C H A P T E R 1 7
Immune modulators
267
Rituximab is antibodies specific to sites on activated
B lymphocytes.
Natalizumab is an antibody specific to surface
receptors on all leucocytes except neutrophils.
Omalizumab is an antibody to immunoglobulin E,
an important factor in allergic reactions. It has not had
a great deal of success because of related respiratory
adverse effects.
Palivizumab is specific to the antigenic site on res-
piratory syncytial virus (RSV); it inactivates that virus.
It is used to prevent RSV disease in high-risk children.
Ustekinumab are antibodies specific to interleukins.
Pharmacokinetics
With the exception of erlotinib (an oral agent), all of the
monoclonal antibodies have to be injected. They can be
given IV, IM or SC. Because antibodies are proteins, they
are rapidly broken down in the GI tract. They are pro-
cessed by the body like naturally occurring antibodies.
Contraindications and cautions
Monoclonal antibodies are contraindicated in the
presence of any known allergy to the drug or to murine
products and in the presence of fluid overload. They
should be used cautiously with fever (treat the fever
before beginning therapy) and in individuals who have
had previous administration of the monoclonal antibody
(
serious hypersensitivity reactions can occur with repeat
administration
). Because of the potential for adverse
effects, they should not be used during pregnancy or
breastfeeding unless the benefit clearly outweighs the
potential risk to the fetus or neonate.
Adverse effects
The most serious adverse effects associated with the
use of monoclonal antibodies are acute pulmonary
oedema (dyspnoea, chest pain, wheezing), which is asso-
ciated with severe fluid retention, and cytokine release
syndrome (flu-like symptoms that can progress to
third-spacing of fluids and shock). Other adverse effects
that can be anticipated include fever, chills, malaise,
myalgia, nausea, diarrhoea, vomiting and increased sus-
ceptibility to infection.
Erlotinib is reserved for individuals whose disease
has progressed after other therapies.
The manufacturer of natalizumab stopped market-
ing the drug weeks after its release because of reports
of CNS complications. It was returned to the market in
June 2006 with warnings about the potential for CNS
complications.
Clinically important drug–drug interactions
Use caution and arrange to reduce the dose if a
monoclonal antibody is combined with any other
immunosuppressant drug because severe immune sup-
pression with increased infections and neoplasms can
occur.
Prototype summary: Basiliximab
Indications:
Treatment of acute organ rejection
in individuals who have undergone renal
transplantation.
Actions:
Monoclonal antibody to the antigen of
human T cells; functions as an immunosuppressant
by enabling T cells.
Pharmacokinetics:
Route Onset
Peak
Duration
IV Minutes
2–7 days
7 days
T
1/2
:
47 to 100 hours; metabolised in the tissues.
Adverse effects:
Headache, insomnia, vomiting,
nausea, diarrhoea, general oedema, upper
respiratory tract infection, fever, chills, increased
susceptibility to infection.
Care considerations for
people receiving immune suppressants
Assessment: History and examination
■
■
Assess for contraindications and cautions: any
known allergies to any of these drugs or their
components
to prevent hypersensitivity reactions
;
current status related to pregnancy or breastfeeding
because of the potential risk to the fetus or baby
;
history of renal or hepatic impairment
that might
interfere with drug metabolism and excretion
; and
history of neoplasm,
which could be exacerbated
with the use of these drugs
.
■
■
Perform a physical assessment
to determine
baseline status before beginning therapy and for
any potential adverse effects
; inspect the skin
to
detect the presence of any lesions
; obtain weight
to
monitor for fluid retention
; monitor temperature
to monitor for potential infection
; monitor pulse
and blood pressure
to assess the cardiac effects of
these drugs
; assess level of orientation and reflexes
to monitor for any CNS changes associated with
drug use
.
■
■
Obtain a baseline ECG
to evaluate cardiac
function
.
■
■
Assess the person’s renal and liver function,
including renal and liver function tests,
to
determine the appropriateness of therapy and
determine the need for possible dose adjustment
and toxic drug effects
.
