SIDE EFFECTS
The following serious adverse reactions occur with Elspar
treatment [see WARNINGS AND PRECAUTIONS]:
- Anaphylaxis and serious allergic reactions
- Serious thrombosis
- Pancreatitis
- Glucose intolerance
- Coagulopathy
- Hepatotoxicity and abnormal liver function
- Posterior Reversible Encephalopathy Syndrome (PRES)
- Risk of Medication Errors
The most common adverse reactions with Elspar are
allergic reactions (including anaphylaxis), hyperglycemia, pancreatitis,
central nervous system (CNS) thrombosis, coagulopathy, hyperbilirubinemia, and
elevated transaminases.
Clinical Trials and Post-Marketing Experience
The adverse reactions included in this section were
identified in single-arm clinical trials in which Elspar was administered as
part of a multi-agent regimen or from spontaneous post-marketing reports or
published literature.
Because these adverse events were identified in clinical
trials that were not designed to isolate the adverse effects of Elspar or were
reported voluntarily from a population of uncertain size, it is not always
possible to reliably estimate their frequency or establish a causal
relationship to drug exposure.
Serious Adverse Reactions
Anaphylaxis and serious allergic reactions. Allergic
reactions have occurred with the first dose and with subsequent doses of
Elspar. The risk of serious allergic reactions appears to be higher in patients
with prior exposure to Elspar or other Escherichia coli-derived
L-asparaginases.
Serious thrombosis, including sagittal sinus thrombosis
Pancreatitis, in some cases fulminant or fatal
Glucose intolerance, in some cases irreversible
Coagulopathy, including increased prothrombin time,
increased partial thromboplastin time, and decreased fibrinogen, protein C,
protein S and antithrombin III. CNS hemorrhages have been reported.
Hepatotoxicity, in some cases fatal, can occur.
Central Nervous System effects including coma, seizures,
and hallucinations.
Common Adverse Reactions
Azotemia, liver function abnormalities, including
hyperbilirubinemia, and elevated transaminases.
Other
Hyperammonemia, diabetic ketoacidosis, and hyperlipidemia
including hypertriglyceridemia and hypercholesterolemia
Immunogenicity
As with all therapeutic proteins, there is a potential
for immunogenicity, defined as development of binding and/or neutralizing
antibodies to the product.
Elspar is a bacterial protein and can elicit antibodies
in patients treated with the drug. In 2 prospectively designed clinical trials
(N=59 and 24), approximately one quarter of the patients developed antibodies
that bound to Elspar as measured by enzyme-linked immunosorbent assays (ELISA).
Clinical hypersensitivity reactions to Elspar in studies were common ranging from
32.5% to 75%. In these studies, concomitant medications and dosing schedules
varied. Patients with hypersensitivity reactions were more likely to have
antibodies than those without hypersensitivity reactions. Hypersensitivity
reactions have been associated with increased clearance of Elspar. Incidence of
antibody formation was lower upon first administration of Elspar than second administration.
The frequency of antibody formation in adults relative to children is unknown. There
is insufficient information to comment on neutralizing antibodies; however,
higher levels of antibody correlated with a decrease in asparaginase activity.
The detection of antibody formation is highly dependent
on the sensitivity and specificity of the assay, and the observed incidence of
antibody positivity in an assay may be influenced by several factors including
sample handling, concomitant medications and underlying disease. Therefore,
comparison of the incidence of antibodies to Elspar with the incidence of
antibodies to other products may be misleading.
DRUG INTERACTIONS
No formal drug interaction studies between Elspar and
other drugs have been performed.