Guselkumab is a human monoclonal antibody directed against IL-23. It is available as a subQ injection by the brand name of Tremfya for the treatment of plaque psoriasis.

Guselkumab (Tremfya) Uses:

• Plaque psoriasis:

  • It is indicated for the treatment of adults with moderate to severe plaque psoriasis who are candidates for systemic therapy or phototherapy.

Secukinumab is another biological drug available for the treatment of Psoriasis.

Read: Biologics for Psoriasis

Guselkumab (Tremfya) Dose in Adults

Guselkumab (Tremfya) Dose in the treatment of Plaque psoriasis:

• 100 mg subcutaneously at weeks 0, 4, and then every 8 weeks thereafter.

Use in children:

The safety and efficacy of the drug in children have not been established.

Pregnancy Risk Category: N (Not assigned)

• It is a monoclonal IgG anti-mouse antibody that crosses the placental boundary.
• It is possible to be exposed to the fetus, particularly during the third trimester.

Guselkumab use during breastfeeding:

• It is unknown whether the drug can be excreted into breastmilk. 
• It is possible for IgG immunoglobulins to enter breastmilk, which could lead to drug exposure in infants.
• Manufacturers recommend weighing the risks to the infant from drug exposure and the benefits for the mother.

Tremfya Dose in Kidney disease:

• The manufacturer has not recommended any adjustments in the dose.
• It has not been studied in patients with kidney disease.

Tremfya Dose in Liver disease:

• The manufacturer has not recommended any adjustments in the dose.
• It has not been studied in patients with liver disease.

Common Side Effects of Guselkumab (Tremfya):

• Infection:

  • Infection

• Respiratory:

  • Upper respiratory tract infection

Less Common Side Effects of Guselkumab (Tremfya):

• Central nervous system:

  • Headache

• Dermatologic:

  • Tinea

• Gastrointestinal:

  • Diarrhea
  • Gastroenteritis

• Hepatic:

  • Increased liver enzymes

• Immunologic:

  • Antibody development

• Infection:

  • Herpes simplex infection

• Local:

  • Injection site reaction

• Neuromuscular & skeletal:

  • Arthralgia

Contraindications to Guselkumab (Tremfya):

Severe allergic reactions to guselkumab and any component of the formula.

Warnings and precautions

• Hypersensitivity reactions

  • It is possible to have serious allergic reactions and need hospitalization.
  • Hypersensitivity reactions should not be ignored. Treatment should immediately be stopped and the appropriate treatment started.

• Infections

  • Guselkumab increases the risk of infection. Common infections are gastroenteritis, upper respiratory tract infections, cutaneous fungal infections and herpes simplex.
  • Patients who have had a history of chronic, recurring infections should be aware that therapy can have side effects.
  • Patients with a severe active infection should not begin treatment until the infection has resolved.
  • Patients should be monitored for possible infections. If patients notice symptoms that are clinically significant, they should inform their doctor immediately.
  • Guselkumab therapy should not be stopped until the serious infection is under control.
  • During the COVID-19 epidemic, cases of patients with psoriasis who received IL-23 inhibitors were published. 
  • The mildest form of coronavirus infection was found in most patients who received the drug.

• Tuberculosis

  • Before starting treatment, all patients should be tested for active and latent tuberculosis.
  • Patients with active tuberculosis should not be given the treatment.
  • Anti-tuberculosis treatment should be given to patients with latent tuberculosis before guselkumab is initiated.
  • Anti-TB treatment may be offered to patients with active or latent TB who cannot be confirmed to have received a proper course of treatment.
  • All patients must be monitored regularly for signs and symptoms of tuberculosis during treatment.

Guselkumab: Drug Interaction

Monitoring parameters:

• Monitor the patients for infections especially reactivation of tuberculosis.
• All patients should be screened for tuberculosis before initiating the treatment and periodically thereafter.

How to administer Guselkumab (Tremfya)?

• It is administered subcutaneously in the anterior abdomen 3 - 5 cms away from the navel, front of the thighs, or back of the upper arms.
• The injection should not be administered in red, inflamed, tender, thick, hard, scaly skin, or areas affected by psoriatic plaques.

Mechanism of action of Guselkumab (Tremfya):

• It is a monoclonal human IgG1 antibody that reduces serum levels of IL17A and IL-17F.
• It reduces proinflammatory cytokines (chemokines) and inhibits their release.

Metabolism:

• It is converted to small peptides or aminoacids via the catabolic pathways.

Bioavailability

• SubQ administration results in approximately 49%

Half-life elimination:

• 15 to 18 days

Time to peak:

• 5.5 days

International Brands of Guselkumab:

• Tremfya

Guselkumab Brand Names in Pakistan:

No Brands Available in Pakistan.