Transcript Poster

Pharmacokinetics of Vancomycin in Adult
Oncology Patients
Hadeel Al-Kofide MS.c; Iman Zaghloul PhD; and Lamya Al-Naim PharmD
Department of Clinical Pharmacy, College of Pharmacy. King Saud University
Results
Introduction
Table I: Patients’ Demographic Data
Methicillin-resistance Staphylcoccus aureus (MRSA) account for up
to 50% of S.aureus infection
 Vancomycin is an integral part of the management of infections in
cancer patients when MRSA is suspected due to the emergence of
such resistant organism & the absence of an alternative in these
patients
 Studies have shown sub-therapeutic levels of vancomycin in such
population. Therefore, higher dosages have been proposed to ensure
optimal drug concentrations
Data presented as Mean ± Standard Deviation
Data presented as Mean ± Standard Deviation
 Gram-positive infections are prevalent among cancer patients, and
Cancer
Characteristics
Group
NonCancer
Group
Pvalue
Cancer
Characteristics
Group
0.526
Dose mg
986.1 ± 159.8 1000 ± 353.6 0.884
Frequency hr
13.3 ± 3.9
Age
43.4 ± 22.1
48.5 ± 20.2
Height, cm
161.1 ± 11.7
164.9 ± 10.1 0.349
TBW, kg
66.8 ± 17.1
68.9 ± 14
Objectives
 The aim of the study is to evaluate the effects of certain clinical
factors on the kinetics of this drug in cancer patients and to find
potential predictive factors for dosage individualization. In addition,
to study its kinetics in Saudi non-cancer patients to be used for
comparison with previous literature.
BSA
Study Design: retrospective study
Study Setting and Time: the data were collected in King Khalid
University Hospital (KKUH) for the year 2005
Inclusion Criteria: all adult inpatients on vancomycin with the
availability of necessary data as vancomycin peak levels
Exclusion Criteria: patients with acute or chronic renal failure and
lack of required information
 A total of 260 adult inpatients admitted in KKUH for the year 2005
on vancomycin were screened for eligibility
 From those patients, 31 were chosen for analysis others were
excluded due to lack of necessary data as vancomycin peak levels
and acute or chronic renal failure
 Two groups of patients were assigned, 18 cancer & 13 non-cancer
patients
 Measurement of the peak & trough levels were conducted after the
third dose of the initial dosing regimen & Vancomycin
pharmacokinetic parameters were calculated
 The data were coded & entered in to a Statistical Package for Social
Sciences (SPSS)
 Pharmacokinetic calculation was conducted on Excel program
 Independent sample t test was done to compare values between study
groups; with a statistical significance level < 0.05
 Correlation between different parameters was done using Pearson
correlation.
1.7 ± 0.25
11.5 ± 1.7
Pvalue
0.129
58.4 ± 10.6
1.7 ± 0.19
19.1 ± 6.3
27.2 ± 10.9
0.027
0.56
0.5
7.1 ± 5.5
Trough mg/L
8.5 ± 4.5
0.458
Data presented as Mean ± Standard Deviation
Data presented as Mean ± Standard Deviation
Albumin, g/L
Pvalue
26.1 ± 6.0 29.5 ± 6.7
0.155
62.4 ± 6.2 66.1 ± 9.5
0.206
Serum Creatinine,
64.2 ± 21
0.073
CrCl, ml/min
patients with cancer compared to literature on general population
 When comparing with our control there was a 50% increase in
the clearance
 Vancomycin clearance in the control Saudi group was increased
by 32% when compared to published literature
 Vancomycin dose required for such patients was double the
usual dose (about 60 mg/kg/day)
& the existence of neutropenia among other clinical parameters
analyzed, had no significant correlation with or effect
on vancomycin disposition
 Except for creatinine clearance which would be expected in a
PK
parameter
Cancer
Group
0.14 ± 0.1
K, hrˉ¹
NonCancer
Group
P-value
0.14 ± 3.9
0.947
Conclusions
 Standard dosage regimens of vancomycin, in oncology patients,
Total Protein, g/L
umol/L
80% increase in vancomycin clearance in
drug eliminated mainly through renal excretion.
Table IV: Vancomycin Pharmacokinetic Parameters
NonCancer
Cancer
Group
Group
 There was about
 Critical characteristics of patients with cancer such as diagnosis,
Table II: Patients’ Clinical Data,
Characteristics
Methods
55.9 ± 12.5
NonCancer
Group
0.714
Peak mg/L
IBW, kg
Discussion
Table III: Vancomycin Regimen
83.1 ± 35.2
105.5 ± 62 87.2 ± 27.5
0.331
t1/2, hr
8.6 ± 7.1
5.4 ± 1.9
0.111
Vd, L
70 ± 45
31.1 ± 8.3
0.002
Cl, ml/min
110.1 ± 42
71.2 ± 22.2
0.005
continue to be used although they may often be suboptimal owing
to the greater Cl & Vd found in this target population
 Cancer patients may require higher than usual dosing regimens to
ensure optimal therapeutic concentrations
 TDM of vancomycin is strongly recommended in this population
 More care should be taken when giving vancomycin to cancer
patients due to their high clearance values.
1.2
1.08
0.98
1
Figure I: Comparison with
Literature
HM, Haematological Malignancies. Cl,
Clearance. CrCl, Creatinine Clearance.
Vd, Volume of Distribution. TBW, Total
Body Weight
1.01
0.86
0.8
0.6
1.15
0.65
Cl/CrCl
0.7
Vd/TBW
0.47
0.4
We would like to thank the departments of oncology, medical
records and pharmacy staff at KKUH who helped us during our
investigation.
0.2
0
General
Population
Non-Cancer Literature on
Group
HM
Acknowledgments
Cancer
Group