On Location ASH Meeting on Hematologic Malignancies
Shared-Care Model of PostConsolidation Care Reduces Travel
Burden for AML Patients
In Canada, investigators have been evaluating a shared-care model for acute myeloid
leukemia (AML) post-consolidation supportive therapy. The collaborative program
permits patients to visit local centers, thus
avoiding prolonged hospitalization or long
commutes for care. Samantha Hershenfeld from the Princess Margaret Cancer
Centre in Ontario, who presented this
research at the 2015 ASH Meeting on Hematologic Malignancies, told ASH Clinical
News that the center “is very gung ho about
this model.”
“AML usually requires intensive induction and consolidation chemotherapy.
What our group and others have shown in
the past is that you can actually deliver that
consolidation care on an outpatient basis at
quaternary centers,” Ms. Hershenfeld said.
Lyophilized Powder for Solution for Intravenous Injection
ADVERSE REACTIONS
Brief Summary of Prescribing Information: Please see
package insert for full Prescribing Information.
Common adverse reactions observed in greater than 5% of
subjects in the clinical trial were development of inhibitors to
porcine factor VIII.
INDICATIONS AND USAGE
OBIZUR, Antihemophilic Factor (Recombinant), Porcine
Sequence, is a recombinant DNA derived, antihemophilic
factor indicated for the treatment of bleeding episodes in
adults with acquired hemophilia A.
Limitations of Use:
Clinical Trials Experience
Because clinical trials are conducted under widely varying
conditions, adverse reaction (AR) rates observed in the clinical
trials of a drug cannot be directly compared to rates in the
clinical trials of another drug and may not reflect the rates
observed in clinical practice.
CONTRAINDICATIONS
The safety and efficacy of OBIZUR was evaluated in a multicenter, prospective, open-label, clinical trial that investigated
adult patients with acquired hemophilia A. Twenty-nine adult
subjects were enrolled in the study, received at least one dose
of OBIZUR and were evaluable for safety. Of the 29 adult
subjects, 10 were between the ages of 40 and 65, and 19 were
65 years of age or older (18 Caucasian, 6 African-American,
and 5 Asian). Ten (34%) subjects were female.
OBIZUR is contraindicated in patients who have had lifethreatening hypersensitivity reactions to OBIZUR or its
components (including traces of hamster proteins).
The most frequently reported adverse reaction in patients
with acquired hemophilia A was the development of inhibitors
to porcine factor VIII.
WARNINGS AND PRECAUTIONS
Immunogenicity
• Safety and efficacy of OBIZUR has not been established in
patients with baseline anti-porcine factor VIII inhibitor titer
greater than 20 BU.
• OBIZUR is not indicated for the treatment of congenital
hemophilia A or von Willebrand disease.
Hypersensitivity Reactions
Hypersensitivity reactions can occur with OBIZUR. OBIZUR
contains trace amounts of hamster proteins. Early signs of
allergic reactions, which can progress to anaphylaxis, include
angioedema, chest-tightness, dyspnea, hypotension,
wheezing, urticaria, and pruritus. Immediately discontinue
administration and initiate appropriate treatment if allergic
or anaphylactic-type reactions occur.
Inhibitory Antibodies
Inhibitory antibodies to OBIZUR have occurred. Monitor
patients for the development of antibodies to OBIZUR by
appropriate assays. If the plasma factor VIII level fails to
increase as expected, or if bleeding is not controlled after
OBIZUR administration, suspect the presence of an antiporcine factor VIII antibody. If such inhibitory antibodies
to anti-porcine factor VIII are suspected and there is a
lack of clinical response, consider other therapeutic options.
Monitoring Laboratory Tests
• Perform one-stage clotting assay to confirm that adequate
factor VIII levels have been achieved and maintained.
– Monitor factor VIII activity 30 minutes and 3 hours after
initial dose.
– Monitor factor VIII activity 30 minutes after
subsequent doses.
• Monitor the development of inhibitory antibodies to
OBIZUR. Perform a Nijmegen Bethesda inhibitor assay if
expected plasma factor VIII activity levels are not attained
or if bleeding is not controlled with the expected dose of
OBIZUR. Use Bethesda Units (BU) to report inhibitor levels.
All subjects were monitored for development of inhibitory
antibodies to OBIZUR using the Nijmegen modification of the
Bethesda inhibitor assay. A subject was considered to have
developed an OBIZUR inhibitor if the titer was ≥0.6 Bethesda
Units (BU)/mL.
Of the 29 subjects treated with OBIZUR, 19 subjects were
negative for anti-porcine factor VIII antibodies at baseline.
Five of the 19 (26%) developed anti-porcine factor VIII
antibodies following exposure to OBIZUR. Of the 10 subjects
with detectable anti-porcine factor VIII antibodies at baseline,
2 (20%) experienced an increase in titer and eight (80%)
experienced a decreasing to a non-detectable titer.
All subjects were also monitored for development of binding
antibodies to baby hamster kidney (BHK) protein by a
validated sequential ELISA (enzyme-linked immunosorbent
assay). No patients developed de novo anti-BHK antibodies.
The detection of antibody formation is highly dependent on
the sensitivity and specificity of the assay. Additionally, the
observed incidence of antibody (including neutralizing
antibody) positivity in an assay may be influenced by several
factors, including assay methodology, sample handling,
timing of sample collection, concomitant medications, and
underlying disease. For these reasons, comparison of the
incidence of antibodies to OBIZUR with the incidence of
antibodies to other products may be misleading.
Baxalta and Obizur are trademarks of Baxalta Incorporated.
Manufactured by:
Baxalta US Inc.
Westlake Village, CA 91362 USA
U.S. License No. 140
“On the flipside, that also requires patients
to travel often very long distances back
and forth for frequent treatments at the
hospital.”
To help solve this problem and reduce
travel burden for patients with AML,
clinicians at Princess Margaret Cancer
Centre developed a shared-care model in
which patients receive their consolidation
chemotherapy for AML at the specialized
quaternary care center, but receive postconsolidation supportive care (including blood checks, transfusions,
and treatment for febrile neutropenia) at their local hospitals.
Between 2009 and 2013, 73
patients with AML (n=61) or acute
promyelocytic leukemia (APL)
(n=12) who had received induction and consolidation therapy at
a quaternary care center (Princess
Margaret) were treated under
the shared-care model, receiving
post-consolidation care after first
complete remission at one of 14
local centers.
AML patients
who received
post-consolidation care at
a local center
had similar
outcomes to
those treated
at a specialized center.
These 14 centers were regional cancer centers staffed by
oncologists and/or hematologists
experienced in the management
of cytopenias and febrile neutropenia, but which did not provide
induction or consolidation chemotherapy for AML.
Patients were seen at least
weekly as outpatients at these
hospitals while recovering from
their consolidation chemotherapy.
Centers were located a median of
70 km (range = 36-190 km) from
the quaternary center. Each local
center treated a median of two
patients (range = 1-19 patients)
during the time frame evaluated.
“In terms of demographics, the
[shared-care] group was actually no different in age, gender,
USBS/MG114/15-0031
October 2015