Viability of selected microorganisms in parenteral preparations for novel systemic anti-cancer therapy

BACKGROUND

Risk factors for aseptic preparation of parenteral medicines encompass the growth-promoting nature of the preparation. Although many aqueous parenteral preparations do not have growth-promoting properties, inadvertently introduced microorganisms may remain viable. Knowledge about the viability of microorganisms in parenteral preparations can add useful information for assigning shelf life to preparations used to treat cancer patients.

AIM

The aim of the study was to assess the viability of four different facultative pathogenic microorganisms in 20 ready-to-administer parenteral preparations aseptically prepared in hospital pharmacies.

METHODS

Samples of 20 different biologics and small molecules for systemic anti-cancer therapy were inoculated either with different bacteria (i.e., Staphylococcus aureus, Pseudomonas aeruginosa, Enterococcus faecium) or with Candida albicans suspension. The resulting test concentrations were 104-105 microorganisms per mL. Aliquots of inoculated test solutions were transferred in duplicate to tryptic soy agar plates at the time points 0, 4, 24, 48, 144 h. The plates were incubated for 24 h (bacterial strains) and 72 h (C. albicans) at 37 °C and colony forming units (CFUs) were counted.

RESULTS

In most test solutions, especially in monoclonal antibody solutions, increased CFU counts of P. aeruginosa and unchanged or increased CFU counts of E. faecium and S. aureus were registered. Pronounced nutritive properties of monoclonal antibodies and filgrastim were not registered. Azacitidine, pixantrone and vinflunine containing test solutions revealed species-specific bacteriostatic and even bactericidal activity. All test solutions, except nivolumab and pixantrone containing solutions, showed constant or increasing CFU counts of C. albicans after incubation.

CONCLUSION

Viability of the selected pathogenic microorganisms was retained in most of the tested biological and small molecule preparations used to treat cancer patients. Therefore, in pharmacy departments strict aseptic conditions should be regarded and the lack of antimicrobial activity should be considered when assigning shelf life to RTA parenteral preparations.

Microbiological stability tests with simulated broth preparations and integrity testing for sterile standard cytotoxic preparations

Objectives

The objectives were to assess the microbiological stability and the physical enclosure integrity of the overwrapping for batch production of standard cytotoxic injectable solutions.

Methods

Broth culture media were used in place of cytotoxic drugs to assess the worst case in term of microbiological contamination risk. Iterative sterility tests on batches were performed for 60 days using rapid microbiological method. Validation of microbiological growth of culture media was assessed by direct inoculation of <100 CFU/mL of six microbiological strains recommended by European Pharmacopeia. Validation of the ability of growth of microorganisms in 11 cytotoxic solutions and one monoclonal antibody was assessed using eight strains. In addition, the physical integrity of the seal of the overwrapping containing cytotoxic preparations was assessed by dynamometric method and dye penetration test.

Results

No microbiological contamination was observed on all units of batches for 60 days of investigation. The ability to detect microbiological growth in cytotoxic solutions was validated for the eight challenge microorganisms after 1/10 dilution for cytotoxic investigated, except for 5 Fluorouracil, gemcitabine and cisplatin. In addition, physical integrity testing of the seal of overwrapping pointed out the need of specific validation of heatsealer and operator education.

Conclusions

Besides physico-chemical testing, microbiological stability testing combined to physical integrity testing is the additional part of the development method for batch production of sterile drugs in hospital.

Removal of bacterial growth inhibition of anticancer drugs by using complexation materials

In the context of batch production of cytotoxic drugs in hospital pharmacies with the need of sterility testing, the objective was to validate the use of Rapid Microbiological Method (RMM), and to develop adequate neutralization method in case of inhibition of bacterial growth. The potential microbiological growth inhibitory effect of three anticancer drugs (5 fluorouracil, irinotecan and oxaliplatin) selected for batch production was assessed on BacT/ALERT® system. Among cytotoxic drugs, only 5FU exhibited inhibitory effect on microbiological growth using rapid microbiological method. To counteract this effect our purpose was to use neutralizing agents complexing the drug i. e. activated carbon or ion exchange resins. The microbiological bactericidal concentration of 5FU was very low (1.10–4 mg/mL) indicating the absolute need to neutralize the whole drug before sterility test. The complexation was validated by High Performance Liquid Chromatography control of the residual 5FU concentration in solution after the use of neutralizing agents. Only activated carbon was able to fully capture 5FU when previously diluted at 5 mg/mL. Conversely, the resins, in the condition of the study, were not able to fully capture 5FU whatever the dilution. The microbiological growth on BacT/ALERT® system after active carbon treatment was successfully confirmed with Staphylococcus aureus. Based on this validation results a method was then developed to routinely be able to perform sterility test of the batches produced and was confirmed on five microbiological species (i. e. S. aureus, Pseudomonas aeruginosa, Bacillus subtilis, Candida albicans, Aspergillus brasiliensis). Our work gives a new insight for considering sterility testing by rapid microbiological method even for drugs exhibiting inhibitory effect on microbiological growth.

Implementation and microbiological stability of dose-banded ganciclovir infusion bags prepared in series by a robotic system

OBJECTIVES

The implementation of dose-banding (DB) in centralised, pharmacy-based cytotoxic drug preparation units allows the preparation of standardised doses in series. The aim of this study was to evaluate the feasibility of DB for the prescribing of ganciclovir (GV) infusion solutions and to investigate the microbiological stability of dose-banded, automatically prepared ready-to-administer GV infusion bags by media-fill simulation tests and sterility tests.

METHODS

The frequency of prescription of GV doses was retrospectively analysed before and after implementing the DB scheme. Four dose-ranges or 'bands' and the corresponding standard doses (250, 300, 350, 400 mg) were identified. The maximum variance was set at ±10% of the individually prescribed dose. The aseptic preparation of a series of GV infusion bags was simulated with double strength tryptic soy broth as growth medium and prefilled 0.9% NaCl polyolefin infusion bags as primary packaging materials. The simulation process was performed with the APOTECAchemo robot on five consecutive days. In total, 50 infusion bags were filled, incubated and stored for 12 weeks at room temperature. The media-filled bags were visually inspected for turbidity after 2, 4, 8, 10 and 12 weeks. Following incubation, growth promotion tests were performed. During the simulation tests, airborne contamination was monitored with settle plates and microbial surface contamination with contact plates. Pooled sterility tests were performed for a series of 10 standard GV infusion bags after a 12-week storage period under refrigeration (2 °C-8 °C).

RESULTS

After implementation of the DB scheme, about 60% of the prescribed GV doses were prepared as standard preparations by the robotic system. The number of different GV doses was reduced by 61.8% (76 vs 29). None of the 50 media-filled bags showed turbidity after a storage period of 12 weeks, indicating the absence of microorganisms. The environmental monitoring with settle/contact plates matched the recommended limits set for cleanroom Grade A zones, except in the loading area of the robot. Media fills used for the sterility tests remained clear during the incubation period, thereby revealing sterility. Positive growth promotion tests proved the process's reliability.

CONCLUSIONS

A DB scheme for prescribing and preparation of standard GV infusion bags was successfully implemented. Microbiological tests of aseptic preparation of infusion bags in series by the APOTECAchemo robot revealed an adequate level of sterility and a well-controlled aseptic procedure. The sterility was maintained over extended storage periods, thereby encouraging extended beyond-use dating.

Microbial growth tests in anti-neoplastic injectable solutions

The Institut Gustave-Roussy (IGR) Department of Clinical Pharmacy (DCP) ensures the annual preparation of about 30 000 therapeutic batches of anti-neoplastic agents.High performance thin-layer chromatography (HPTLC) allows postproduction quality control of these batches.Although the centralized chemotherapy manufacturing unit has been recently ISO 9001:2000 certified, it was considered to improve the quality level of manufactured batches even further.The viability of micro-organisms (bacteria and fungi) in appropriate sterile media containing various anti-neoplastic agents at therapeutic concentration was assessed to demonstrate the lack of contamination during our manufacturing process in the isolator.After 14 days of incubation in these media, the results show the absence of contamination of the manufactured batches.This leads us to conclude that using sterile drugs and sterile medical devices in a sterile isolator allows the manufacture of sterile therapeutic batches with excellent confidence.

Stability of topotecan infusion solutions in polyvinylchloride bags and elastomeric portable infusion devices

Purpose. The purpose of this study was to determine the physicochemical stability of topotecan after reconstitution and after further dilution in two commonly used infusion fluids (0.9% sodium chloride, 5% dextrose) in both polyvinylchloride (PVC) bags and elastomeric portable infusion devices.

Methods. Each vial of topotecan (Hycamtin®) was reconstituted with sterile water for injection, yielding a nominal concentration of 1 mg/mL. Topotecan infusion solutions were aseptically prepared by further dilution of reconstituted topotecan solutions with either 0.9% sodium chloride or 5% dextrose in both PVC bags and portable elastomeric infusion devices, in amounts yielding topotecan concentrations of 10 µg/mL, 25 µg/mL, or 50 µg/mL. Test solutions were stored light-protected at room temperature (25°C) or under refrigeration (2-8°C) in parallel. One test solution of the nominal concentration of 10 µg/mL topotecan in a 0.9% sodium chloride PVC infusion bag was stored under ambient light conditions (mixed daylight and normal laboratory fluorescent light) at room temperature. Topotecan concentrations were obtained periodically throughout a 4-week storage period via a stability-indicating high performance liquid chromatography assay with ultra-violet detection. In addition, measurements of pH values were performed regularly, and test solutions were visually examined for colour change and precipitation.

Results. The stability tests revealed that the currently available topotecan formulation is stable (at a level of ≥90% topotecan) after reconstitution and dilution, independent of temperature (refrigerated, room temperature), the vehicle (0.9% sodium chlo-ride, 5% dextrose), the concentration (10 µg/mL, 25 µg/mL, or 50 µg/mL), or the container material (PVC bags, elastomeric portable infusion devices). The results were obtained over a test period of ≥4 weeks. Topotecan infusion solutions exposed to daylight were stable for only 17 days.

Conclusions. Reconstituted and diluted topotecan infusion solutions are shown to be physicochemically stable for 4 weeks. Light protection during administration is not necessary.

Dose-banding of carboplatin: rationale and proposed banding scheme

Background. In dose-banding (DB) prescribed doses of cancer chemotherapy are fitted to doseranges or ‘bands’ and standard doses for each band are provided using a selection of pre-filled infusions or syringes, either singly or in combination. DB is used for several drugs where dose is based on body surface area. No DB-scheme has been reported for carboplatin, which, in clinical practice, is routinely dosed according to renal function.

Study objective. To assess the rationale for DB of carboplatin with regards to factors that influence dosing accuracy, develop a DB scheme, and discuss its potential use and limitations.

Methods. Prospective evaluations of carboplatin area under the plasma concentration – time curve (AUC) following application of the Calvert-formula were identified by a literature search. A relevant carboplatin dose range for construction of a DB-scheme with Calvert-formula based doses was obtained from published glomerular filtration rate distributions for patients receiving carboplatin.

Results. A DB-scheme was developed for individually calculated carboplatin doses of 358–1232 mg, with 35 mg increments between each standard dose and a maximum deviation of 4.7% from prescribed dose. The proposed DB-scheme covers the GFR-ranges 47–221 mL/min and 26–151 mL/min for patients receiving doses based on the target AUCs of 5 and 7 mg/mL/min, respectively.

Conclusion. There is a strong scientific rationale to support DB of carboplatin. The proposed banding scheme could introduce benefits to patients and healthcare staff but, as with other DB schemes, should be validated with prospective clinical and pharmacokinetic studies to confirm safety and efficacy.

Viability of microorganisms in bags of cytotoxic drugs

Objectives. The aim of this report was to study the viability of five microorganisms (Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, S epidermidis and Candida albicans) in chemotherapeutic solutions made up 1-2 days before administration.

Methods. The four preparations studied were 0.5 mg/mL cisplatin, 1.8 mg/mL doxorubicin, 5 mg/mL 5-fluorouracil, and 5 mg/mL cyclophosphamide. All four solutions were tested at a temperature of 258C, and doxorubicin and cyclophosphamide were also tested at 48C. The concentrations of the microorganisms in the preparations were determined 2, 24, 48, 72, and 96 hours after inoculation.

Results. No microbial growth was found; on the contrary, bacterial and fungal growth decreased rapidly and substantially with cisplatin and doxorubicin (by 2log after 24 hours), moderately with 5-fluorouracil, and weakly or not at all with cyclophosphamide. Refrigeration at 48C appeared to slow the decreased growth of the microorganisms when compared with storage at 258C.

Conclusion. As no bacterial or fungal growth was seen in the four solutions of cytotoxic agents tested, the practice of preparing such solutions under a hood with vertical laminar ventilation according to good practice in the preparation of sterile solutions 1 or 2 days before administration to patients is validated. J Oncol Pharm Practice (2001) 6, 167-171.

Viability of Selected Microorganisms in Non-Cytotoxic Aseptic Preparations

: Numerous ready-to-use parenteral solutions are aseptically prepared in pharmacy-based aseptic preparation units. Microbiological stability of the preparations is influenced by the cleanroom environment, the complexity of the aseptic process, conditions during administration and the microbiological vulnerability of the products.

: The aim of the study was to evaluate the ability of four different pathogens related to hospital infections to grow in ready-to-use, non-cytotoxic parenteral products aseptically prepared in hospital pharmacies.

: In four consecutive series the antimicrobial activity of the following products was tested: caspofungin 35 mg or 70 mg in 250 mL 0.9 % NaCl solution (NS), micafungin 0.5 mg/mL in NS, vancomycin 5 mg/mL in G5/G10, heparin-sodium 1 IE/mL in NS, epinephrine 0.02 mg/mL in G5, norepinephrine 0.01 mg/mL in G5, phenylephrine 0.1 mg/mL, KCl solution 0.8 mmol/mL, trace elements 1:1 in G5/G10, midazolam 1 mg/mL injection solution, tranexamic acid 100 mg/mL injection solution, 50 % glucose solution, SMOFlipid 20 % lipid emulsion, 1 % propofol injection.

Nine milliliter aliquots of each test solution were inoculated with 1 mL suspension of selected strains, i. e.

: Most of the tested preparations induced no growth inhibition of the tested organisms. The selected strains lost viability in preparations containing vancomycin, phenylephrine or midazolam after a period of a few hours or days. Glucose 50 % w/v solution generated antimicrobial activity against

: The lack of antimicrobial properties of ready-to-use, non-cytotoxic solutions should be considered while determining the shelf-life of the products. Ready-to-use preparations should be kept refrigerated whenever possible to inhibit the multiplication of any contaminating organism.

Stability of Reconstituted and Diluted Mitomycin C Solutions in Polypropylene Syringes and Glass Vials

: Mitomycin C (MMC) is widely used in treatment of non-muscle invasive bladder cancer at a 1 mg/mL concentration, by intravesical instillation. MMC is also used as an ophthalmic procedure in glaucoma care mostly with 0.2 mg/mL concentration. To accelerate syringes provision, it could be interesting to demonstrate the stability of the drug, in order to be able to prepare the chemotherapeutic drug several hours before the chemotherapy administration.

: A stability indicating HPLC-UV method was developed and validated according to the ICH guidelines. Concentrations of the MMC stored at 25 °C and 60 % of relative humidity and protected from light in polypropylene syringes (1 mg/mL and 0.2 mg/mL) or glass vials (1 mg/mL) were evaluated for 96 h and compared to the initial observed concentrations.

: MMC stability was demonstrated in syringes and glass vials at 1 mg/mL only for 8 h in water for injections and for 10 h at 0.2 mg/mL in 0.9 % sodium chloride solutions, because relative concentrations (95 % confidence interval of the mean of 3 samples) were systematically over 90 % of the initial concentrations. After 96 h the relative concentrations were found below 80 % as compared to initial concentrations, thus indicating instability of these solutions. Degradation products were observed and remained below 3 %.

: This study confirms that MMC solutions for ophthalmic application at 0.2 mg/mL or vesical instillation at 1 mg/mL have to be formulated extemporaneously to maintain the desired concentration.

A national survey investigating UK prescribers' opinions on chemotherapy dosing and 'dose-banding'

AIMS

The primary purpose of dose-banding for cancer chemotherapy is to reduce patient waiting times, but dose-banding also has additional benefits, such as reduced drug wastage, reduced stress for staff, and prospective quality control of infusions. However, the uptake of dose-banding seems fairly low. Possible reasons for this are a reluctance to use dose-banding for clinical reasons or a lack of awareness. Despite the seemingly minor change from established practice of dose preparation, dose-banding has the potential to alter patient chemotherapy exposure. The aim of this study was to investigate prescribers' awareness of dose-banding and their opinions on the scope and limitations of dose-banding in the context of UK chemotherapy services.

MATERIALS AND METHODS

This survey was performed throughout the UK by use of a postal questionnaire, which was validated before national distribution to 1104 oncologists and haematologists. The questionnaire contained both quantitative and qualitative elements. A database was created for data entry and analysis.

RESULTS

The response from prescribers was encouraging for a postal questionnaire, with a 35% response rate (387 responses). Many were aware of the concept of dose-banding (>80%) and were also supportive of the system. The weakness around body surface area-based dosing was a commonly discussed topic. However, opinions on which is the maximum acceptable deviation from the prescribed dose with dose-banding were controversial, and there was a concern about the lack of evidence to support the use of dose-banding. The views on whether carboplatin and targeted therapies should be dose-banded were also divided.

CONCLUSIONS

There was general support for dose-banding, but concerns about the lack of an evidence base could be a barrier to the wider introduction of the system. Consequently, more clinical studies are required to justify the safety and efficacy of dose-banding, and also to evaluate whether dose-banding is acceptable within clinical trials.

Impact of combinations of antineoplastic drugs on intestinal microflora in 9 patients with leukaemia

The impact of antineoplastic drugs on the intestinal microflora was studied in 9 patients with acute leukaemia during chemotherapy and in 5 patients also during chemotherapy-induced neutropenia. Quantitative and qualitative microbiological analyses of faecal samples obtained before and during chemotherapy showed significantly increased counts of Bacteroides spp. in 3/9 patients and, during neutropenia, significantly increased counts of yeasts in 2/5 patients; however, the intestinal microflora was stable in most patients.