By Candy Finley, RN, IgCN.

Infliximab is an intravenously administered genetically engineered monoclonal antibody that neutralizes inflammation caused by a protein called tumor necrosis factor alpha (TNFα) by binding to the soluble and transmembrane forms of TNFα with its receptors. Elevated concentrations of TNFα have been found in the tissues and fluids of patients with the Food and Drug Administration (FDA)-approved diagnoses. Infliximab controls the activity of several inflammatory chemicals. It is FDA-approved to treat rheumatoid arthritis, ankylosing spondylitis, Crohn's disease, plaque psoriasis, psoriatic arthritis and ulcerative colitis. Once established on treatment, symptoms should start to improve over a period of two to twelve weeks.

Patients treated with infliximab are at increased risk for developing serious infections that may lead to hospitalization or death. Serious infections include tuberculosis, invasive fungal infections and bacterial or viral infections caused by opportunistic pathogens. For this reason, infliximab should not be administered in patients with an active infection, including clinically important localized infections. Patients at higher risk of infection include those who are greater than 65 years-old, have co-morbid conditions and/or those taking concomitant immunosupressants.

Infliximab requires close clinical monitoring as it has been known to contribute to other serious problems, including increased risk of malignancy, hepatitis B virus reactivation and heart failure. Serum sickness-like reactions are delayed hypersensitivity reactions and have been observed 3 - 12 days after infliximab therapy, and when infliximab therapy has been reinstituted following an extended period off infliximab. Associated symptoms include fever, rash, headache, sore throat, myalgias, arthralgias, hand or facial edema and/or dysphagia.

The most common infliximab side effects, occurring in >10% of patients, are infections (such as upper respiratory, sinusitis and pharyngitis), infusion-related reactions (IRR), headache and abdominal pain. Approximately 20% of infliximab-treated patients experienced an IRR compared to 10% of placebo-treated patients. IRR occur during or within 2 hours after the infusion and include flu-like symptoms, headache, dyspnea, hypotension, fever, chills, gastrointestinal symptoms and skin rash. Pre-medications may be administered at the discretion of the prescriber and could include acetaminophen, anti-H1 histamines (e.g., diphenhydramine, loratadine) and/or anti-H2 histamines (e.g., famotidine) and/or corticosteroids. Mild to moderate IRR may improve following slowing or suspension of the infusion and upon resolution, re-initiation at a slower infusion rate and/or administration of acetaminophen, anti-histamines and/or corticosteroids. If the patient does not tolerate the infusion after these interventions, discontinue infliximab and contact NuFACTOR.

Anaphylaxis may occur at any time during an infliximab infusion. Hypersensitivity reactions, including urticaria, dyspnea, and/or hypotension may occur during or within 2 hours of an infusion. NuFACTOR obtains prescriber orders for treatment of anaphylaxis. The nurse should ensure the kit is readily available for all doses.

Prior to administering each dose, screen for active infections, infusion-related reactions to past doses and any other adverse reactions. It is not recommended to administer infliximab in the presence of infection. If an infection is present, inform NuFACTOR and do not administer infliximab until cleared by the prescriber. If prescribed, ensure the patient has taken oral pre-medications at least 30 minutes prior to the infusion or as ordered.

Assess baseline vital signs (blood pressure, pulse and temperature) prior to the start of the infusion. After obtaining IV access, prepare the infliximab. Infliximab is available as a 100 mg vial of lyophilized powder. Each vial should be reconstituted by directing the stream of 10 ml of sterile water for injection down the wall of the vial. Avoid shaking and prolonged or vigorous agitation. Foaming is not unusual and should dissipate after allowing the vial to stand for 5 minutes. The reconstituted solution should be colorless to light yellow and opalescent. Do not use if the powder is not fully dissolved or if opaque particles, discoloration or other foreign bodies are present. Dilute the infliximab in sodium chloride 0.9% (normal saline or NS) 250 ml. A volume of NS equivalent to the volume of reconstituted infliximab may need to be removed from the NS container to yield a final infliximab concentration of 0.4 - 4 mg/ml. The pharmacist will determine if this is necessary. Infliximab vials are non-preserved and infusions should begin within three hours of preparation.

Infliximab should be administered using a peristaltic pump or the NuFACTOR standard method, gravity rate controlled device (e.g., Dial-a-Flow). The infusion set should include an in-line, non-pyrogenic, low-protein-binding filter (pore size of 1.2μ or less). Infliximab should be administered intravenously over a period of not less than two hours. A suggested infusion schedule is: 25 ml/hr x 10 minutes. If tolerated at each step, rates are increased to 50 ml/hr x 10 minutes, 75 ml/hr x 10 minutes and then 125 ml/hr for the remainder of infusion. If using a gravity rate controlled device, the nurse must count the drops/minute at each titration rate increase. Assess vital signs minimally before a rate change and every 30 minutes in patients who have not experienced an infusion related reaction or minimally every 15 minutes in patients who have had a past history of an infusion related reaction and at the end of the infusion.

If the patient experiences significant changes in vital signs, slow or stop the infusion. If the infusion is stopped and symptoms resolve, re-initiate at a slower rate and slowly titrate as tolerated. Inform the NuFACTOR pharmacist.

If the patient experiences mild to moderate infusion related reactions such as flu-like symptoms, headache, dyspnea, hypotension, fever, chills, gastrointestinal symptoms and skin rash, slow or stop the infusion. If ordered, administer anti-histamine, acetaminophen or corticosteroid. If the infusion is stopped and the symptoms resolve, re-initiate at a slower rate and slowly titrate as tolerated. Inform the NuFACTOR pharmacist.

If the patient experiences severe hypersensitivity such as urticaria, dyspnea, and/or hypotension or anaphylaxis symptoms, stop the infusion. Follow anaphylaxis orders and inform the prescriber immediately. Inform the NuFACTOR pharmacist when able.

FDA-approved Dosing Guidelines:

Sources:

• REMICADE^® package insert dated October 2015
• Lexicomp Online (online.lexi.com)