Cyclophosphamide Concentrations Research Articles

Multicenter study of environmental contamination with antineoplastic drugs in 33 Canadian hospitals

No occupational exposure limit exists for antineoplastic drugs. The main objective of this study was to describe environmental contamination with cyclophosphamide, ifosfamide and methotrexate in pharmacy and patient care areas of Canadian hospitals in 2012. The secondary objective was to compare the 2012 environmental monitoring results with the 2008-2010 results. Six standardized sites in the pharmacy and six sites on patient care areas were sampled in each participating center. Samples were analyzed for the presence of cyclophosphamide, ifosfamide and methotrexate by UPLC-MS-MS. The limit of detection (LOD) was 1.8 pg/cm² for cyclophosphamide, 2.2 pg/cm² for ifosfamide and 8.0 pg/cm² for methotrexate. The comparison of surface contamination between the 2008-2010 and 2012 studies was made with the 75th percentile of cyclophosphamide concentration. A total of 33 hospitals participated in the study and 363 samples were collected. Overall, 40 % (147/363) of the samples were positive for cyclophosphamide, 18 % (68/363) were positive for ifosfamide and 5 % (17/363) were positive for methotrexate. In 2012, the 75th percentile value of cyclophosphamide surface concentration was of 9.4 pg/cm², which is four times lower than the 2008-2010 75th percentile of 40 pg/cm². In both studies, the 75th percentile for ifosfamide and methotrexate concentration was lower than the LOD. Surface contamination by cyclophosphamide, ifosfamide and methotrexate in Canadian hospitals is improving both in terms of the proportions of positive samples and in terms of the surface concentration of antineoplastic drugs. A local 75th percentile value should be use to assess local contamination and interpret local results.

Association between Occupational Exposure and Control Measures for Antineoplastic Drugs in a Pharmacy of a Hospital

To investigate the association between occupational contamination and exposure levels to antineoplastic drugs and the application of control measures in a hospital work environment. Wipe samples of equipments were collected at a hospital in Osaka Prefecture, Japan, from 2007 to 2011. These samples were subjected to measurements of cyclophosphamide (CP), gemcitabine (GEM), platinum-containing drugs (Pt), and fluorouracil (5FU). Additionally, 24-h urine samples were collected from pharmacists who handled antineoplastic drugs, which were analyzed for CP and alpha-fluoro-beta-alanine (AFBA). The application of control measures was scored according to a checklist, which consisted of the following five items: safety equipment and maintenance, training and documentation, devices for safe handling, personal protective equipment, and emergency care. The aim was to obtain a score of 80%. The median CP, GEM, and 5FU concentrations of all wipe samples were significantly lower during the period when the mean score was >80% (attainment period) versus when the mean score was ≤80% (nonattainment period; all P < 0.001, Mann-Whitney's U-test). Additionally, the median urinary CP and AFBA concentrations of pharmacists during the attainment period tended to be lower than that of those during the nonattainment period (P = 0.061 and 0.061, respectively, using Mann-Whitney's U-test). Contamination and levels of exposure to antineoplastic drugs decreased with a score higher than 80%. The scores of the items on the checklist appeared to adequately reflect the condition of the control measures, as increases in all five items were associated with reductions in the contamination by and levels of exposure to all drugs.

Determination of exposure of dispensary drug preparers to cyclophosphamide by passive sampling and liquid chromatography with tandem mass spectrometry

To determine cyclophosphamide exposure to preparers during tablet crushing and subsequent handling by analyzing indoor air collected using a high-performance volatile organic compounds-solvent desorption (VOC-SD) passive air sampler. The passive sampler was taped to the mask over the mouth of the preparer and indoor air was collected during crushing and preparation of cyclophosphamide tablets (Endoxan®). After collection, the carbon molecular sieve adsorbent of the passive sampler was placed in a centrifuge tube, and 1 mL of carbon disulfide was used to elute cyclophosphamide from the adsorbent. Liquid-liquid extraction with 1 mL of water was performed, and the aqueous phase was used as the test solution. Cyclophosphamide concentration was determined by liquid chromatography with ultraviolet and tandem mass spectrometry detection. Cyclophosphamide concentration was detected in the range of 7.6-157.7 ng/sampler. Our results showed that low-level exposure occurred near the mouth of the preparer, which could present risks for long-term exposure, especially if combined with multiple toxic drug exposures. The anticancer drug monitoring methodology described here is a simple exposure assessment that can be used to ensure the safety of hospital pharmacy tablet preparers. Furthermore, since the anticancer drug exposure risk is very high for preparers, preparation should be in hood or with face mask.

Effects of Aprepitant on Drug Metabolism in Lymphoma Patients Receiving Multi-Day Chemotherapy Regimen of Cyclophosphamide, Doxorubicin, Vincristine, Prednisone, + Rituxan (R/CHOP): Randomized, Cross-Over Study

Abstract 1613Chemotherapy-induced nausea and vomiting (CINV) is a frequent adverse event that can impair the quality of life in cancer patients (pts). In pts receiving cyclophosphamide (CP) and doxorubicin-based regimen, the combination of dexamethasone (dexa) and 5-HT3 receptor antagonists (5-HT3 RA) is very effective in acute emesis, however, control of delayed-emesis remains poor. The neurotransmitter substance P appears to be involved in both the acute and delayed-phases. Aprepitant, a substance P/ neurokinin (NK)-1 receptor antagonist, when combined with 5-HT3 RA and dexa, has been shown to prevent acute and delayed CINV associated with moderately and highly emetogenic chemotherapy (CT). However, aprepitant is a moderate inhibitor of cytochrome p-450 system, primarily via CYP 3A4, a liver microsome that also metabolizes several CT agents, including CP to some extent, its use has been approached with caution. This study evaluated the effect of aprepitant on drug metabolism in lymphoma pts receiving (R)CHOP which contains several agents that can be affected by this pathway. This randomized, cross-over trial was designed to enroll 18 evaluable pts; the absence of pharmacokinetic (PK) drug interactions can be determined if the 90% confidence interval (CI) of the geometric mean AUC ratio between 2 groups is within 80 to 125%. All pts received standard anti-emetic regimen of 5-HT3 RA (ondansetron) and steroids. The pts were randomized into 2 groups. Group 1 received aprepitant in cycle-1 and not in cycle-2. Group 2 received aprepitant in cycle-2 and not in cycle-1. The cross-over design was used to minimize inter-patient PK variability and drug cumulative effects, by using the patients as their own control. For breakthrough N/V, medications that are substrates, inducers, or inhibitors of CYP 3A4 were not permitted. Blood samples were drawn during and post CT infusion in both groups at following time points: baseline before the start of treatment, 30, 60, 75, and 90 minutes, and 2, 4, 6, 8, and 24 hours from the start of CP infusion. Samples were analyzed for concentration of CP, vincristine, and prednisone, and their active metabolites. Eighteen of the 23 pts enrolled completed 2 cycles and were evaluable for PK analysis. Both groups were comparable with regards to demographics. The data for AUC for parent drug and metabolites are shown below.Geometric Mean AUC 0–24hr [(μg/mL*hr)/mL]Ratio of Geometric Mean AUC 0–24hr Analyte in Aprepitant Treatment to Control (90% CI)AprepitantControl1.20 (1.08–1.33)CP300.0250.52-deCl-CP4.560.75 (0.65–0.86)4-OH-CP3.940.97 (0.83–1.13)PR€2872651.08 (1.02–1.15)PL€441638171.16 (1.01–1.32)VC€41391.04 (0.82–1.33)€(ng/mL*hr) Abbreviations: CP, Cyclophosphamide; 2-deCl-CP, 2-dechloro-cyclophosphamide; 4-OH-CP, 4-hydroxy-cyclophosphamde, PR; prednisone, PL; prednisolone, VC; vincristineThe AUC for active metabolite (4-OH-CP) was within the pre-defined range; but there was some increase in the parent CP and some decrease in the toxic metabolite (2-deCl-CP). The AUC for PR was within the defined range. Although, there was some increase in the active metabolite PL, the blood sugar levels were not significantly different in 2 groups (mean change 43% vs 37%). The Functional Living Index-Emesis (FLIE) scores for N/V were not significantly different. There were no serious adverse events related to aprepitant. Conclusions:Administration of aprepitant with (R)CHOP resulted in minor changes in the levels of parent drugs and/or metabolites; which are unlikely to have significant clinical impact. Disclosures:Vadhan-Raj:Merck: Research Funding. Spasojevic:Merck: Research Funding. Neelapu:celgene: Research Funding.

Potential Contribution of Cytochrome P450 2B6 to Hepatic 4-Hydroxycyclophosphamide Formation In Vitro and In Vivo

Results from retrospective studies on the relationship between cytochrome P450 (P450) 2B6 (CYP2B6) genotype and cyclophosphamide (CY) efficacy and toxicity in adult cancer patients have been conflicting. We evaluated this relationship in children, who have faster CY clearance and receive different CY-based regimens than adults. These factors may influence the P450s metabolizing CY to 4-hydroxycyclophosphamide (4HCY), the principal precursor to CY's cytotoxic metabolite. Therefore, we sought to characterize the in vitro and in vivo roles of hepatic CYP2B6 and its main allelic variants in 4HCY formation. CYP2B6 is the major isozyme responsible for 4HCY formation in recombinant P450 Supersomes. In human liver microsomes (HLM), 4HCY formation correlated with known phenotypic markers of CYP2B6 activity, specifically formation of (S)-2-ethyl-1,5-dimethyl-3,3-diphenyl pyrrolidine and hydroxybupropion. However, in HLM, CYP3A4/5 also contributes to 4HCY formation at the CY concentrations similar to plasma concentrations achieved in children (0.1 mM). 4HCY formation was not associated with CYP2B6 genotype at low (0.1 mM) or high (1 mM) CY concentrations potentially because CYP3A4/5 and other isozymes also form 4HCY. To remove this confounder, 4HCY formation was evaluated in recombinant CYP2B6 enzymes, which demonstrated that 4HCY formation was lower for CYP2B6.4 and CYP2B6.5 compared with CYP2B6.1. In vivo, CYP2B6 genotype was not directly related to CY clearance or ratio of 4HCY/CY areas under the curve in 51 children receiving CY-based regimens. Concomitant chemotherapy agents did not influence 4HCY formation in vitro. We conclude that CYP2B6 genotype is not consistently related to 4HCY formation in vitro or in vivo.

Early embryonic sensitivity to cyclophosphamide in cardiac differentiation from human embryonic stem cells

hESCs (human embryonic stem cells) can differentiate into tissue derivatives of all three germ layers in vitro and mimic the development of the embryo in vivo. In this study, we have investigated the potential of an hESC-based assay for the detection of toxicity to cardiac differentiation in embryonic development. First of all, we developed the protocol of cardiac induction from hESCs according to our previous work and distinguished cardiac precursor cells and late mature cardiomyocytes from differentiated cells, demonstrated by the Q-PCR (quantitative real-time PCR), immunocytochemistry and flow cytometry analysis. In order to test whether CPA (cyclophosphamide) induces developmental and cellular toxicity in the human embryo, we exposed the differentiating cells from hESCs to CPA (a well-known proteratogen) at different stages. We have found that a high concentration of CPA could inhibit cardiac differentiation of hESCs. Two separate exposure intervals were used to determine the effects of CPA on cardiac precursor cells and late mature cardiomyocytes respectively. The cardiac precursor cells were sensitive to CPA in non-cytotoxic concentrations for the expression of the cardiac-specific mRNA markers Nkx2.5 (NK2 transcription factor related, locus 5), GATA-4 (GATA binding protein 4 transcription factor) and TNNT2 (troponin T type 2). Non-cytotoxic CPA concentrations did not affect the mRNA markers' expression in late mature cardiomyocytes, indicating that cardiac precursors were more sensitive to CPA than late cardiomyocytes in cardiogenesis. We set up the in vitro developmental toxicity test model so as to reduce the number of test animals and expenses without compromising the safety of consumers and patients. Furthermore, such in vitro methods may be possibly suited to test a large number of chemicals than the classical employed in vivo tests.

Pharmacokinetics of Cyclophosphamide after Oral and Intravenous Administration to Dogs with Lymphoma

Cyclophosphamide is an alkylating chemotherapeutic drug administered i.v. or p.o.. It is currently assumed that exposure to the active metabolite, 4-hydroxycyclophosphamide (4-OHCP), is the same with either route of administration. To characterize the pharmacokinetics of cyclophosphamide and 4-OHCP in dogs with lymphoma when administered p.o. or i.v.. Sixteen client-owned dogs with substage A lymphoma were enrolled in the study. Eight dogs received cyclophosphamide i.v. and 8 received it p.o.. Prospective randomized clinical trial was performed. Blood was collected from each dog at specific time points after administration of cyclophosphamide. The serum was evaluated for the concentration of cyclophosphamide and 4-OHCP with mass spectrometry and liquid chromatography. Drug exposure to cyclophosphamide measured by area under the curve (AUC)(0-inf) is significantly higher after intravenous administration (7.14 ± 3.77 μg/h/mL) compared with exposure after oral administration (P-value < .05). No difference in drug exposure to 4-OHCP was detected after i.v. (1.66 ± 0.36 μg/h/mL) or p.o. (1.42 ± 0.64 μg/h/mL) administered cyclophosphamide. Drug exposure to the active metabolite 4-OHCP is equivalent after administration of cyclophosphamide either p.o. or i.v..

Pharmacokinetics of cyclophosphamide and its metabolites in paediatric patients receiving high-dose myeloablative therapy

IntroductionIn order to better understand the impact of high-dose on the pharmacokinetics and metabolism of cyclophosphamide, a pharmacological study was performed in children with malignant mesenchymal tumours with metastatic disease. MethodsPatients received four courses of chemotherapy including two courses of cyclophosphamide. Plasma concentrations of cyclophosphamide and the metabolites 4-ketocyclophosphamide, dechloroethylcyclophosphamide and carboxyphosphamide were determined on days 1, 2 and 3 of each course. A population pharmacokinetic model for cyclophosphamide was developed using non-linear mixed effects modelling and metabolite AUC values were compared between days and courses. ResultsData were available on 21 cyclophosphamide courses from 15 patients. A one compartment model, incorporating a term in surface area for both CL and V, best described cyclophosphamide pharmacokinetics. Typical CL and V on day 1 of treatment for a patient with a SA of 1.4m2 were 4.3L/h and 28.5L, respectively. On days 2 and 3 CL increased by 88% (95% CI, 72–105%) and 125% (95% CI, 108–145%) over day 1 levels; V increased by 14% (95% CI, 5–23%) on days 2 and 3. V tended to be larger for males than similarly sized females but no effect of age was found upon CL or V. Significant increases in metabolite AUCs were observed on days 2 and 3 compared to day 1 and a significant increase in CXCP AUC from course 1 to course 3. ConclusionAdministration of high-dose cyclophosphamide over several days results in an increase in metabolism, possibly by induction of the activation pathway. This induction is effectively reversed following a four week period between cyclophosphamide doses. The degree of intersubject variation in cyclophosphamide elimination is largely accounted for by body surface area and is less than previously reported.

A study protocol for the evaluation of occupational mutagenic/carcinogenic risks in subjects exposed to antineoplastic drugs: a multicentric project

BackgroundSome industrial hygiene studies have assessed occupational exposure to antineoplastic drugs; other epidemiological investigations have detected various toxicological effects in exposure groups labeled with the job title. In no research has the same population been studied both environmentally and epidemiologically. The protocol of the epidemiological study presented here uses an integrated environmental and biological monitoring approach. The aim is to assess in hospital nurses preparing and/or administering therapy to cancer patients the current level of occupational exposure to antineoplastic drugs, DNA and chromosome damage as cancer predictive effects, and the association between the two.Methods/DesignAbout 80 healthy non-smoking female nurses, who job it is to prepare or handle antineoplastic drugs, and a reference group of about 80 healthy non-smoking female nurses not occupationally exposed to chemicals will be examined simultaneously in a cross-sectional study. All the workers will be recruited from five hospitals in northern and central Italy after their informed consent has been obtained.Evaluation of surface contamination and dermal exposure to antineoplastic drugs will be assessed by determining cyclophosphamide on selected surfaces (wipes) and on the exposed nurses' clothes (pads). The concentration of unmetabolized cyclophosphamide as a biomarker of internal dose will be measured in end-shift urine samples from exposed nurses.Biomarkers of effect and susceptibility will be assessed in exposed and unexposed nurses: urinary concentration of 8-hydroxy-2-deoxyguanosine; DNA damage detected using the single-cell microgel electrophoresis (comet) assay in peripheral white blood cells; micronuclei and chromosome aberrations in peripheral blood lymphocytes. Genetic polymorphisms for enzymes involved in metabolic detoxification (i.e. glutathione S-transferases) will also be analysed.Using standardized questionnaires, occupational exposure will be determined in exposed nurses only, whereas potential confounders (medicine consumption, lifestyle habits, diet and other non-occupational exposures) will be assessed in both groups of hospital workers.Statistical analysis will be performed to ascertain the association between occupational exposure to antineoplastic drugs and biomarkers of DNA and chromosome damage, after taking into account the effects of individual genetic susceptibility, and the presence of confounding exposures.DiscussionThe findings of the study will be useful in updating prevention procedures for handling antineoplastic drugs.

Validation and application of Drosophila melanogaster as an in vivo model for the detection of double strand breaks by neutral Comet assay

Comet assay under neutral conditions allows detection of DNA double-strand breaks (DSBs), which has consequence to genome instability and carcinogenesis. The present study aims to validate the neutral Comet assay for genotoxicity assessment in Drosophila melanogaster (Oregon R +) with three well known DSBs inducers i.e. cyclophosphamide (CP), bleomycin (BLM), cisplatin (CPT) and subsequently its efficacy in detecting DSBs in the organism exposed to a well known environmental chemical, chromium [Cr(VI)]. Third instar larvae of D. melanogaster were fed different concentrations of BLM, CPT and CP (50.0–200.0 μg/ml) or Cr(VI) (5.0–20.0 μg/ml) mixed standard Drosophila food for 48 h. Neutral Comet assay was performed in cells of mid gut and brain from control and treated larvae. Our results show a dose-dependent increase in the migration of DNA in cells of the exposed organisms. A comparison among DNA lesions per mole number of the test chemical in the exposed groups showed that both BLM and CPT induce more DSBs than CP. Interestingly, Cr(VI) at 20.0 μg/ml was found to induce significantly increased ( p < 0.001) DSBs in the exposed organism as compared to the control. The study while validating neutral Comet assay in D. melanogaster suggests its use for in vivo assessment of environmental chemical induced DSBs.

Simultaneous determination of cyclophosphamide and 4-hydroxycyclophosphamide in human plasma by high-performance liquid chromatography coupled with electrospray ionization tandem mass spectrometry – application to Chinese systemic lupus erythematosus patients

A pharmacogenomics study of cyclophosphamide in systemic lupus erythematosus patients is being conducted in our laboratory in which the plasma concentrations of cyclophosphamide and its active metabolite 4-hydroxycyclophosphamide should be assayed rapidly and sensitively. A rapid, stable and sensitive liquid chromato-graphy/electrospray ionization tandem mass spectrometry method was developed to simultaneously determine cyclophosphamide and 4-hydroxycyclophosphamide in human plasma with ifosfomide as an internal standard. After a protein precipitation with cold acetonitrile and stabilization of 4-hydroxycyclophosphamide by ansyldrazine and extraction with ethyl acetate, separation was performed on a C18 3.5 μm 2.1 × 50 mm column with mobile phase of acetonitrile and water (50:50, v/v) with 0.1% formic acid at 200 μL/min. The chromatographic run time was 3 min. The linear calibration curves ranged from 5 to 5000 ng/mL for cyclophosphamide and 5-500 ng/mL for 4-hydroxycyclophosphamide. The recoveries of the liquid extraction were 54.5%-58.5% for cyclophosphamide and 103.5%-105.5% for 4-hydroxycyclophosphamide. The lower limit of quantification was 5 ng/mL for both analytes. The intra- and inter-day precision was <15% for quality control samples at 4000, 500, 50 ng/mL for cyclophosphamide and 4-hydroxycyclophosphamide at 400, 100, 20 ng/mL. The method was applied in this pharmacogenomics study in Chinese systemic lupus erythematosus patients treated with low-dose cyclophosphamide. The method was efficient with shorter running time and lower limit of quantification compared to previous reports and has been successfully applied in this pharmacogenomics study.

Utilization of the solid sorbent media in monitoring of airborne cyclophosphamide concentrations and the implications for occupational hygiene

The main objective of the study was to evaluate the applicability of two solid sorbent media (Anasorb 708 and Strata X), the impinger filled with distilled water and PTFE filters for determination of airborne cyclophosphamide (CP) in the hospital working environment. For this purpose, air contamination of Masaryk Memorial Cancer Institute (Czech Republic) was monitored using the sampling apparatus containing the samplers described above. In addition, the surface contamination was also determined using the wipe sampling technique. During the monitoring, contamination of three different workplaces (storage room, preparation room and outpatient clinic) was studied. Using Strata X solid sorbent tubes, airborne CP was determined in all (n = 5) samples collected at the outpatient clinic over a 5 day monitoring period (concentration range: 0.3-4.3 ng m(-3)). Other samplers (including PTFE filters) did not collect any detectable amount of CP (the limit of detection, LOD ≤ 0.1 ng m(-3)). Negative results detected at filter samples indicate that CP determined at Strata X samples was most probably of gaseous origin. Surface contamination ranged from <2 to 19, <8 to 418 and 133-15,500 pg cm(-2) at the storage room, preparation room and outpatient clinic, respectively. The study showed that evaporation of antineoplastic drugs should not be neglected, albeit the concentrations determined in our study are relatively low. Therefore, proper monitoring of airborne contamination should involve simultaneous sampling of both particle-bonded and gaseous phases. In this way, Strata X sorbent tubes seem to be an effective tool for the sampling of gaseous CP in the indoor air.

Population pharmacokinetics of cyclophosphamide in patients with thalassaemia major undergoing HSCT shows body weight, CYP450, GST and ALDH polymorphisms as covariates explaining inter-individual variation

Abstract Abstract 1182 Poster Board I-204 Cyclophosphamide (Cy) in combination with busulfan is an important component of myeloablative conditioning regimen used prior to hematopoietic stem cell transplantation (HSCT) for both malignant and non-malignant conditions. We have previously reported up to 20 fold inter-individual variation in the pharmacokinetics (PK) of Cy in patients with beta thalassaemia undergoing HSCT [Blood (ASH Annual Meeting Abstracts), Nov 2004; 104: 99]. PK parameters of Cy have been shown to be associated with regimen related toxicity and outcome of transplant. To explain the basis of the inter-individual variation in Cy PK, we have developed a population PK model. We analyzed the PK of Cy in consecutive children with beta thalassaemia major who received HSCT from HLA identical matched sibling donor at the Christian Medical College, Vellore from 2001 till 2004. A total of 900 cyclophosphamide concentration measurements from 55 patients were included and correlated with age, sex, body weight and 10 polymorphisms in enzymes involved in the metabolism or biotransformation of Cy namely GST A1, M1, T1, P1, CYP2B6, CYP2C9, CYP2C19 and ALDH genes. Non-linear mixed effects modeling analysis was performed with Monolix (version 2.4, www.monolix.org ) to investigate the effect of patient covariates on PK, and to estimate the relative magnitude of inter-individual and inter-occasion variability. A two-compartment pharmacokinetic model was used to describe the data. The pharmacokinetic parameters estimated included elimination rate constant and volume (ke (1/hr), V (L or L/kg)), and the inter-compartmental parameters (k12 and k21 (1/hr)). The distribution of the parameters was assumed log-normal. Body weight was the main covariate which explained the largest portion of the IIV (28% and 20% of V and ke IIV, respectively). In addition, the following genotypes showed differences in the pharmacokinetics: GSTP1*B (1.7X higher ke in MUT versus WT or HET; p Disclosures: No relevant conflicts of interest to declare.

Risks to health professionals from hazardous drugs in Japan: A pilot study of environmental and biological monitoring of occupational exposure to cyclophosphamide

In Japan, concerns exist regarding the dangers inherent when handling cytotoxic drugs, particularly drugs such as 5-FU, Thiotepa, Cytarabine, Tegaful, and Sizofiran which are contained in ampoules or vials, since nurses and medical doctors have been preparing these cytotoxic drugs in the open spaces of wards in the absence of appropriate garments and personal protective equipment. In addition, the administration tubes for these dangerous drugs have been exchanged at the patients' bedside, typically in rooms shared by several patients. To gain insight into the severity of the occupational hazards posed by these practices, we conducted a pilot study of environmental and biological monitoring of occupational exposure to cyclophosphamide (CP). At Nagoya University Hospital, Nagoya, Japan, in February 2006, two departments, A and B, were monitored with surface-wipe, and urine samples were analyzed using the Sessink method (exposure control, The Netherlands). Department A had a preparation room with biological safety cabinet (BSC) where the pharmacists prepare cytotoxic drugs. Department B did not have a BSC. Many areas of the treatment rooms were contaminated with CP. CP was detected on tables and telephone stands where cytotoxic drugs were not used as well as tables used to prepare cytotoxic drugs. Significant differences in CP concentrations were detected from the urine of two of the three nurses who cared for the same patients without gloves. The nurses rotated and inherited the patient who had the highest risk of contamination. CP was detected only once from the urine of the medical doctor who prepared CP. He was not wearing any PPE other than gloves. All of the pharmacists wearing PPE were free from contamination of CP. Regardless of the use of BSC, wards were contaminated with CP. The contamination may not occur due to the sealing used in CP containers and administration tubes when discarding them. CP was detected only once in the urine of a medical doctor who prepared CP by warming it. The cause may be inhalation of CP gas from the injector. The contamination of the nurses may be from dermal absorption because absorption continued even after the shift ended and the nurses left the facility. CP was not detected in pharmacists who followed the guidelines for preparation of CP. All of the medical staff should follow the guidelines when they handle CP.

Pilot Study Comparing the Efficacy of Two Cleaning Techniques in Reducing Environmental Contamination with Cyclophosphamide

Compare the efficacy of the cleaning technique usually employed in our healthcare facility to eliminate environmental contamination with cyclophosphamide with that of the Surface Safe commercial kit. This is a three-step evaluative and comparative study involving: (i) the voluntary contamination of the surface of a hood with a pre-established quantity of cyclophosphamide (20,000,000 ng), (ii) the cleaning of the work surface of the hood using a cleaning technique usually employed in our healthcare facility or that of the product Surface Safe, and (iii) the quantification of cyclophosphamide detected on the work surface. The usual cleaning technique involves the use of a mixture of 0.05% chlorhexidine and 70% ethyl alcohol to clean surfaces, whereas the product Surface Safe involves a combined two-step sodium hypochlorite and sodium thiosulfate wash. The median concentrations of cyclophosphamide detected after the use of the usual technique and the product Surface Safe came to 165 ng cm(-2) (40-570) and 65 ng cm(-2) (57-110), respectively. The results obtained showed an average 99.5% efficacy in reducing the quantity of cyclophosphamide (ng) detected on the work surface for each of the two techniques that were evaluated. The study demonstrates that reducing the residual concentration of cyclophosphamide on work surfaces to levels lower than 1 ng cm(-2) remains difficult despite the use of cleaning techniques with a high percentage of efficacy. It stressed the importance of combining two successive cleaning techniques to maximally restrict the residual concentration of hazardous drugs and suggests the use of a combination of sodium hypochlorite and sodium thiosulfate to best reduce environmental contamination levels.

Stability of Cyclophosphamide in Extemporaneous Oral Suspensions

Cyclophosphamide, an alkylating agent, is widely used for the treatment of many adult and pediatric malignancies. The stability of cyclophosphamide in aqueous- and methylcellulose-based oral suspending vehicles is currently unknown. To develop and validate a stability-indicating high-performance liquid chromatography (HPLC) method to measure cyclophosphamide concentrations in simple syrup and Ora-Plus, and assess the 56-day chemical stability and physical appearance of cyclophosphamide in these suspensions at both room temperature (22 degrees C) and 4 degrees C. The intravenous formulation of cyclophosphamide was diluted to 20 mg/mL in NaCl 0.9%, compounded 1:1 with either suspending vehicle, and stored in the dark in 3-mL amber polypropylene oral syringes at 4 degrees C and 22 degrees C. Aliquots from each syringe were obtained on days 0, 3, 7, 14, 21, 28, 35, 42, 49, and 56 and assayed using the validated stability-indicating HPLC-UV method. A C18 analytical column was used to separate cyclophosphamide from the internal standard, ifosfamide, with a mobile phase of 21% acetonitrile in 79% sodium phosphate buffer. The suspension was examined for odor change, visually examined under normal fluorescent light for color change, and examined under a light microscope for evidence of microbial growth. Samples of cyclophosphamide in both simple syrup and Ora-Plus were stable when kept at 4 degrees C for at least 56 days. At room temperature, cyclophosphamide in simple syrup and Ora-Plus had a shelf life of 8 and 3 days, respectively. No changes in color or odor or evidence of microbial growth were observed. Cyclophosphamide can be extemporaneously prepared in simple syrup or Ora-Plus and stored for at least 2 months under refrigeration without significant degradation.

Population Pharmacokinetics of Cyclophosphamide in Patients with Thalassaemia Major Undergoing HSCT Shows Body Weight, CYP450, GST and ALDH Polymorphisms as Covariates Explaining Inter-Individual Variation.

Abstract 1182Poster Board I-204Cyclophosphamide (Cy) in combination with busulfan is an important component of myeloablative conditioning regimen used prior to hematopoietic stem cell transplantation (HSCT) for both malignant and non-malignant conditions. We have previously reported up to 20 fold inter-individual variation in the pharmacokinetics (PK) of Cy in patients with beta thalassaemia undergoing HSCT [Blood (ASH Annual Meeting Abstracts), Nov 2004; 104: 99]. PK parameters of Cy have been shown to be associated with regimen related toxicity and outcome of transplant. To explain the basis of the inter-individual variation in Cy PK, we have developed a population PK model. We analyzed the PK of Cy in consecutive children with beta thalassaemia major who received HSCT from HLA identical matched sibling donor at the Christian Medical College, Vellore from 2001 till 2004. A total of 900 cyclophosphamide concentration measurements from 55 patients were included and correlated with age, sex, body weight and 10 polymorphisms in enzymes involved in the metabolism or biotransformation of Cy namely GST A1, M1, T1, P1, CYP2B6, CYP2C9, CYP2C19 and ALDH genes. Non-linear mixed effects modeling analysis was performed with Monolix (version 2.4, www.monolix.org) to investigate the effect of patient covariates on PK, and to estimate the relative magnitude of inter-individual and inter-occasion variability. A two-compartment pharmacokinetic model was used to describe the data. The pharmacokinetic parameters estimated included elimination rate constant and volume (ke (1/hr), V (L or L/kg)), and the inter-compartmental parameters (k12 and k21 (1/hr)). The distribution of the parameters was assumed log-normal. Body weight was the main covariate which explained the largest portion of the IIV (28% and 20% of V and ke IIV, respectively). In addition, the following genotypes showed differences in the pharmacokinetics: GSTP1*B (1.7X higher ke in MUT versus WT or HET; p<0.05), CYP3A4*1B (2X higher ke in HET versus WT; p<0.05), and ALDH1A1*2 (2X higher ke in HET versus WT; p<0.05). We have developed a population PK model for Cy in thalassaemic children by considering morphological and biological covariates, which explains more than 45% and 22% (V and ke IIV, respectively) of the variation in Cy PK in these patients. This model-based algorithm may be used to design and plan targeted dose therapy in this group of pediatric patients and to predict the risk of toxicity and outcome of HSCT. Disclosures:No relevant conflicts of interest to declare.

Cyclophosphamide removal from water by nanofiltration and reverse osmosis membrane

The rejection of cyclophosphamide (CP) by nanofiltration (NF) and reverse osmosis (RO) membranes from ultrapure (Milli-Q) water and membrane bioreactor (MBR) effluent was investigated. Lyophilization–extraction and detection methods were first developed for CP analysis in different water matrices. Experimental results showed that the RO membrane provided excellent rejection (>90%) under all operating conditions. Conversely, efficiency of CP rejection by NF membrane was poor: in the range of 20–40% from Milli-Q water and around 60% from MBR effluent. Trans-membrane pressure, initial CP concentration and ionic strength of the feed solution had almost no effect on CP retention by NF. On the other hand, the water matrix proved to have a great influence: CP rejection rate by NF was clearly enhanced when MBR effluent was used as the background solution. Membrane fouling and interactions between the CP and water matrix appeared to contribute to the higher rejection of CP.

Effect of aprepitant (AP) on cyclophosphamide (CPA) pharmacokinetics (PK) in early breast cancer patients

588 Background: AP, a moderate inhibitor of CYP3A4, is a selective neurokinin 1 receptor antagonist recommended by the ASCO guidelines for prevention of high and some moderately emetogenic chemotherapy regimens, including doxorubicin and CPA (AC). CPA is converted to the active 4-OH metabolite primarily by CYP2B6 (48–57%) and by CYP3A4 (12–18%). CYP3A4 also converts 10% of CPA to the N-dechloroethyl metabolite (DCE), which is responsible for neurotoxicity and nephrotoxicity. Because AP is utilized concurrently with CPA, this creates the potential for drug-drug interaction between AP and CPA. The objective of this study was to evaluate the effect of AP on the PK of CPA, 4-OH, and DCE in patients receiving AC. Methods: This double-blinded, placebo controlled, two-period, crossover study included breast cancer patients receiving regimens containing CPA 600 mg/m2 IV for at least two sequential cycles. Prior to each CPA cycle, patients were randomized to receive either oral AP (125 mg on d 1 prior to chemotherapy and 80 mg on d 2 and 3) or placebo for 3 d. During both cycles, patients were also pretreated with ondansetron 24 mg PO and dex 12 mg PO on d 1 and dex 8 mg PO once on d 2 and 3. Rescue anti-emetic medications were permitted. Serial plasma samples were obtained from 0 to 24 h after administration of CPA in combination with AP or placebo in each patient. CPA, 4-OH, and DCE plasma concentrations were determined using HPLC. Area under the plasma versus conc time curve (AUC) was calculated using WinNonlin. Results: 17 patients completed 2 cycles and were evaluated for PK. Geometric mean AUC data for CPA in combination with AP and placebo are summarized in the table. Conclusions: Based on geometric mean ratios ± 90% CI, concurrent administration of AP with CPA did not result in any significant changes in the 4-OH metabolite AUC, but did result in increased parent CPA and decreased DCE drug exposure levels. Based on these results, it is unlikely that aprepitant has a clinically significant effect on the efficacy of CPA. [Table: see text] [Table: see text]

Use of a Closed System Device to Reduce Occupational Contamination and Exposure to Antineoplastic Drugs in the Hospital Work Environment

The aim of the preset study was to evaluate the applicability of a closed system device to protect against occupational contamination and exposure to antineoplastic drugs in the work environment of a hospital. We compared the contamination by and exposure to cyclophosphamide (CPA) between a conventional mixing method and a mixing method using a closed system device. Wipe samples in the preparation room, gloves samples and 24-h urine samples of pharmacists preparing antineoplastic drugs were collected. Working surfaces inside the biological safety cabinet (BSC), front side of the air grilles of the BSC, stainless steel trays, working table and floor were wiped. At first, sample collection was done on 5 days over an interval of 2 weeks using the conventional mixing method. After 2 weeks training for using the closed system device, sample collection was done 5 days over an interval of 2 weeks using the closed system device. When pharmacists prepared antineoplastic drugs by the conventional method, CPA was detected from all wipe samples, and the mean and median concentrations of CPA were 1.0 and 0.16 ng cm(-2), respectively (range was from 0.0095 to 27 ng cm(-2)). When pharmacists prepared antineoplastic drugs with a closed system device, CPA was detected from 75% of the wipe samples at mean and median concentrations of 0.18 and 0.0013 ng cm(-2), respectively (the range was from lower than detection limit to 4.4 ng cm(-2)). Using the closed system device significantly reduced the surface contamination of CPA for all wipe sampling points in the preparation room (Mann-Whitney's U-test). The range of CPA of glove samples used in the conventional method and closed system device ranged from lower than detection limit to 3200 ng per glove-pair and from lower than detection limit to 740 ng per glove-pair, respectively. Using the closed system device significantly reduced the gloves contamination of CPA (Mann-Whitney's U-test). The range of urinary CPA of six pharmacists preparing the antineoplastic drugs with the conventional method and closed system device ranged from lower than detection limit to 170 ng day(-1) and from lower than detection limit to 15 ng day(-1), respectively. Using the closed system device significantly reduced the amount of urinary CPA in pharmacists preparing the antineoplastic drugs (Wilcoxon's signed ranks test). We concluded that a closed system device can reduce occupational contamination and exposure to antineoplastic drugs in the hospital work environment.