• Guselkumab is a monoclonal interleukin-23 antibody approved by FDA in July 2017 for the treatment of plaque psoriasis.
• Plaque psoriasis also is known as psoriasis vulgaris is an autoimmune disease which is characterized by red patches with white scales on top seen usually on the back of the forearms, scalp, shins (front of the leg below the knee) and around the navel area.
Guselkumab is prescribed along with either systemic treatment or phototherapy (UV light) to treat patients with moderate-to-severe plaque psoriasis in adults who do not show improvement only with topical medicines.
It is an interleukin-23 blocker that prevents inflammation in psoriasis.
Guselkumab should not be used in patients with:
• Allergy to the drug
• Present history of active tuberculosis
• Weak immune system
• Presence of opportunistic infections
• The recommended adult dose is 100mg of guselkumab as a subcutaneous injection taken once every 4 weeks during the first two doses and continued once for every 8 weeks thereafter for further doses.
• When a dose is missed, it should be taken as soon as the patient remembers and the patient should continue with the next dose as per the dosing schedule.
Guselkumab comes as a clear liquid of subcutaneous injection (100mg/ml) in a pre-filled syringe intended for single use.
• The injection sites are front thighs, back of upper arms or lower abdomen but avoiding exactly 2 inches or 5 cm around the navel area.
• The injections should not be given into tender, red or bruised, hard, thick or scaly skin affected by psoriasis.
• Before injecting, the injection should be removed from the refrigerator and allowed to reach the room temperature for 30 minutes.
• The solution should be checked for intact seal, clarity or presence of visible matter before injecting.
• Guselkumab increases the rate of infection and patients should be instructed to report to the physician if any sign of infection occurs during the treatment period.
• In case of serious infection reported during the treatment of guselkumab, the infection has to be treated first. Guselkumab treatment has to be stopped until the infection subsides.
• Patients should be checked for the presence of any infection prior to the guselkumab therapy particularly for the presence of tuberculosis (TB).
• In case of confirmation of TB or latent tuberculosis, the infection has to be treated before starting the treatment with guselkumab.
• Patients should be monitored regularly for the sign and symptoms of tuberculosis infection during and after the treatment with guselkumab.
• Gastrointestinal: Gastroenteritis, diarrhea, stomach pain
• Central Nervous System: Headache
• Respiratory: Upper respiratory tract infections, cough, hoarseness or sore throat, shortness of breath
• Skin: Tinea infections, herpes simplex infections, rashes, hives, itching, swelling, injection site reactions such as redness and itching
• Others: Joint pain, muscle pain, weight loss, frequent urination, burning micturition (burning sensation while passing urine), fever, sweat or chills and elevated liver enzymes
To reduce the rate of skin redness or soreness, using different sites for each injection is advised.
The dose schedule must be followed strictly and injecting it so often or frequent administration should be avoided.
• Avoid using live vaccines during guselkumab treatment to avoid the development of infection with the vaccine.
• Dosage adjustments may be needed when guselkumab treatment is taken along with narrow therapeutic index drugs such as theophylline and phenytoin.
• Guselkumab injection should be stored in a refrigerator at 2°C to 8°C in its original carton.
• It should be protected from light and not to be frozen or shaken.