Dried Blood SPOT Analysis of Everolimus in Cancer Patients (SPOT-study)
Status:
Completed
Trial end date:
2017-01-01
Target enrollment:
Participant gender:
Summary
Everolimus shows a large interpatient variability with fixed dose administration. These very
different exposure levels between individuals can result in supratherapeutic or
subtherapeutic exposure levels and consequently in over- or undertreatment, respectively.
Dose individualization based on the measured drug concentration could theoretically result in
less toxicity and more efficacy.
Nowadays everolimus exposure is determined by everolimus concentration in whole blood.
Therefore, a vena puncture is always necessary. This is invasive and requires patients to
come to the hospital. It would be convenient for patients to have their everolimus blood
concentration determined by dried blood spot (DBS) analysis. With DBS only a single drop of
blood from the finger is necessary, which can be done at home and sent by regular mail for
analysis. Previous studies have shown the feasibility of this approach. In patients with
cancer treated with everolimus 10mg once daily, the correlation between everolimus DBS
concentrations and whole blood concentration is yet unknown. Therefore, the investigators
want to determine the everolimus concentration collected with DBS from a finger prick with
everolimus concentration from whole blood and everolimus concentration collected with DBS
from whole blood.
In addition, possibly a relatively high everolimus concentration in saliva could be
correlated with the incidence and severity of oral mucositis. Determination of drug
concentration in saliva has also been proven to be feasible before.
Therefore, in this study the investigators want to determine whether the everolimus
concentration in saliva correlates with the incidence of oral mucositis and how everolimus
concentration in saliva correlates with everolimus concentration in whole blood.