Trade Names: Humira
Drug Class: Biologic DMARD, TNF antagonist
Preparations: 40 mg injection
Dose: For RA 40 mg subQ injection every 2 weeks. Some other indications have a loading dose.
Mechanism of Action: A human IgG1 antibody against TNF-alpha that blocks the effects of the cytokine
Contraindications: Hypersensitivity, untreated tuberculosis and other opportunistic infections, sepsis, active infection, chronic localized or recurrent infections, demyelinating disease, optic neuritis, moderate-to-severe heart failure
Precautions: Increased risk of serious infections including TB and fungal. Exclude latent or active TB with a skin test or TB blood test (interferon-gamma release assays or IGRA). Caution in debilitated or high risk of infection. Exclude active hepatitis B infection or carriage. Avoid live virus vaccines and BCG. Do not use with other biologics. May exacerbate pre-exisiting demyelinating disease and heart failure.
Monitoring: Monitor clinically for infection. Periodic CBC. After therapy started, additional TB testing may be indicated for individuals likely to have exposure to TB.
Pregnancy Risk: B
Common: Injection site reactions, positive antinuclear and double stranded DNA antibodies
Less common: Allergy, infection (bacterial, but particularly opportunistic infections such as tuberculosis, listeriosis, and histoplasmosis)
Rare: Lymphoma (including fatal hepatosplenic T-cell lymphoma), hepatitis, demyelinating CNS disorders, optic neuritis, seizures, pancytopenia, drug-induced lupus, reactivation of hepatitis B, new onset psoriasis
Drug Interactions: Concurrent use of high-dose steroids and other immunosuppressants may increase risk of infection.
Patient Instructions: Avoid live virus vaccines; avoid pregnancy; stop injections and call your doctor if an infection or fever develops that lasts more than a few days
Comments: TNF antagonists are among the most effective treatments for RA. Patients start to respond quickly, usually within 4–6 weeks but maximum response may take 4-6 months. In RA, combined therapy with an anti-TNF drug and MTX is more effective than either drug alone. TNF antagonists are being explored in a range of diseases such as sarcoidosis and inflammatory eye disease. Risk of tuberculosis may be lower with etanercept than other TNF antagonists; comparative risk of adverse effects among individual TNF antagonists is not clear and side effects likely a class effect. Patients may form antibodies to anti-TNF drugs that decrease their effect. Concurrent treatment with MTX may reduce the frequency of this.
Clinical Pharmacology: Half-life is 14 days. Biologic agents are not metabolized and thus have few drug interactions.
Adapted from: RheumaKnowledgy