It is important to note that standard cancer treatments (surgery, chemo/radiation) can always be optimized and improved and many examples exist of life enhancing advancements for almost every type of cancer.
Statistical modeling in pharmaceutical research and development.
Optimizing Chemotherapy for AML Subtypes
1. Optimizing Chemotherapy:
It is important to note that standard cancer treatments (surgery, chemo/radiation) can always be
optimized and improved and many examples exist of life enhancing advancements for almost
every type of cancer.
Since the genetic subtypes of each cancer usually have varying prognoses and responses to
treatment, so it is important to determine the specific subtype for each patient. The subtypes of
most cancers are determined by the types of cell surface proteins (immunophenotyping) and the
chromosomal changes (translocations).
Therefore, it is fundamental that the treatment you engage in is optimized for your particular
molecular signature and not just the most common form of treatment available in your area.
The following section shows how the standard treatment for Acute Myeloid Leukemia can be
optimized.
The Five-year survival for standard AML treatment with 7+3 (cytarabine & daunorubicin) varies
from 15-70% and relapse rates vary from 78-33%, depending on the genetic subtype (Grimwade
et al. (1998).
The effectiveness the standard treatment (referred to as 7+3) has on patients with specific genetic
signatures is indicated below.
The prognostic chromosomal rearrangements for standard treatment of AML (7+3) are as
follows:
Good Prognosis:
AML cases with chromosomal rearrangements such as t(8;21), t(15;17), inv(16) have a five year
survival rate of 70% and a relapse rate of 33%.
Intermediate Prognosis:
AML cases with chromosomal rearrangements such as normal, +8, +21, +22, del(7q), del(9q) or
abnormal 11q23, have a five year survival rate of 48% and a relapse rate of 50%.
Poor Prognosis:
AML cases with chromosomal rearrangements such as -5, -7, del(5q), abnormal 3q or complex
cytogenetics, have a five year survival rate of 15% and a relapse rate of 78%
As you can see, the outlook for patients with poor prognosis rearrangements is not good.
The next section outlines a significant improvement in treating these patients.
Concerns with Standard Treatment for AML Patients Harboring Abnormal Chromosome
3q:
Genetically, AML is a heterogeneous disease with 40% of cases based on primary chromosome
translocations or inversions that encode fusion proteins (Shing et al., 2007).
2. Based on cytogenetic and immune based data, patients with an abnormal 3q chromosome most
likely have the MEL1S fusion protein driving their disease. The loss of the p53 tumor suppressor
gene usually accompanies this genetic rearrangement. Since the standard treatment was not
designed to target cells expressing this fusion protein, it is unlikely to achieve remission in this
case.
Furthermore, the 7+3 regime is only effective when the chemotherapeutic agents are combined in
a specific ratio. Since the genes that metabolize these agents as well as individual patient's health
varies greatly, maintaining this narrow therapeutic window is challenging.
Improvements to Treatment for AML (Optimized Chemotherapy):
In CPX-351,cytarabine and daunorubicin are encapsulated within liposomes in a 5:1 ratio,
allowing for the synergistic drug ratio to be maintained in the blood plasma for 24 hours post-
injection, which is a significant improvement.
Results from pre-clinical studies have shown that despite using sub-MTD daunorubicin doses,
CPX-351 exhibited superior therapeutic activity, maintenance of synergistic drug ratios in bone
marrow, and high proportions of long-term survivors compared to standard free-drug cocktails
(Lim et al., 2010).
Significance:
The significance of this example is that it indicates how a simple variation in a common
procedure, such as maintaining a synergistic 5:1 drug ratio, results in superior therapeutic
activity, maintenance of synergistic drug ratios in bone marrow, and high proportions of long-
term survivors compared to standard free-drug cocktails.
While this variation may not appear significant in long-term management of AML, it is
important to note that with every therapeutic approach and type of cancer examined, we have
identified many similar examples of life enhancing updates and improvements.
If you have AML and are interested in receiving CPX-351, click on the following link to
contact Celator:
http://www.celatorpharma.com/new/products_cpx351.html