Muromonab-CD3 (OKT-3) by Kimberly Fischer, RN BSN

Muromonab-CD3 is a mouse antibody produced from fusion of mouse plasma cells with human B-cell myeloma cells, targeting human T-cell CD-3. This mouse IgG2a was first approved in 1986 by FDA to be used in organ transplant rejection. It coats or binds CD-3, T-cell surface proteins, subjecting OKT-3/CD-3 complex to opsonization by the reticuloendothelial system in the liver with the first dose. The first dose of OKT-3 cause massive activation and subsequent depletion of oT-helper cells within the first day. With subsequent doses, OKT-3 causes the removal of CD-3 from T-cell surface such that the cell no longer functions as an immuno-competent T-cell.

Half-life: 20 hours
How to give: the content of glass ampule is first drawn up through non-protein binding 0.22 micron filter and given over 1-2 minutes IV Push via at least 20 gauge PIV or Central line

Side effects: fever (73%), chills (57%), dyspnea (21%), tremor (10%), nausea (11%), vomiting (13%), diarrhea (20%), wheezing (11%), chest pain (14%), pulmonary edema, aseptic meningitis, seizures, e
ncephalopathy.
Cytokine Release Syndrome: Also known as, first dose response, occurs with first dose ± 2nd dose, but may be delayed up to a week. T-cells are massively activated when OKT-3 binds to the CD-3 complex of the CD-4 cells (T-helper cells). The release of cytokines, IL-2, IL-6, tumor necrosis factor-alpha, and interferon-gamma, into systemic circulation then stimulates the production of leukotrienes, prostaglandins, and endoperoxides.
Side effects: fever (73%), chills (57%), dyspnea (21%), tremor (10%), nausea (11%), vomiting (13%), diarrhea (20%), wheezing (11%), chest pain (14%), pulmonary edema, aseptic meningitis, seizures, encephalopathy primarily due to decreased cardiac contractility, coronary vasospasm, increased pulmonary capillary permeability, changes in bronchial muscle contractility and GI smooth muscle contractility. These cytokine release syndrome occurs within the first hour of the muromonab-CD1 administration and persists for several hours.

Vital Sign Monitoring:
• Place patient on 2 liters oxygen via nasal cannula to keep O2 saturation>90%
• Dose #1 and #2:
-Every 15minutes x 4, every 30minutes x 4, then every hour until the patient is stable
• Dose #3 and on:
-Every 30minutes x 2, then every hour until stable
Labs:
• BUN and creatinine
• Amylase
• WBC with differential
• Platelets
• CD-3 count on Day 4
• Chest X-ray prior to initiation of first dose to monitor fluid status of lungs; diuretics and/or dialysis must be used to bring patient’s weight to < 3% of their dry weight
Additional Informaton:
• Meperidine may be used to control rigors
• Patient may need to transferred to ICU if fluid overloaded.