic therapy received marketing authorization in France in 2018 for the treatment of moderate-to-severe plaque psoriasis in adults requiring systemic therapy. This indication includes patients with extensive disease, with or without significant psychosocial impact, and those who have had an inadequate response, contraindication, or intolerance to at least two conventional systemic non-biologic treatments (such as methotrexate, ciclosporin, or acitretin) or phototherapy. The GUIDE study demonstrated that guselkumab injection intervals may be extended in psoriasis "super-responders" (defined as PASI 0 at Weeks 20 and 28). In this study, dosing intervals were extended from 8 to 16 weeks starting at Week 28 without waiting for prolonged confirmation of complete response. While the primary endpoint (maintenance of PASI <3 at Week 64) showed non-inferiority between the q8 and q16 groups, patients receiving injections every 16 weeks experienced a significantly greater loss of PASI 0 and PASI 1 responses at Week 64. This was associated with a reduction in quality of life (measured by DLQI) in the 16-week group compared with the 8-week group. Nevertheless, GUIDE highlights the flexibility of guselkumab administration, particularly in super-responders at Week 28.

Guselkumab (Tremfya®) is a biologic treatment used for moderate to severe psoriasis. It works by blocking a molecule involved in inflammation and has been approved in France since 2018. The standard dosing schedule is one injection every 8 weeks after the initial treatment phase.

A clinical study (GUIDE) showed that in some patients who respond extremely well to treatment ("super responders"), it may be possible to space the injections further apart. However, extending injections to every 16 weeks slightly reduced the chance of maintaining complete skin clearance in some patients. In real-life practice, many dermatology centers gradually increase the time between injections once patients achieve stable and almost complete clearance of their psoriasis. The approach varies between centers.

Using large French healthcare databases, we studied how guselkumab is used in routine practice. We found that about 38% of patients spaced their injections beyond the recommended 8 weeks, and this proportion increased to 47% in patients treated for more than 2 years. Importantly, spacing injections did not reduce how long patients stayed on treatment. Among patients who stopped guselkumab after spacing their doses, most did not need another systemic treatment for at least one year, suggesting that some patients may benefit from temporary "treatment breaks." These results suggest that for certain patients with well-controlled psoriasis, guselkumab dosing may be safely adjusted, offering greater flexibility, reduced treatment burden, and potentially lower healthcare costs."

Study Overview

Status

Recruiting

Conditions

Intervention / Treatment

Study Type

Observational

Enrollment (Estimated)

100

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact Backup

Study Locations

  • France
    • Alpes Maritimes
      • Nice, Alpes Maritimes, France, 06000

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

N/A

Sampling Method

Probability Sample

Study Population

Eligible patients diagnosed with cutaneous psoriasis treated with guselkumab, for whom a dosing interval extension was proposed

Description

Inclusion Criteria:

  • .Adult patients receiving guselkumab for cutaneous psoriasis. 2.
  • Guselkumab treatment with dosing intervals exceeding 9 weeks.

Exclusion Criteria:

  • Patients receiving guselkumab primarily for joint involvement.
  • Patients for whom guselkumab dosing was extended due to surgery, pregnancy, or infection.
  • Patients for whom the PASI or IGA score was not assessed during visits

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

Cohorts and Interventions

Group / Cohort
Intervention / Treatment
Patients diagnosed with cutaneous psoriasis
Treated with guselkumab for whom dose spacing has been proposed.
Drug: Guselkumab (Tremfya®)

Guselkumab (Tremfya®) is a fully human monoclonal antibody that selectively targets the p19 subunit of interleukin-23 (IL-23), a key cytokine involved in the inflammatory pathway of psoriasis. By inhibiting IL-23, guselkumab reduces downstream inflammatory signaling and improves psoriatic skin lesions. The aprouved dosing regimen:

  • 100 mg administered by subcutaneous injection at Week 0 and Week 4 (induction phase),
  • followed by 100 mg every 8 weeks thereafter (maintenance phase).

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Evaluation of the modalities of guselkumab dose spacing
Time Frame: At the inclusion
PASI Score ( Psoriasis Area and Severity Index )
At the inclusion
Psoriasis severity
Time Frame: At the inclusion
PASI Score ( Psoriasis Area and Severity Index )
At the inclusion
Duration of guselkumab treatment prior to dose spacing
Time Frame: At the inclusion
In weeks
At the inclusion

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Evaluation of patient characteristics in individuals undergoing Dose spacing
Time Frame: At the inclusion
PASI Score Psoriasis Area and Severity or IGA score Investigator Global Assessment graded on a scale from 0 to 4
At the inclusion
Evaluation of Guselkumab Treatment Persistence During Dose Spacing
Time Frame: At the inclusion
PASI Score Psoriasis Area and Severity or IGA score score Investigator Global Assessment graded on a scale from 0 to 4
At the inclusion

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Centre Hospitalier Universitaire de Nice

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

October 16, 2025

Primary Completion (Estimated)

April 16, 2026

Study Completion (Estimated)

April 16, 2026

Study Registration Dates

First Submitted

February 18, 2026

First Submitted That Met QC Criteria

February 18, 2026

First Posted (Actual)

February 24, 2026

Study Record Updates

Last Update Posted (Actual)

February 24, 2026

Last Update Submitted That Met QC Criteria

February 18, 2026

Last Verified

February 1, 2026

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 26Dermato01

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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