What type of drug is Tremfaya (guselkumab)?

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Tremfya (Guselkumab) Drug Classification

Tremfya (guselkumab) is a fully human IgG1 lambda monoclonal antibody that selectively inhibits interleukin-23 (IL-23) by binding to its p19 subunit, making it an IL-23 inhibitor biologic agent. 1, 2

Mechanism of Action

  • Guselkumab is a human immunoglobulin G1 lambda (IgG1λ) monoclonal antibody with an approximate molecular weight of 147 kDa, produced in mammalian cell lines using recombinant DNA technology 2
  • It works by blocking the p19 subunit of IL-23, disrupting the type 17 helper T cell/IL-17 pathway 3
  • This selective inhibition of IL-23 distinguishes it from ustekinumab (which blocks both IL-12 and IL-23), allowing IL-12-dependent cascades to remain functional 4

FDA-Approved Indications

Tremfya is approved for treating adults with: 1, 2

  • Moderate-to-severe plaque psoriasis who are candidates for systemic therapy or phototherapy (FDA approval July 13,2017) 1
  • Active psoriatic arthritis (FDA approval 2020) 5
  • Moderately to severely active ulcerative colitis 2
  • Moderately to severely active Crohn's disease 2

Drug Class Positioning

  • Guselkumab is the first selective IL-23 inhibitor approved for psoriatic arthritis, representing a novel mechanism of action distinct from TNF-α inhibitors, IL-17 inhibitors, and the non-selective IL-12/23 inhibitor ustekinumab 5, 4
  • It belongs to the broader category of biologic disease-modifying agents used in immune-mediated inflammatory diseases 1

Available Formulations

The drug is available as: 2

  • Subcutaneous injection: 100 mg/mL solution in prefilled syringes, prefilled pens (TREMFYA PEN), or One-Press patient-controlled injectors
  • Intravenous infusion: 10 mg/mL solution in 20 mL single-dose vials (used for induction dosing in ulcerative colitis and Crohn's disease) 2

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

Guselkumab for the Treatment of Psoriasis.

BioDrugs : clinical immunotherapeutics, biopharmaceuticals and gene therapy, 2018

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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