Infliximab; Uses, Dosage, Side Effects, Drug Interactions

Infliximab works by binding to TNF-α. TNF-α is a chemical messenger (cytokine) and a key part of the autoimmune reaction. In rheumatoid arthritis?, infliximab seems to work by preventing TNF-α from binding to its receptor in the cell.

Mechanism of action of Infliximab

Infliximab is aIgG1κ monoclonal antibody that binds to soluble and transmembrane forms of TNF-α with high affinity to disrupt the pro-inflammatory cascade signaling. Binding of the antibody to TNF-α prevents TNF-α from interacting with its receptors. Infliximab does not neutralize TNF-α (lymphotoxin-α), a related cytokine that utilizes the same receptors as TNF-α . Blocked actions of TNF-α further leads to downregulation of local and systemic? pro-inflammatory cytokines (i.e. IL-1, IL-6), reduction of lymphocyte? and leukocyte? migration to sites of inflammation, induction of apoptosis of TNF-producing cells (i.e. activated monocytes and T lymphocytes), increased levels of nuclear factor-κB inhibitor, and reduction of reduction of endothelial adhesion molecules and acute? phase proteins . Its inhibitory actions on TNF-α was demonstrated in human fibroblasts, endothelial cells, neutrophils, B and Tlymphocytes and epithelial cells. Infliximab also atteunates the production of tissue degrading enzymes synthesized by synoviocytes and/or chondrocytes. According to a transgenic mice study that developed polyarthritis due to constitutive levels of human TNF-α, infliximab decreased synovitis and joint erosions in collagen-induced arthritis and allows eroded joints to heal.

Indications of Infliximab

• Ankylosing spondylitis 
• Crohn’s Disease
• Plaque Psoriasis
• Psoriatic Arthritis
• Rheumatoid Arthritis
• Ulcerative Colitis 
• Giant Cell Arteritis
• Inflammatory Bowel Disease
• Juvenile Idiopathic Arthritis
• Neurosarcoidosis
• Plaque Psoriasis
• Polychondritis
• Psoriasis
• Pulmonary Fibrosis
• Sjogren’s Syndrome?
• Spondyloarthritis
• Subcorneal pustular dermatosis
• Toxic epidermal necrolysis
• Ulcerative colitis

Contra-Indications of Infliximab

• Tuberculosis
• Infection? caused by Blastomyces dermatitidis Fungus
• Opportunistic fungal infection
• Pneumonia 
• Severe infection
• Infection that Lasts a Long Time
• Malignant? melanoma?
• Leukemia
• Diabetes that is not under control
• Reduction in the body’s resistance to infection
• Acquired decrease of all cells in the blood
• Low blood counts due to bone marrow failure
• Decreased neutrophils a type of white blood cell
• Multiple sclerosis
• Demyelinating Disease
• Sudden blindness and pain Upon moving the eye
• Heart failure
• Pneumonia caused by legionella pneumophila bacteria
• Hardening of the liver? caused by alcohol
• Liver inflammation caused by body’s own immune response
• Seizures
• Reactivated tuberculosis
• Sepsis? syndrome
• Malignant lymphoma?
• Relapse? of hepatitis? B infection symptoms
• Hepatitis B
• Hepatosplenic T-cell lymphoma
• Opportunistic viral infection

Dosage of Infliximab

Strengths: abda 100 mg; dyyb 100 mg; 100 mg

Rheumatoid Arthritis

• 3 mg/kg given as an IV induction regimen at 0, 2, and 6 weeks followed by a maintenance regimen of 3 mg/kg IV every 8 weeks thereafter;
• Adjusting the dose up to 10 mg/kg IV or treating as often as every 4 weeks may be considered for patients who have an incomplete response

Ankylosing Spondylitis

• 5 mg/kg given as an IV induction regimen at 0, 2, and 6 weeks followed by a maintenance regimen of 5 mg/kg IV every 6 weeks thereafter

Psoriatic Arthritis

• 5 mg/kg given as an IV induction regimen at 0, 2, and 6 weeks followed by a maintenance regimen of 5 mg/kg every 8 weeks thereafter

Psoriasis

• 5 mg/kg given as an IV induction regimen at 0, 2, and 6 weeks followed by a maintenance regimen of 5 mg/kg IV every 8 weeks thereafter

Crohn’s Disease 

• 5 mg/kg given as an IV induction regimen at 0, 2, and 6 weeks followed by a maintenance regimen of 5 mg/kg IV every 8 weeks thereafter; treatment with 10 mg/kg IV may be considered for patients who respond and then lose their response

Side Effects of Infliximab

The most common

• Nausea and vomiting
• Back pain
• Bladder pain
• multiple sclerosis,
• Severe diarrhea
• Vaginal thrush
• Skin rash redness or itching, pain, or swelling at the injection site
• a Headache
• chest pain
• constipation
• a cough
• diarrhea or loose stools
• difficulty with breathing
• dizziness
• heartburn
• muscle pain

More common

• Abdominal or stomach pain, discomfort, or tenderness
• chills or fever
• Heartburn
• Indigestion
• a headache, severe and throbbing
• joint or back pain
• Loss of energy or weakness
• pain or burning in the throat
• runny or stuffy nose
• muscle aching or cramping
• muscle pains or stiffness
• chest pressure or squeezing pain in the chest
• discomfort in arms, shoulders, neck or upper back
• excessive sweating
• feeling of heaviness, pain, warmth and/or swelling in a leg or in the pelvis
• sudden tingling or coldness in an arm or leg
• sudden slow or difficult speech
• sudden drowsiness or need to sleep
• fast breathing
• sharp pain when taking a deep breath
• fast or slow heartbeat
• coughing up blood
• rust colored urine
• decreased amount of urine

Rare

• Anxiety
• change in vision
• seizures
• abnormal or fast heart rate
• tremors
• weight loss
• chest pain or tightness
• confusion
• a cough
• Agitation
• arm, back, or jaw pain
• blurred vision
• chest pain or discomfort
• convulsions
• extra heartbeats
• fainting
• hallucinations
• a headache
• irritability
• lightheadedness
• mood or mental changes
• muscle pain or cramps
• muscle spasm or jerking of all extremities

Drug Interactions of Infliximab

Infliximab may interact with the following drugs, supplements, & may change the efficacy of the drug

• adalimumab
• bacillus Calmette-Guérin (BCG)
• belimumab
• canakinumab
• certolizumab pegol
• live vaccines (e.g., measles, mumps, and rubella (MMR), tuberculosis (BCG), yellow fever)
• cyclophosphamide
• denosumab
• fingolimod
• leflunomide
• nivolumab
• natalizumab
• pimecrolimus
• roflumilast
• sulfasalazine
• tacrolimus
• tocilizumab
• tofacitinib
• trastuzumab
• vaccines (e.g., yellow fever, BCG, cholera, typhoid, varicella, meningococcal, diphtheria)

Pregnancy Catagory

FDA Pregnancy Category B

Pregnancy

This medication is not recommended for use during pregnancy. Women who may become pregnant should use an effective method of birth control while they are taking this medication and for at least 6 months after the last treatment.

Lactation

It is not known if infliximab passes into breast milk. Women should not breastfeed while they are taking this medication and should not start breastfeeding until at least 6 months after the last treatment. The safety and effectiveness of this medication have not been established for children under 6 years old. It can be used to treat children 6 years and older who have moderate-to-severe ulcerative colitis. It can also be used to treat children 9 years and older who have moderate-to-severe Crohn’s disease.

References