Infliximab
A chimeric anti-TNF-alpha antibody given by intravenous infusion for inflammatory bowel disease, rheumatoid arthritis and psoriasis.
Drug card
- Class
- TNF inhibitor
- How it works
- Binding TNF-alpha so it cannot activate its inflammatory receptors
- Used for
- Crohn's disease, including fistulizing disease
- Ulcerative colitis
- Rheumatoid arthritis, with methotrexate
- Ankylosing spondylitis
- Known for
- Serious infections, including invasive fungal ones
- Reactivation of latent tuberculosis
- Infusion reactions (fever, chills, breathlessness, rash)
- Its name
- -mab means a monoclonal antibody; -ximab means a chimeric monoclonal antibody
Study it as a flashcard, and it comes back before you forget it.
Mechanism of action
How does infliximab work?
Infliximab is a chimeric mouse-human IgG1 antibody that binds both soluble and transmembrane TNF-alpha with high affinity, neutralizing it so it cannot reach its receptors; it does not neutralize lymphotoxin-alpha. Cells that carry membrane TNF-alpha and are bound by it can be lysed.
Like other TNF inhibitors: TNF-alpha is a cytokine that drives inflammation and tissue damage in rheumatoid arthritis, inflammatory bowel disease and psoriasis, partly by inducing IL-1, IL-6 and adhesion molecules that recruit leukocytes. These biologics bind soluble and membrane-bound TNF-alpha and stop it engaging its p55 and p75 receptors. Infliximab and adalimumab are monoclonal antibodies; etanercept is a soluble receptor fusion protein.
Uses
What is infliximab used for?
- Crohn's disease, including fistulizing disease
- Ulcerative colitis
- Rheumatoid arthritis, with methotrexate
- Ankylosing spondylitis
- Plaque psoriasis and psoriatic arthritis
Side effects
Side effects of infliximab
- Serious infections, including invasive fungal onesKnown forSerious
- Reactivation of latent tuberculosisKnown forSerious
- Infusion reactions (fever, chills, breathlessness, rash)Known forSerious
- Delayed serum sickness-like reactionSerious
- Hepatitis B reactivationSerious
- Severe liver injurySerious
- Lymphoma, including hepatosplenic T-cell lymphomaSerious
- New or worse heart failureSerious
- Heart attack or stroke around the infusionSerious
- Demyelinating disease (multiple sclerosis, optic neuritis)Serious
- Lupus-like syndrome
- Low blood counts, including pancytopeniaSerious
Known for marks what an exam expects you to know it for.
Watch for
Cautions and what sets it apart
- Latent tuberculosis is tested for and treated before the first infusion, and hepatitis B is screened for.
- Contraindicated at higher doses in moderate or severe heart failure.
- Hepatosplenic T-cell lymphoma is most likely in young men with IBD who also take azathioprine or mercaptopurine.
- Live vaccines are avoided during treatment and in babies exposed in the womb for their first 6 months.
Good to know: Its variable region comes from a mouse, so a past severe reaction to murine proteins rules it out; antibodies against the drug can form and cause reactions or loss of effect.
Remember it
A way to remember it
Check the two Bs before blocking TNF: TB and hepatitis B
TNF inhibitors can reactivate latent tuberculosis and hepatitis B, so both are screened for before the first dose and watched for during treatment.
Written for biofideX
Its name
-mab means monoclonal antibody
Older names show the source: -ximab chimeric, -zumab humanized, -umab human. WHO stopped adding that part in 2017 and dropped -mab in 2021; new names end in -tug, -bart, -ment or -mig.
-ximab means chimeric monoclonal antibody
Chimeric antibodies join mouse variable regions to human constant regions, as in rituximab (against CD20) and infliximab (against TNF). WHO stopped adding this part to names in 2017.
- Every drug name stem
Its class
TNF inhibitors
Other TNF inhibitors with a card:
Easily mixed up with CD20-targeted antibodies and aminosalicylates.
Sources
Checked against
Written for biofideX in plain words, after checking these references:
For learning pharmacology, not for treatment decisions: no doses are given, and a prescriber, pharmacist or the product's own label is the word on any one patient. Spotted a mistake? Tell us and we'll correct it.
Targeted therapy and the immune system
Infliximab is one of 13 drugs practiced together here: their classes, how they work, what they treat and what they're known for.
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