Most cancer clinical studies exclude patients with co-morbidities,
active or recent malignancies, organ dysfunction or poor performance
A novel study
at The University of Texas MD Anderson Cancer Center revealed some
patients with acute myeloid leukemia (AML) and myelodysplastic syndrome
(MDS), who traditionally could not be considered for clinical trials,
responded well and were safely treated in this setting.
‘Some leukemia patients with existing medical conditions could benefit from participation in clinical trials.’
The study, led by Guillermo Garcia-Manero, professor of
Leukemia, followed 109 patients with AML and MDS undergoing treatment
with azacitidine (AZA) and vorinostat. Research results were presented at the 58th Annual Meeting of the American Society for Hematology
in San Diego.
"Patients who potentially could benefit most from participation in
clinical trials due to poor prognoses often are not included based on
eligibility criteria, such as existing medical illnesses," said Garcia-Manero. "How these criteria protect patients is
unclear. Although some are based on clinical reasoning, it seems these
criteria are in place more to protect the drug or intervention being
studied rather than the patient."
The study initially enrolled 30 patients age 17 and older who had
not previously been treated for AML or MDS. Patients eligible for the
study had either poor performance, poor renal or hepatic function or any
other active systemic disorder such as other cancer.
Sixty-day survival was 83% with low-grade gastrointestinal
side effects reported. The study was expanded to include an additional
79 patients. 60-day survival for the second group was 79% with
a median overall survival of 7.6 months. The average event-free
survival was 4.5 months. Again, only low-grade gastrointestinal side
effects were observed.
The study was designed with "stopping rules" that included
monitoring of side effects and complete response rates. Patients were
immediately placed on another therapy if their assigned therapy did not
indicate there would be a complete response within a 60-day period. To
define the minimum expected survival and response rates that would
trigger the stopping rules, researchers relied on prior data of 181
patients previously treated at MD Anderson.
"Participation in clinical trials is fundamental for the development
of new therapeutic interventions," said Guillermo Montalban-Bravo,
fellow in Leukemia, a research team member. "Despite this need,
only 3-5% of patients with cancer treated in the U.S.
currently are enrolled in clinical trials."
The study points to further evaluation of standard exclusion
criteria, potentially increasing the pool of patient likely to benefit
from therapy, with the aim of future larger clinical trials specifically
treating patients with AML and MDS.