The US FDA has approved dupilumab as the first and only treatment for prurigo nodularis, a chronic inflammatory skin disorder characterized by multiple, severely itchy nodules particularly on the arms and legs and greatly diminishing the quality of life of the patient. Dupilumab, a fully human monoclonal antibody, which is an interleukin-4 receptor alpha antagonist. It has been approved as an injectable formulation to be administered subcutaneously for adult patients.

Dupilumab is already approved for atopic dermatitis, asthma, chronic rhinosinusitis with nasal polyposis and eosinophilic esophagitis.

Formulation: Single-dose pre-filled pen or single dose pre-filled syringe with needle shield

Dosage and administration: 600 mg initial dose (two 300 mg injections) subcutaneously, followed by 300 mg every alternate week

Side effects: Injection site reactions, herpes simplex virus infections, common cold, muscle pain, diarrhea, throat pain.

Contraindication: Known hypersensitivity to dupilumab or any excipients

Warning and precautions

• Dupilumab may cause new onset or worsen existing eye problems (such as conjunctivitis, keratitis) or arthralgia. Hence, referral for ophthalmological/ rheumatological examination may be required.
• Vasculitis rash, worsening of pulmonary symptoms or neuropathy may occur.
• Avoid abrupt discontinuation of steroids when starting treatment with dupilumab.
• Avoid live vaccines.
• Before starting dupilumab, pre-existing helminth infections must be treated.

Sources

1. US FDA, Dupixent prescribing information. https://www.accessdata.fda.gov/drugsatfda_docs/label/2022/761055s044lbl.pdf
2. https://www.medpagetoday.com/dermatology/generaldermatology/100967, dated Sept. 30, 2022.