Complex I inhibitor of oxidative phosphorylation in advanced solid tumors and acute myeloid leukemia: phase I trials

Although targeting oxidative phosphorylation (OXPHOS) is a rational anticancer strategy, clinical benefit with OXPHOS inhibitors has yet to be achieved. Here we advanced IACS-010759, a highly potent and selective small-molecule complex I inhibitor, into two dose-escalation phase I trials in patients with relapsed/refractory acute myeloid leukemia (NCT02882321, n = 17) and advanced solid tumors (NCT03291938, n = 23). The primary endpoints were safety, tolerability, maximum tolerated dose and recommended phase 2 dose (RP2D) of IACS-010759. The PK, PD, and preliminary antitumor activities of IACS-010759 in patients were also evaluated as secondary endpoints in both clinical trials. IACS-010759 had a narrow therapeutic index with emergent dose-limiting toxicities, including elevated blood lactate and neurotoxicity, which obstructed efforts to maintain target exposure. Consequently no RP2D was established, only modest target inhibition and limited antitumor activity were observed at tolerated doses, and both trials were discontinued. Reverse translational studies in mice demonstrated that IACS-010759 induced behavioral and physiological changes indicative of peripheral neuropathy, which were minimized with the coadministration of a histone deacetylase 6 inhibitor. Additional studies are needed to elucidate the association between OXPHOS inhibition and neurotoxicity, and caution is warranted in the continued development of complex I inhibitors as antitumor agents.

[Research progress in ecological prevention of dental caries]

Dental caries is one of the most common oral diseases around the world. Dental plaque attached to the surfaces of teeth is the main biological factor leading to caries. Although fluoride is still one of the most commonly used methods to prevent caries, with the change of epidemiological characteristics of caries and the update of the understanding of caries etiology, it is necessary to use other ecological methods such as antimicrobial peptides, arginine, probiotics and natural products, etc. to enhance the effect of fluoride in preventing dental caries. The present article reviews the research progress on the ecological approaches for caries prevention in recent years.

[The imaging characteristics and prognosis of patients with cochlear implants whose cochlear nerves are not shown on MRI]

Objective: To analyze the temporal bone CT and inner ear magnetic resonance imaging characteristics of cochlear implant patients with no cochlear nerve display in the inner auditory canal under MRI. To retrospectively analyze the long-term hearing and speech rehabilitation effects of such patients after cochlear implant. And to analyze the correlation between the results of imaging examinations and the postoperative effects of cochlear implant patients with this type of cochlear nerve deficiency. Methods: A total of 88 children with cochlear nerve deficiency, who underwent cochlear implantation in Shandong Provincial ENT Hospital from May 2014 to October 2018, were enrolled. Patients with cochlear malformations were excluded,only the patients with cochlear nerve deficiency whose cochlear structure was normal and no cochlear nerve displayed in inner auditory canal under MRI were enrolled. There were 64 patients, including 4 bilaterally implanted, 68 ears in total, with an average age of (2.8±1.7) years (range 1-6 years) at the time of implantation. The implanted product was Cochlear, including 24RECA and 512 models. All patients underwent inner ear magnetic resonance imaging and temporal bone CT scan before operation. Auditory speech function assessments were performed at 12 months, 24 months, and 36 months after surgery, including categories of auditory performance (CAP), speech intelligibility rating (SIR) and hearing aid threshold test. The imaging evaluation content included the width of the cochlear nerve canal of temporal bone CT, the width of the internal auditory canal, the width of the auditory nerve at the cerebellopontine angle of the inner ear MRI, and the ratio of the facial nerve to the width of the auditory nerve at the cerebellopontine angle. The correlations between the results of postoperative hearing aid hearing threshold, CAP, SIR and imaging results were analyzed. Results: Among the 64 cases of cochlear nerve not shown under MRI, 56 ears with CT data showed that the width of the cochlear nerve canal in temporal bone CT was (0.72±0.30) mm (mean±standard deviation, the same below), and the width of the internal auditory canal was (4.07±1.10) mm; 66 ears with MRI data showed that the diameter of the auditory nerve at the cerebellopontine angle of the inner ear MRI was (1.58±0.27) mm, the diameter of the facial nerve was (1.57±0.27) mm, and the ratio of the diameter of the facial nerve to the auditory nerve was (1.02±0.23). The average hearing thresholds at 12, 24, and 36 months after surgery were (46.8±2.5) dB HL, (40.7±0.8) dB HL, and (36.8±1.5) dB HL, respectively. The preoperative and postoperative CAP scores at 12, 24 and 36 months were (1.0±1.0), (3.8±1.4), (4.5±1.4) and (5.1±0.7) points, respectively. The preoperative and postoperative SIR scores at 12, 24, and 36 months were (1.1±0.3), (1.9±0.9), (2.5±0.9), and (2.9±0.6) points, respectively. The hearing threshold at 24 months after surgery was negatively correlated with the width of the internal auditory canal of temporal bone CT (r=-0.349, P=0.037), and the hearing threshold at 36 months after surgery was positively correlated with the ratio of the diameter of the facial nerve to the auditory nerve at the cerebellopontine angle of the inner ear MRI (r=0.740, P=0.001). Conclusions: Children with cochlear implants whose cochlear nerves are not shown on MRI can benefit from cochlear implantation, and their speech and auditory functions can improve significantly after surgery. The width of the internal auditory canal in the temporal bone CT and the ratio of the diameter of the facial nerve to the auditory nerve at the cerebellopontine angle of the inner ear MRI may be related to the long-term hearing threshold after surgery.

Physician deaths from corona virus (COVID-19) disease

Background

The COVID-19 pandemic has caused much morbidity and mortality to patients but also health care providers.

Aims

We tabulated the cases of physician deaths from COVID-19 associated with front-line work in hopes of mitigating future events.

Methods

On 15 April 2020, a Google internet search was performed using the keywords ‘doctor’, ‘physician’, ‘death’, ‘COVID’ and ‘coronavirus’ in English and Farsi, and Chinese using the Baidu search engine. The age, sex and medical speciality of physicians who died from COVID-19 in the line of duty were recorded. Individuals greater than 90 years of age were excluded.

Results

We found 278 physicians who died with COVID-19 infection, but complete details were missing for 108 individuals. The average age of the physicians was 63.7 years with a median age of 66 years, and 90% were male (235/261). General practitioners and emergency room doctors (108/254), respirologists (5/254), internal medicine specialists (13/254) and anaesthesiologists (6/254) comprised 52% of those dying. Two per cent of the deceased were epidemiologists (5/254), 2% were infectious disease specialists (4/254), 6% were dentists (16/254), 4% were ENT (9/254) and 3% were ophthalmologists (8/254). The countries with the most reported physician deaths were Italy (121/278; 44%), Iran (43/278; 15%), Philippines (21/278; 8%), Indonesia (17/278; 6%), China (16/278; 6%), Spain (12/278; 4%), USA (12/278; 4%) and UK (11/278;4%).

Conclusions

Physicians from all specialities may die from COVID. Lack of personal protective equipment was cited as a common cause of death. Consideration should be made to exclude older physicians from front-line work.

Stability of Ciprofloxacin and Vancomycin Hydrochloride in AutoDose Infusion System Bags

The objective of this study was to evaluate the physical and chemical stability of ciprofloxacin 400 mg/100 mL and vancomycin as the hydrochloride 1 g/100 mL each admixed in 0.9% sodium chloride injection packaged in AutoDose Infusion System bags.

Triplicate test samples were prepared by admixing the necessary amount of each antibiotic with a portion of 0.9% sodium chloride injection and bringing the admixture of each drug to a final volume of 100 mL with additional 0.9% sodium chloride injection. The test solutions were packaged in ethylene vinyl acetate (EVA) plastic containers (AutoDose dags) designed for use in the AutoDose Infusion System. Samples were protected from light and evaluated at appropriate intervals for up to 7 days at 23°C and up to 30 days at 4°C.

Physical stability was assessed using a multistep evaluation procedure that included turbidimetric and particulate measurement as well as visual inspection. Chemical stability was assessed using stability-indicating HPLC analytical techniques based on the determination of drug concentrations initially and at appropriate intervals over the study periods. The admixtures were clear and colorless when viewed in normal fluorescent room light and with a Tyndall beam. Measured turbidity and particulate content were low and exhibited little change. HPLC analysis found that both ciprofloxacin and vancomycin hydrochloride remained stable for 30 days at 4°C and 7 days at 23°C.

Both ciprofloxacin and vancomycin hydrochloride exhibited physical and chemical stability consistent with previous studies on these drugs. The AutoDose Infusion System bags were not found to affect adversely the physical and chemical stability of these antibiotics.

Incompatibility of Erythromycin Lactobionate and Sulfamethoxazole/Trimethoprim with Linezolid Injection

The objective of this study was to evaluate the physical compatibility and chemical stability of linezolid 200 mg/100 mL admixed with erythromycin lactobionate 500 mg and separately with sulfamethoxazole 400 mg/trimethoprim 80 mg for up to 7 days at 4° C and 23° C. The test samples were prepared by adding the required amount of erythromycin lactobionate and sulfamethoxazole/trimethoprim to separate bags of linezolid injection. Evaluations were made at the initial time point and at 1, 3, 5, and 7 days of storage at temperatures of 4° C and 23° C for physical and chemical stability. Physical stability was assessed using visual observation in normal light and a high-intensity monodirectional light beam (Tyndall beam). In addition, turbidity and particle content were measured electronically. Chemical stability was evaluated by using stability-indicating high-performance liquid chromatographic (HPLC) analytical techniques. The linezolid admixtures with erythromycin lactobionate were clear and colorless when viewed in normal fluorescent room light and using a Tyndall beam. Measured turbidity and particulate content were low and exhibited little change. HPLC analysis found no loss of linezolid in any sample stored at either temperature throughout the study. However, erythromycin lactobionate underwent rapid and extensive losses. Under refrigeration, erythromycin losses were about 45% in 24 hours; at room temperature, losses of over 80% occurred during the first day. The linezolid admixtures with sulfamethoxazole/trimethoprim resulted in gross precipitation nearly immediately upon preparation of all samples. The precipitate consisted of white needle-like crystals. HPLC analysis found that both sulfamethoxazole and trimethoprim had precipitated. Consequently, no further analysis was performed on these samples.

Stability of busulfan injection admixtures in 5 % dextrose injection and 0.9% sodium chloride injection

Objective. The purpose of this study was to deter mine the stability of busulfan injection at 0.5 and 0.1 mg/mL admixed in 5% dextrose injection and 0.9% sodium chloride injection in PVC and polyolefm bags over 24 hours at 23°C.

Methods. The busulfan injection was prepared by dissolving the bulk powder in a 1:2 mixture of N,N-dimethylacetamide and polyethylene glycol 400 to form a 6 mg/mL solution. The injection was filtered and admixed in the infusion solutions to yield busulfan concentrations of 0.5 and 0.1 mg/mL. Evaluations were performed initially and after 4, 8, and 24 hours of storage for physical and chemical stability. The admix tures were evaluated for physical stability using visual observation in normal light and using a high-intensity monodirectional light beam as well as measuring turbidity. The chemical stability was evaluated by using a stability-indicating HPLC analytical technique.

Results. No physical instabilities were observed. However, busulfan is chemically unstable. At 0.5 mg/mL, potency of at least 95% was retained through 4 hours and at least 90% was retained through 8 hours. After 24 hours, losses of 20% to 30% occurred. At 0.1 mg/mL, drug loss was more rapid. Potency of at least 90% was retained through 4 hours. Losses after 24 hours were about 30% to 40%.

Conclusions. Busulfan injection admixed in 5% dextrose injection or 0.9% sodium chloride injection is unstable. At a concentration of 0.5 mg/mL, ade quate drug delivery is provided within 8 hours of admixture. At the lower concentration of 0.1 mg/mL, adequate drug delivery is only provided for 4 hours.

Fusion protein encoded by a CTLA-4 targeted DNA construct binds to human dendritic cells

Fusing antigens to cytotoxic T-lymphocyte antigen 4 (CTLA-4) represents an effective approach to enhance DNA vaccine efficacy. It has been speculated that the direct targeting of CTLA-4 fusion antigens to antigen-presenting cells (APCs) causes antigens to be processed and presented to T cells more efficiently, leading to a stronger immune response. In the present study, dendritic cells (DCs), the most potent APCs, were generated from human monocytes. The specific binding of CTLA-4 fusion protein to DCs was investigated by flow cytometry. The results showed that the CTLA-4 fusion protein was capable of binding to the B7 molecules on human DCs with specificity.

Mucosal and systemic immunization with targeted fusion anti-caries DNA plasmid in young rats

Early life vaccination is necessary to protect young children from dental caries. Our group had previously reported that a plasmid DNA vaccine pGJA-P/VAX against the glucosyltransferase (GTF) enzyme and cell surface antigen AgI/II (PAc) of Streptococcus mutans (S. mutans) elicited a specific and protective immunity in adult experimental animal models. In this report, early life immunization with the same plasmid was studied following intranasal (i.n.) and intramuscular (i.m.) delivery in murine models. The potential of inducing mucosal and systemic immune responses to special antigens was measured by ELISA. In addition, cytokine production and protection effectiveness against dental caries formation were also investigated. In the i.n. route, rats were primed when they were 5 days old, and boosted after 10 and 20 days with either plasmid pGJA-P/VAX-bupivacaine complexes, or pGJA-P/VAX alone, or empty vector. The pGJA-P/VAX-bupivacaine combination was able to mount the immune responses characterized by increased antibody levels of specific salivary IgA and serum IgG, preferential IFN-gamma production and significant reduction in the dental caries lesions. In the i.m. route, rats were vaccinated with either pGJA-P/VAX alone or empty vector with the same immunization schedule as the i.n. route. Plasmid pGJA-P/VAX alone induced a significant increase in the serum IgG and IFN-gamma production. However, it was not effective in eliciting specific salivary IgA and in decreasing the dental caries formation. All these findings indicate the feasibility of immunity with a targeted fusion DNA vaccine to a young immune system.

Immunogenicity and persistence of a targeted anti-caries DNA vaccine

We have previously reported that a targeted anti-caries DNA vaccine, pGJA-P, induced accelerated and increased antibody responses compared with a non-targeted anti-caries DNA vaccine. Recently, pGJA-P/VAX, a new targeted anti-caries DNA vaccine for human trials, was constructed by replacing the pCI vector used in the construction of pGJA-P with pVAX1, the only vector authorized by the US Food and Drug Administration in clinical trials. Here, we report on our exploration of the kinetics of the antibody responses generated following pGJA-P/VAX immunization and the persistence of pGJA-P/VAX at both the inoculation site and the draining lymph nodes. Intranasal vaccination of mice with pGJA-P/VAX induced strong antibody responses that lasted for more than 6 months. Furthermore, pGJA-P/VAX could still be detected at both the inoculation site and the draining cervical lymph nodes 6 months after immunization. Thus, the persistent immune responses are likely due to the DNA depot in the host, which acts as a booster immunization.

Drug compatibility with new polyolefin infusion solution containers

PURPOSE

The compatibility of new polyolefin (VISIV) containers with seven drugs that have exhibited sorption to polyvinyl chloride (PVC) containers and sets and an additional four drugs that have exhibited leaching of plasticizer or other polymer matrix components from PVC containers and sets was studied.

METHODS

For the sorption portion of the study, amiodarone hydrochloride, carmustine, regular human insulin, lorazepam, nitroglycerin, sufentanil citrate, and thiopental sodium and their respective reference standards were used. For the leaching portion of the study, docetaxel, paclitaxel, tacrolimus, teniposide, and diethylhexyl phthalate (DEHP) reference standard, were used. A 350-mL quantity of each test admixture was prepared, and 100-mL aliquots were transferred into three of the VISIV containers. The containers were stored at ambient temperature and exposed to fluorescent light. Samples for analysis were taken initially and after 24 hours for all drugs except carmustine, which was evaluated for only 6 hours because of its limited stability. High-performance liquid chromatography was used to evaluate each test solution.

RESULTS

Of the seven drugs subject to sorption to PVC, only insulin showed a substantial loss in the VISIV containers. Carmustine exhibited a loss consistent with the drug's known chemical stability. None of the drugs that are known to leach plastic components, such as DEHP plasticizer, from PVC equipment exhibited any leached components in the VISIV containers.

CONCLUSION

Of the drugs tested, only insulin exhibited sorption to the new VISIV polyolefin containers. No leaching of plastic components, such as plasticizer, from the containers was found with any of the surfactant-containing drugs.

Protective efficacy of a targeted anti-caries DNA plasmid against cariogenic bacteria infections

We have previously reported that a targeted anti-caries DNA plasmid pGJA-P/VAX which was constructed against the antigenic determinants of Streptococcus mutans (S. mutans) successfully induced antibody responses in mice and monkeys. The present study explored the protective efficacy of pGJA-P/VAX against cariogenic bacterial challenge. Groups of rats were orally challenged with S. mutans or Streptococcus sobrinus (S. sobrinus) and then immunized with pGJA-P/VAX or the vector pVAX1 intranasally. Serum IgG and salivary IgA antibody levels were assessed by an enzyme-linked immunosorbent assay and caries activity was evaluated by the Keyes method. The results showed that specific salivary IgA antibody responses were induced following intranasal vaccination with pGJA-P/VAX. Moreover, immunization with pGJA-P/VAX resulted in significantly reduced enamel and dentinal caries lesions in rats after S. mutans infection and significantly reduced enamel caries lesions after S. sobrinus infection. Thus, pGJA-P/VAX was not only protective toward S. mutans infection, but also provided cross-strain protection against S. sobrinus infection in rats.

Physical and chemical stability of palonosetron hydrochloride with dacarbazine and with methylprednisolone sodium succinate during simulated y-site administration

The objective of this study was to evaluate the physical and chemical stability of mixtures of undiluted palonosetron hydrochloride 50 micrograms/mL with dacarbazine 4 mg/mL and with methylprednisolone sodium succinate 5 mg/mL in 5% dextrose injection during simulated Y-site administration. Triplicate test samples were prepared by admixing 7.5 mL of palonosetron hydrochloride with 7.5 mL of dacarbazine solution and, separately, methylprednisolone sodium succinate solution. Physical stability was assessed by using a multistep evaluation procedure that included both turbidimetric and particulate measurement as well as visual inspection. Chemical stability was assessed by using stability-indicating high-performance liquid chromatographic analytical techniques that determined drug concentrations. Evaluations were performed immediately after mixing and 1 and 4 hours after mixing. The palonosetron hydrochloride-dacarbazine samples were clear and colorless when viewed in normal fluorescent room light and when viewed with a Tyndall beam. Measured turbidities remained unchanged; particulate contents were low and exhibited little change. High-performance liquid chromatography analysis revealed that palonosetron hydrochloride and dacarbazine remained stable throughout the 4-hour test with no drug loss. Palonosetron hydrochloride is, therefore, physically compatible and chemically stable with dacarbazine during Y-site administration. Within 4 hours, the mixtures of palonosetron hydrochloride and methylprednisolone sodium succinate developed a microprecipitate that became a white precipitate visible to the unaided eye. The precipitate was analyzed and identified as methylprednisolone. Palonosetron hydrochloride is incompatible with methylprednisolone sodium succinate.

Compatibility of palonosetron with cyclophosphamide and with ifosfamide during simulated Y-site administration

PURPOSE

The physical and chemical compatibility of palonosetron with cyclophosphamide and with ifosfamide during simulated Y-site administration was studied.

METHODS

Test samples were prepared in triplicate by mixing 7.5 mL of palonosetron hydrochloride 50 microg (of palonosetron) per milliliter with 7.5 mL of cyclophosphamide 10 mg/mL and with ifosfamide 20 mg/mL. Physical stability was assessed by turbidimetry, particle sizing, and visual inspection. Chemical stability was assessed by stability-indicating high-performance liquid chromatography. Evaluations were performed immediately and one and four hours after mixing.

RESULTS

The samples were clear and colorless when viewed in normal fluorescent room light and when viewed with a high-intensity monodirectional light. Turbidity remained unchanged, and particulate content was low and exhibited little change. Palonosetron, cyclophosphamide, and ifosfamide remained chemically stable throughout the four-hour test period.

CONCLUSION

Palonosetron hydrochloride was physically compatible with cyclophosphamide or ifosfamide during simulated Y-site administration.

Physical and chemical stability of palonosetron hydrochloride with Lorazepam and midazolam hydrochloride during simulated y-site administration

The objective of this study was to evaluate the physical and chemical stability of undiluted palonosetron hydrochloride 50 micrograms/mL in combination with lorazepam 0.5 mg/mL or midazolam hydrochloride 2 mg/mL in 5% dextrose injection during simulated Y-site administration. Triplicate test samples were prepared by admixing 5 mL of palonosetron hydrochloride with 5 mL of the lorazepam or midazolam hydrochloride admixture. Physical stability was assessed by using a multistep evaluation procedure that included both turbidimetric and particulate measurements as well as visual inspection. Chemical stabililty was assessed by using stability-indicating high-performance liquid chromatographic analytical techniques that determined drug concentrations. Evaluations were performed initially upon mixing and again 1 and 4 hours after mixing. The samples were clear and colorless when viewed in normal fluorescent room light and when viewed with a Tyndall beam. Measured turbidity remained unchanged; particulate content was low and changed little. High-performance liquid chromatographic analysis revealed that palonosetron hydrochloride, lorazepam, and midazolam hydrochloride remained stable throughout the 4-hour test with no drug loss. Palonosetron hydrochloride is physically compatible and chemically stable with lorazepam or midazolam hydrochloride during Y-site administration.

Physical and chemical stability of palonosetron hydrochloride with topotecan hydrochloride and irinotecan hydrochloride during simulated y-site administration

The objective of this study was to evaluate the physical and chemical stabilty of undiluted palonosetron hydrochloride 50 micrograms/mL in combination with topotecan hydrochloride 0.1 mg/mL or irinotecan hydrochloride 1 mg/mL in 5% dextrose injection during simulated Y-site administration. Triplicate test samples were prepared by admixing 5 mL of palonosetron hydrochloride with 5 mL of the topotecan hydrochloride or irinotecan hydrochloride admixture. Physical stabilty was assessed by using a multistep evaluation preocdure that included both turbidimetric and particulate measurement as well as visual inspection. Chemical stability was assessed by using stability-indicating high-performance liquid chromatographic analytical techniques to determine drug concentrations. Evaluations were performed initially upon mixing and again 1 and 4 hour after mixing. The palonosetron hydrochloride-topotecan hydrochloride samples were clear and pale yellow when viewed in normal fluorescent room light. When viewed with a Tyndall beam, the samples had a slight haziness. The palonosetron hydrochloride-irinotecan hydrochloride samples were clear and colorless when viewed in in normal fluorescent room light and with a Tyndall beam. Measured turbidities remained unchanged; particulate contents were low and changed little. High-performance liquid chromatographic analysis found that palonosetron hydrochloride, topotecan hydrochloride, and irinotecan hydrochloride remained stable throughout the 4-hour test. Little drug loss was observed. Palonosetron hydrochloride is physically compatible and chemically stable with topotecan hydrochloride and with irinotecan hydrochloride during Y-site administration.

Physical and Chemical Stability of Palonosetron HCl in 4 Infusion Solutions

BACKGROUND

Palonosetron HCl is a selective 5-HT3 receptor antagonist used for the prevention of chemotherapy-induced nausea and vomiting. Palonosetron HCl may be diluted in an infusion solution for administraton. Consequently, stability information is needed for palonosetron HCl admixed in common infusion solutions.

OBJECTIVE

To evaluate the physical and chemical stability of palonosetron HCl in concentrations of 5 and 30 μg/mL in dextrose 5% injection, NaCl 0.9% injection, dextrose 5% in NaCl 0.45% injection, and dextrose 5% in lactated Ringer's injection.

METHODS

Triplicate test samples of palonosetron HCl at each concentration in each diluent were tested. Samples were stored and evaluated at appropriate intervals for up to 48 hours at room temperature (~23 °C) and 14 days under refrigeration (4 °C). Physical stability was assessed using turbidimetric and particulate measurement, as well as visual inspection. Chemical stability was assessed by HPLC.

RESULTS

All of the admixtures were initially clear and colorless when viewed in normal fluorescent room light and with a Tyndall beam. Measured turbidity and particulate content were low initially and remained low throughout the study. The drug concentration was unchanged in any of the samples at either temperature throughout the study.

CONCLUSIONS

Palonosetron HCl is physically and chemically stable in all 4 common infusion solutions for at least 48 hours at room temperature and 14 days under refrigeration.

Physical and Chemical Stability of Treprostinil Sodium Injection Packaged in Plastic Syringe pump Reservoirs

The objective of this study was to evaluate the physical and chemical stability of treprostinil (as sodium) injections in concentrations of 1, 2.5, 5 and 10 mg/mL packaged in MiniMed plastic syringe pump reservoirs. Test samples of treprostinil (as sodium) injections having concentrations of 1, 2.5, 5, and 10 mg/mL were packaged as 3 mL of drug solution in 3-mL MiniMed plastic syringe pump reservoirs, sealed with plastic tip caps and stored at -20 deg C, 4 deg C, 23 deg C and 37 deg C for 60 days. Evaluations for physical and chemical stability were performed initially and throughout the storage periods. Physical stability was assessed using visual observation in normal room light and using a high-intensity monodirectional light beam. In addition, turbidity and particle content were measured electronically. Chemical stability of the drug was evaluated by using a stability-indicating high-performance liquid chromatographic analytical technique. All samples of treprostinil (as sodium) injection remained free of visible precipitation throughout the study. Little or no change in haze level and in particulates of greater than or equal to 10 micrometers was found. Changes in treprostinil concentration were found to be small; treprostinil sodium concentrations were found to be 95% or greater over 60 days at all temperatures studied. Treprostinil (as sodium) injections at concentrations ranging from 1 to 10 mg/mL can be packaged in MiniMed plastic syringe reservoirs, stored and shipped with little or no loss of drug stability.

Stability of cefepime hydrochloride in AutoDose Infusion System bags

OBJECTIVE

To evaluate the physical and chemical stability of cefepime (as the hydrochloride) 1 g/100 mL and 4 g/100 mL admixed in NaCl 0.9% injection and packaged in AutoDose Infusion System bags.

DESIGN

Triplicate test samples of cefepime hydrochloride in NaCl 0.9% injection were packaged in ethylene vinyl acetate plastic containers, AutoDose bags, designed for use in the AutoDose Infusion System. Samples were stored protected from light and evaluated at appropriate intervals for up to 7 days at room temperature of approximately 23 degrees C and 30 days under refrigeration at 4 degrees C. Physical stability was assessed using turbidimetric and particulate measurement, as well as visual inspection. Chemical stability was assessed by HPLC.

RESULTS

All of the admixtures were initially clear and light yellow when viewed in normal fluorescent room light and with a Tyndall beam. Measured turbidity and particulate content were low initially but increased over time, eventually becoming a yellow or orange precipitate. The higher concentration precipitated earlier; refrigeration slowed precipitation for both test concentrations. HPLC analysis found that the 1-g/100 mL concentration maintained adequate stability for 2 days at 23 degrees C and up to 30 days at 4 degrees C. The 4-g/100 mL concentration maintained adequate stability for 1 day at room temperature and 7 days under refrigeration; however, unacceptable drug loss and precipitation developed after those time points.

CONCLUSIONS

Cefepime hydrochloride exhibited physical and chemical stability consistent with previous stability studies. The AutoDose Infusion System bags were not found to affect adversely the physical and chemical stability of this drug.

Stability of Clindamycin Phosphate in AutoDose Infusion System Bags

The physical and chemical stability of clindamycin phosphate 600mg/100mL and 1.2g/100mL admixed in 0.9% sodium chloride injection packaged in AutoDose Infusion System Bags was evaluated. Triplicate test samples were prepared by bringing the required amount of clindamycin phosphate injection to volume with 0.9% sodium chloride injection. A total of 100 mL of each of the test solutions was packaged in each of three ethylene vinyl acetate AutoDose bags designed for use in the AutoDose Infusion System. Samples were stored protected from light and were evaluated at appropriate intervals for up to 30 days at 4 deg C and up to 7 days at 23 deg C. Physical stability was assessed using a multistep evaluation procedure that included both turbidimetric and particulate measurement, as well as visual inspection. Chemical stability was assessed initially and at appropriate intervals during the study periods with stability-indicating high-performance liquid chromatographic anyalytical techinique based on the determination of drug concentrations. Throughout the study, the admixtures were clear and colorless when viewed in normal fluorescent room light and with a Tyndall beam. Measured turbidity and particulate content were low initially and exhibited little change throughout the study. The clindamycin phosphate samples exhibited no increase in measured particulates during the study period. High-performance liquid chromatographic analysis found little or no decomposition in the samples, and the analysis indicated that clindamycin phosphate in the test admixtures remained stable for 30 days at 4 deg C and for 7 days at 23 deg C. The clindamycin phosphate admixtures exhibited physical and chemical stability consistent with previous studies. The AutoDose Infusion System bags were not found to have an adverse effect on the physical and chemical stability of this drug.

Stability of Imipenem-Cilastatin Sodium in AutoDose Infusion System Bags

The objective of this study was to evaluate the physical and chemical stability of imipenem-cilastatin sodium 250 mg/100 mL and 500 mg/100 mL (of each drug component) admixed in 0.9% sodium chloride injection packaged in AutoDose Infusion System bags.

Triplicate test samples were prepared by bringing the required amount of imipenem-cilastatin sodium injection to volume with 0.9% sodium chloride injection. A total of 100 mL of each of the test solutions was packaged in each of three ethylene vinyl acetate (EVA) AutoDose bags designed for use in the AutoDose Infusion System for each storage condition. Samples were protected from light and evaluated at appropriate intervals for up to three days at 23°C and 14 days at 4°C.

Physical stability was assessed using a multistep evaluation procedure that included turbidimetric and particulate measurement in addition to visual inspection. Chemical stability was assessed with stability-indicating high performance liquid chromatography (HPLC) analytical techniques, based on initial drug concentrations and concentrations at appropriate intervals over the study periods. The admixtures were clear throughout the study when viewed in normal fluorescent room light and with a Tyndall beam. Measured turbidity and particulate content were low initially and exhibited little change throughout the study. HPLC analysis revealed extensive decomposition in the samples, with imipenem being the less stable component.

The instability of the imipenem-cilastatin sodium admixtures is consistent with previous studies. Admixtures stored under refrigeration should be used immediately upon warming to room temperature due to the rapid rate of imipenem decomposition. The AutoDose Infusion System bags were not found to affect adversely or improve the physical and chemical stability of this drug.

Stability of three cephalosporin antibiotics in AutoDose Infusion System bags

OBJECTIVE

To evaluate the physical and chemical stability of three commonly used cephalosporin antibiotic solutions packaged in AutoDose Infusion System bags stored and evaluated at appropriate intervals for up to 7 days at 23 degrees C and up to 30 days at 4 degrees C.

SETTING

Laboratory.

INTERVENTIONS

The test samples were prepared by adding the required amount of the cephalosporin antibiotic to the AutoDose Infusion System bags and diluting to the target concentration with 0.9% sodium chloride injection.

MAIN OUTCOME MEASURES

Physical stability and chemical stability based on drug concentrations initially and at appropriate intervals over periods of up to 7 days at 23 degrees C and up to 30 days at 4 degrees C.

RESULTS

All of the cephalosporin admixtures were clear when viewed in normal fluorescent room light and with a Tyndall beam. Measured turbidity and particulate content were low and exhibited little change. The cefazolin sodium-containing samples were colorless throughout the study. The admixtures with ceftazidime and ceftriaxone sodium had a slight yellow tinge initially, and the room temperature samples turned a frank yellow color after 5 days. The refrigerated samples did not change color. High-performance liquid chromatography analysis showed that cefazolin sodium and ceftriaxone sodium remained stable for 30 days and ceftazidime remained stable for 7 days at 4 degrees C. At room temperature, losses were much more rapid. Cefazolin sodium and ceftriaxone sodium retained at least 90% of their initial concentrations through 7 days and 5 days, respectively, when stored at 23 degrees C. Ceftazidime remained stable for only 1 day at 23 degrees C.

CONCLUSION

Cefazolin sodium, ceftazidime, and ceftriaxone sodium exhibited physical and chemical stabilities consistent with those found in previous studies of these drugs. The AutoDose Infusion System bags did not adversely affect the physical and chemical stabilities of these three cephalosporin antibiotics.

Stability of 4-aminopyridine and 3,4-diaminopyridine oral capsules

The objective of this study was to evaluate the chemical stability of 4-aminopyridine 5-mg capsules and 3,4-diaminopyridine 5-mg capsules under a variety of storage conditions. Each of the two drug preparations was extemporaneously prepared in hard gelatin capsules; lactose and micronized silica gel were used as excipients. Samples were stored under three conditions: refigeration at 4 deg C and protected from light for 6 months, protected from light at room temperature that ranged from 22 deg C to 24 deg C for 6 months, and at a temperature of 37 deg C and protected from light for 1 month. Once each month, visual inspection of the capsules and their powder contents was performed to identify observable changes (color, texture, etc) and the weight of the capsule content was measured individually. Chemical stability was assessed initially and at monthly intervals by means of a stability-indicating high-pressure liquid chromatography (HPLC) analytical technique based on the determination of drug content. No visible changes were observed in any of the samples under any of the storage conditions. The hard gelatin capsules remained clear and colorless, and the content of the capsules remained an off-white powder when viewed under normal fluorescent room light. Capsule content weight did not change during the study. Both 4-aminopyridine and 3,4-diaminopyridine exhibited excellent chemical stability under all study conditions. Little or no loss of drug content occurred in either product under refrigeration, at room temperature, and even at the elevated temperature of 37 deg C. The oral 5-mg capsules of 4-aminopyridine and 3,4 diaminopyridine did not undergo decomposition or other adverse changes within 6 months at refrigerated room temperature or within 1 month of storage at 37 deg C.

Stability of Gentamicin Sulfate and Tobramycin Sulfate in AutoDose Infusion System Bags

The objective of this study was to evaluate the physical and chemical stability of gentamicin sulfate 85mg/100mL and tobramycin sulfate 95mg/100mL, each of which was admixed in 0.9% sodium chloride injection and packaged in AutoDose Infusion System bags. Triplicate test samples were prepared by admixing the necessary amounts of the aminoglycoside antibiotics with a portion of 0.9% sodium chloride injection and bringing the admixture of each drug to a final volume of 100mL with additional 0.9% sodium chloride injection. The test solutions were packaged in ethylene vinyl acetate (EVA) plastic containers (AutoDose bags) designed for use in the AutoDose Infusion System. Samples were stored protected from light and were evaluated at appropriate intervals for up to 7 days at 23 deg C and up to 30 days at 4 deg C. Physical stability was assessed by means of a multistep evaluation procedure that included both turbidimetric and particulate measurement, as well as visual inspection. Chemical stability was assessed initially and at appropriate intervals during the study periods with stability-indicating high-performance liquid chromatographic (HPLC) analytical techniques based on the determination of drug concentrations. The aminoglycoside admixtures were clear and colorless when viewed in normal fluorescent room light and with a Tyndall beam. Measured turbidity and particulate content were low and exhibited little change. HPLC analysis indicated that both gentamicin sulfate and tobramycin sulfate remained stable for 30 days at 4 deg C and for 7 days at 23 deg C. Both gentamicin sulfate and tobramycin sulfate exhibited physical and chemical stability that were consistent with previous studies of those drugs. The AutoDose Infusion System bags did not adversely affect the physical and chemical stability of those aminoglycoside anitbiotics.

Physical and Chemical Stability of Morphine Sulfate 5mg/mL and 50mg/mL Packaged in Plastic Syringes

The objective of this study was to evaluate the physical and chemical stability of morphine sulfate in concentrations of 5 mg/mL in 0.9% sodium chloride injection and 50 mg/mL in both 0.9% sodium chloride injection and in sterile water for injection packaged in plastic syringes. Test samples of morphine sulfate 5-mg/mL and 50-mg/mL solutions were packaged as 20 mL of drug solution in 30-mL plastic syringes, sealed with plastic tip caps, and stored at 4 deg C and 23 deg C for 60 days. Test samples were also stored at -20 deg C and 37 deg C (temperature extremes that might be encountered during shipping) for 2 days. Evaluations of physical and chemical stability were performed initially and throughout the storage periods. Physical stability was assessed by means of visual observation in normal room light as well as with a high-intensity monodirectional light beam. In addition, turbidity and particle content were measured electronically. Chemical stabililty of the drug was evaluated by using a stability-indicating high-performance liquid chromatographic (HPLC) analytical technique. All samples of morphine sulfate 5-mg/mL solutions stored at 4 deg C, 23 deg C, and 37 deg C and the 50-mg/mL solutions stored at 23 deg C and 37 deg C remained free of precipitation throughout the study. In those solutions, little or no change in measured particulate burden or haze level was found, However, the solutions of morphine sulfate 50 mg/mL in 0.9% sodium chloride injection and in sterile water for injection exhibited an obvious precipitate within 2 to 4 days of storage at 4 deg C. Warming the solution to redissolve the visible precipitate left a substantial microparticulate content of up to 29,000 microparticulates/mL. When both morphine sulfate concentrations were frozen, precipitation was also noted. Upon thawing, the solutions yielded substantial measured microparticulate quantities of more than 20,000 microparticulates/mL in the 5-mg/mL concentration and more than 52,000 microparticulates/mL in the 50 mg/mL concentration. In addition, morphine sulfate 50mg/mL in both diluents exhibited a slight yellow discoloration after 30 days of storage at 23 deg C. Little or no loss of morphine sulfate occurred in any of the samples at any storage temperature throughout the study. Analysis of the samples after redissolving the visible precipitate in the low-temperature samples demonstrated that the morphine sulfate remained intact. Morphine concentrations were found to be 95% or greater over 60 days when stored at both 4 deg C and 23 deg C. In addition, morphine concentrations were greater than 97% when stored at -20 deg C, and they were 98% or greater when stored at 37 deg C after 2 days. However. exposure to low temperatures may result in precipitation, including microparticulate content that does not fully redissolve upon warming.

Physical and Chemical Stability of Hydromorphone Hydrochloride 1.5 and 80 mg/mL Packaged in Plastic Syringes

The objective of this study was to evaluate the physical and chemical stability of hydromorphone hydrochloride in concentrations of 1.5 and 80 mg/mL in 0.9% sodium chloride injection packaged in plastic syringes. Test samples of hydromorphone hydrochloride 1.5- and 80-mg/mL solutions were packaged as 20 mL of drug solution in 30-mL plastic syringes, sealed with plastic tip caps, and stored at 4 deg C and 23 deg C for 60 days and at -20 deg C and 37 deg C (temperature extremes that might be encounterd during shipping) for 2 days. Evaluations for physical and chemical stability were performed initially and throughout the storage periods. Physical stability was assessed by means of visual observation in normal room light with a high-intensity monodirectional light beam. In addition, turbidity and particle content were measured electronically. The chemical stability of the drug was evaluated by means of a stability-indicating high-performance liquid chromatographic (HPLC) analytical technique. All samples of hydromorphone hydrochloride remained free of visible precipitation throughout the study. Those solutions stored at 4 deg C, 23 deg C, or 37 deg C exhibited little or no change in measured particulate burden and haze level. Freezing the solution resulted in an increase in microparticulate content that did not redissolve when the solution was warmed at room temperature. Little or no loss of hydromorphone hydrochloride occurred in any of the samples at any storage temperature throughout the study. Hydromorphone hydrochloride concentrations were found to be 95% or greater over 60 days at both 4 deg C and 23 deg C; concentrations were greater than 97% at both -20 deg C and 37 deg C after 2 days. Hydromorphone hydrochloride solutions at concentrations ranging from 1.5 to 80 mg/mL in 0.9% sodium chloride injection can be packaged in plastic syringes, stored, and shipped with little or no loss of drug. Freezing should be avoided.

Physical and chemical stability of low and high concentrations of morphine sulfate with clonidine hydrochloride packaged in plastic syringes

The objective of this study was to evaluate the physical and chemical stability of morphine sulfate 5 mg/mL with clonidine hydrochloride 0.25 mg/mL in 0.9% sodium chloride injection and morphine sulfate 50 mg/mL with clonidine hydrochloride 4 mg/mL in sterile water for injection when packaged in plastic syringes. Test samples of morphine sulfate 5-mg/mL with clonidine hydrochloride 0.25-mg/mL and morphine sulfate 50-mg/mL with clonidine hydrochloride 4-mg/mL solutions were packaged as 20 mL of drug solution in 30-mL plastic syringes, sealed with plastic tip caps, and stored at 4 deg C and 23 deg C for 60 days. Test samples were also stored at -20 deg C and 37 deg C (temperature extremes that might be encountered during shiping) for 2 days. Evaluations for physical and chemical stability were performed initially and throughout the storage periods. Physical stability was assessed by means of visual observation in normal room light and with a high-intensity monodirectional light beam. In addition turbidity and particle content were measured electronically. Chemical stability of the drug was evaluated by means of a stability-indicating high-performance liquid chromatographic (HPLC) analytical technique. All samples of morphine sulfate 5-mg/mL with clonidine hydrochloride 0.25mg/mL solutions stored at 4 deg C, 23 deg C, and 37 deg C and the morphine sulfate 50-mg/mL with clonidine HCl 4-mg/mL solrtions stored at 23 deg C and 37 deg C remained free of precipitation throughout the study. Little or no change in measured particulate burden and haze level were found in those solutions. However, morphine sulfate 50 mg/ml with clonidine HCl 4 mg/mL stored at 4 deg C exhibited an obvious precipitate within 2 to 4 days. Warming the solution to redissolve the precipitate left a substantial microparticulate content that was measured to be more than 33,000 microparticulates/mL. Upon freezing, both high- and low- concentration samples precipitated and yielded substantial measured microparticulate quantities up to 35,000 microparticulates/mL in the low-concentration combination and 50,000 microparticulates/mL in the high-concentration combination. In addition, as with morphine sulfate 50 mg/mL alone, the high-concentration combination exhibited a slight yellow discoloration after 30 days of storage at 23 deg C. Little or no loss of morphine sulfate and clonidine hydrochloride occurred in any of the samples at any storage temperature throughout the study. Morphine concentrations were found to be about 98% or greater, and clonidine hydrochloride concentrations were about 97% or greater throughout the study period under each storage condition. Morphine sulfate solutions at concentrations ranging from 5 to 50 mg/mL combined with clonidine hydrochloride ranging from 0.25 to 4 mg/mL can be packaged in plastic syringes, stored and shipped with little or no loss of drug. However, freezing should be avoided.

Physical and chemical stability of low and high concentrations of morphine sulfate with bupivacaine hydrochloride packaged in plastic syringes

The objective of this study was to evaluate the physical and chemical stability of morphine sulfate 5 mg/mL with bupivacaine hydrochloride 2.5 mg/mL in 0.9% sodium chloride injection and morphine sulfate 50 mg/mL with bupivacaine hydrochloride 25 mg/mL in sterile water for injection packaged in plastic syringes. Test samples of morphine sulfate 5-mg/mL with bupicvacaine hydrochloride 2.5-mg/mL and morphine sulfate 50-mg/mL with bupivacaine hydrochloride 25-mg/mL solutions were packaged as 20 mL of drug solution in 30-mL plastic syringes, sealed with plastic tip caps, and stored at 4 deg C and 23 deg C for 60 days. Test samples were also stored at -20 deg C and 37 deg C (temperature extremes that might be encountered during shipping) for 2 days. Evaluations for physical and chemical stability were performed initially and throughout the storage periods. Physical stability was assessed by means of visual observation under normal room light and with a high-intensity monodirectional light beam. In addition, turbidity and particle content were measured electronically. Chemical stability of the drug was evaluated with a stability-indicating high-performance liquid chromatographic (HPLC) analytical technique. All test samples remained free of visible precipitation throughout the study. The inclusion of the bupivacaine hydrochloride prevented the precipitation of morphine sulfate that occurs at a lower storage temperature. For solutions stored at 4 deg C, 23 deg C, and 37 deg C, little or no change in measured particulate burden and haze level were found. However, samples stored frozen at -20 deg C exhibited a substantial microparticulate content upon thawing that was measured to be nearly 12,000 microparticulates/mL. Most samples were clear and colorless throughout the study. However, morphine sulfate 50 mg/mL exhibited a slight yellow discoloration after 7 days of storage at 23 deg C. Little or no loss of morphine sulfate and bupivacaine hydrochloride occurred in any of the samples at any storage temperature throughout the study. Morphine concentrations were found to be about 97% or greater, and bupivacaine hydrochloride concentrations were about 95% or greater throughout the study period under each storage condition. Morphine sulfate solutions at concentrations ranging from 5 mg/mL to 50 mg/mL combined with bupivacaine hydrochloride 2.5 mg/mL to 25 mg/mL can be packaged in plastic syringes stored, and shipped with little or no loss of drug. However, freezing should be avoided.

Compatibility and stability of linezolid injection admixed with gentamicin sulfate and tobramycin sulfate

The purpose of this study was to evaluate the physical compatibility and chemical stability of linezolid 200 mg/100mL admixed with gentamicin sulfate 80 mg and tobramycin sulfate 80 mg over 7 days at 4 deg C and 23 deg C. The test samples were prepared by adding the required amount of the aminoglycoside antibiotic to bags of linezolid injection 200mg/100mL. Physical and chemical stability based on drug concentrations initially and after 1, 3, 5, and 7 days of storage at 4 deg C ad 23 deg C were evaluated. The linezolid-aminoglycoside admixtures were clear when viewed in normal fluorescent room light and with a Tyndall beam. Measured turbidity and particulate content were low and exhibited little change. The admixtures remained colorless throughout the study. High-performance liquid chromatography analysis indicated little or no loss of linezolid in any sample stored at either temperature throughtout the study. Gentamicin sulfate and tobramycin sulfate in the linezolid admixtures at 4 deg C remained stable for 7 days, but at 23 deg C gentamicin sulfate was stable for 5 days and tobramycin sulfate was stable for only 1 day before aminoglycoside losses exceeded 10%. Admixtures of linezolid 200mg/100mL with gentamicin sulfate 80 mg and tobramycin sulfate 80 mg were physically compatible and chemically stable for at least 7 days when stored at 4 deg C and for 5 days or 1 day, repectively, at 23 deg C.

Adequacy of a new chlorhexidine-bearing polyurethane central venous catheter for administration of 82 selected parenteral drugs

OBJECTIVE

To screen 82 commonly used parenteral medications for compatibility with a new chlorhexidine-bearing central venous catheter, the ARROWg+ard Blue Plus. Evaluations were performed for completeness of drug delivery and impact, if any, of the drugs on the amount of chlorhexidine removed from the internal lumens.

DESIGN

Drug solutions were prepared in dextrose 5% injection or NaCl 0.9% at common concentrations. Three 10-mL aliquots of each drug solution were delivered over 10 minutes, one aliquot through each lumen of the triple-lumen catheter. The initial drug concentrations of the admixtures and the effluent samples were analyzed by HPLC for chlorhexidine content and for the amount of drug delivered relative to its initial concentration.

RESULTS

The delivery of the infusion solutions alone through sample catheters resulted in no more than trace amounts of chlorhexidine in the solution. Background amounts ranged from < 2.5 to 6.1 micrograms/mL in the first 10 mL of solution. Administration of none of the drugs tested resulted in a substantial increase in chlorhexidine delivery. Furthermore, delivery of most of the drugs was at least 95% and usually was in excess of 97% of the initial concentration. Concentrations of five drugs, amikacin sulfate, cefoperazone sodium, cefotaxime sodium, cefepime HCl, and netilmicin sulfate were somewhat lower than the initial concentration (range 91-95%), but were still considered acceptable.

CONCLUSIONS

The ARROWg+ard Blue Plus central venous catheter can be recommended for use with all of the 82 parenteral drugs tested.

Compatibility and stability of linezolid injection admixed with three quinolone antibiotics

OBJECTIVE

To evaluate the physical compatibility and chemical stability of linezolid 200 mg/100 mL admixed with ciprofloxacin 400 mg, ofloxacin 400 mg, and levofloxacin 500 mg for seven days at 4 and 23 degrees C.

METHODS

The test samples were prepared by adding the required amount of the quinolone antibiotic to bags of linezolid injection. Evaluations for physical and chemical stability were performed initially and after one, three, five, and seven days of storage at temperatures of 4 and 23 degrees C. Physical stability was assessed using visual observation in normal light and using a high-intensity monodirectional light beam. In addition, turbidity and particle content were measured electronically. Chemical stability of the drugs was evaluated by using stability-indicating HPLC analytical techniques.

RESULTS

The linezolid admixtures with levofloxacin and ofloxacin were clear and pale yellow when viewed in normal fluorescent room light, and slightly hazy with a green cast when viewed using a Tyndall beam. Measured turbidity and particulate content were low and exhibited little change. HPLC analysis found no loss of the drugs in any sample stored at either temperature throughout the study. The linezolid admixtures with ciprofloxacin stored at room temperature (23 degrees C) were clear and nearly colorless in normal room light and when viewed using a Tyndall beam. They exhibited little or no change in measured turbidity or particulate content during the study period. HPLC analysis found no loss of either drug in seven days. However, the refrigerated samples were only compatible for 24 hours and developed a gross white precipitate thereafter.

CONCLUSIONS

Admixtures of linezolid 200 mg/100 mL with levofloxacin 500 mg and with ofloxacin 400 mg were physically compatible and chemically stable for at least seven days stored at 4 and 23 degrees C. Admixtures of linezolid with ciprofloxacin 400 mg were compatible and stable for seven days at 23 degrees C, but ciprofloxacin precipitation occurred after 24 hours stored under refrigeration. Linezolid/ciprofloxacin admixtures should not be stored under refrigeration.

Compatibility and stability of linezolid injection admixed with aztreonam or piperacillin sodium

OBJECTIVE

To evaluate the physical compatibility and chemical stability of linezolid (Zyvox-Pharmacia) 200 mg/100 mL admixed with aztreonam (Azactam-Squibb) 2 grams and separately with piperacillin sodium (Pipracil-Lederle) 3 grams over 7 days at 4 degrees C and 23 degrees C.

DESIGN

Controlled experimental trial.

SETTING

Laboratory.

INTERVENTIONS

Test samples were prepared by adding the required amount of aztreonam or piperacillin sodium to separate bags of linezolid injection 200 mg/100 mL.

MAIN OUTCOME MEASURES

Physical compatibility and chemical stability based on drug concentrations initially and after 1, 3, 5, and 7 days of storage at 4 degrees C and 23 degrees C.

RESULTS

All of the linezolid admixtures with aztreonam and with piperacillin sodium were clear when viewed in normal fluorescent room light and with a Tyndall beam. Measured turbidity and particulate content were low and exhibited little change throughout the study at both storage temperatures. High-performance liquid chromatography analysis found little or no loss of linezolid in any sample stored at either temperature throughout the study. Aztreonam in the linezolid admixtures was stable for 7 days, exhibiting less than 5% loss at 4 degrees C and 9% loss at 23 degrees C. Piperacillin sodium in the linezolid admixtures was stable for 7 days at 4 degrees C, exhibiting no loss, but was stable for only 3 days at 23 degrees C with losses of about 5%. Losses had increased to 9% to 12% after 5 days of storage at room temperature.

CONCLUSION

Admixtures of linezolid 200 mg/100 mL with aztreonam 2 grams or piperacillin sodium 3 grams were physically compatible and chemically stable for at least 7 days stored at 4 degrees C and for 7 days or 3 days, respectively, at 23 degrees C.

Compatibility and stability of linezolid injection admixed with three cephalosporin antibiotics

OBJECTIVE

To evaluate the physical compatibility and chemical stability of linezolid (Zyvox-Pharmacia) 200 mg/100 mL admixed with cefazolin sodium 1 gram, ceftazidime 2 grams, and ceftriaxone sodium 1 gram for 7 days at 4 degrees C and 23 degrees C.

DESIGN

Controlled experimental trial.

SETTING

Laboratory.

INTERVENTIONS

The test samples were prepared by adding the required amount of the cephalosporin antibiotic to bags of linezolid injection 200 mg/100 mL.

MAIN OUTCOME MEASURES

Physical stability and chemical stability based on drug concentrations initially and after 1, 3, 5, and 7 days of storage at 4 degrees C and 23 degrees C protected from light.

RESULTS

All of the linezolid admixtures with cephalosporins were clear when viewed in normal fluorescent room light and with a Tyndall beam. Measured turbidity and particulate content were low and exhibited little change. The cefazolin sodium-containing samples were colorless throughout the study. The admixtures with ceftazidime and ceftriaxone sodium had a slight yellow tinge initially, and the room temperature samples became a frank yellow color after 5 days. The refrigerated samples did not change color. High-performance liquid chromatography analysis found little or no loss of linezolid in any sample stored at either temperature throughout the study. Cefazolin sodium and ceftazidime in the linezolid admixtures at 4 degrees C remained stable for 7 days, but at 23 degrees C cefazolin sodium was stable for 3 days and ceftazidime for only 24 hours before cephalosporin decomposition exceeded 10%. Ceftriaxone sodium was less stable in the admixtures; 10% loss occurred in 3 days at 4 degrees C and more than 20% loss occurred in 24 hours at 23 degrees C.

CONCLUSION

Admixtures of linezolid 200 mg/100 mL with cefazolin sodium 1 gram and ceftazidime 2 grams were physically compatible and chemically stable for at least 7 days stored at 4 degrees C protected from light and for 3 days and 1 day, respectively, at 23 degrees C protected from light. Admixtures of linezolid with ceftriaxone sodium 1 gram exhibited a rapid rate of cephalosporin loss at 23 degrees C, which precludes admixture of the two drugs.

Compatibility and stability of paclitaxel combined with doxorubicin hydrochloride in infusion solutions

OBJECTIVE

To evaluate the physical compatibility and chemical stability of paclitaxel at concentrations of 300 and 1200 micrograms/mL with doxorubicin hydrochloride 200 micrograms/mL in NaCl 0.9% injection and dextrose 5% injection over 7 days at 4, 23, and 32 degrees C.

DESIGN

The test samples were prepared in polyolefin bags of the infusion solutions at the required drug concentrations. Evaluations were performed initially and after 4 hours, and 1, 3, 5, and 7 days of storage at 4, 23, and 32 degrees C for physical and chemical stability. Physical stability was assessed by using visual observation in normal fluorescent light and a high-intensity monodirectional light beam. In addition, turbidity and particle content were measured electronically. Chemical stability of the two drugs was evaluated by using two stability-indicating HPLC analytic techniques.

RESULTS

All samples were physically stable through 1 day. However, microcrystalline precipitation of paclitaxel occurred within 3 days in some samples and within 5 days in all samples. Paclitaxel concentrations remained at more than 97% in all samples throughout the study. Doxorubicin hydrochloride also was stable throughout the study period, remaining above 90% in all samples at all storage temperatures.

CONCLUSIONS

Admixtures of paclitaxel 300 and 1200 micrograms/mL with doxorubicin hydrochloride are limited in their utility time by paclitaxel microcrystalline precipitation. All combinations were physically and chemically stable for at least 24 hours at 4, 23, and 32 degrees C.

Compatibility of Paclitaxel injection diluent with two reduced-phthalate administration sets for the acclaim pump

The purpose of this project was to evaluate the compatibility of paclitaxel admixtures with the two reduced-phthalate administration sets designed for use with the Acclaim Infusion Control Device. The first is a nitroglycerin set composed of polyethylene tubing, while the second is made using tris(2-ethyl-hexyl) trimellitate (TOTM)-plasticized polyvinyl chloride tubing. Both sets utilize a diethylhexyl phthalate (DEHP)-plasicized pumping segment. The potential for extraction of DEHP from the pumping segments and TOTM plasticizer from the plastic matrix by the Cremophor EL surfactant present in the paclitaxel injection was evaluated. Diethylhexyl phthalate and TOTM plasticizer extraction was tested using the paclitaxel diluent at concentrations equivalent to 0.3 and 1.2 mg/mL over three-hour and four-day infusions. All samples were prepared in triplicate in polyolefin bags of 5% dextrose injection and deliverd through the administration sets into glass collection flasks. Both DEHP and TOTM content were determined using high-performance liquid chromatographic methods. None of the admixtures delivered rapidly over three hours or slowly over four days through the TOTM-plasticized set exhibited any detectable TOTM. Similarly, no DEHP was detected in the effluent form either set with the simulated 0.3-mg/mL admixtures delivered over three hours. The simulated 1.2-mg/mL admixture delivered over three hours yielded only a barely detectable, but not quantifiable, trace of DEHP. However, slow delivery of both concentrations over four days through both sets resulted in leached DEHP in concentrations ranging from about 30 to 150 micrograms/mL at both one and four days. The two reduced-phthalate administration sets tested in this study are suitable for the administration of paclitaxel infusions of short duration, for up to three hours. However, the sets cannot be recommended for administration over longer-duration delivery times ranging from one to four days due to leaching of DEHP plasticizer from the pumping segments.

Stability of cisatracurium besylate in vials, syringes, and infusion admixtures

The stability of cisatracurium besylate was studied. Cisatracurium (as besylate) 2 mg/mL in 5- and 10-mL unopened vials and 10 mg/mL in 20-mL unopened vials, as well as 3 mL of solution from additional 2-mg/mL vials, repackaged in 3-mL sealed plastic syringes, was stored at 4 and 23 degrees C in the dark and in normal fluorescent room light. Admixtures of cisatracurium (as besylate) 0.1, 2, or 5 mg/mL in polyvinyl chloride (PVC) minibags of 5% dextrose injection or 0.9% sodium chloride injection were stored at 4 and 23 degrees C in normal fluorescent room light. Triplicate samples for each storage condition were taken initially and at 1, 3, 5, 7, 14, 21, and 30 days; samples from vials were also removed at 45 and 90 days. Solutions were stored in sterile vials at -70 degrees C and then thawed at room temperature before analysis of chemical stability by high-performance liquid chromatography. Physical stability was assessed as well. Cisatracurium besylate was physically stable in all samples throughout the study. Cisatracurium (as besylate) 2 mg/mL exhibited drug losses at 23 degrees C in vials at 45 days and in syringes at 30 days. Cisatracurium (as besylate) 0.1, 2, and 5 mg/mL in 5% dextrose injection and in 0.9% sodium chloride injection was stable for at least 30 days at 4 degrees C, but substantial drug losses occurred at 23 degrees C. Admixtures prepared with cisatracurium (as besylate) 0.1 mg/mL and with 5% dextrose injection exhibited the greatest losses. Cisatracurium besylate was stable in most samples for at least 30 days at 4 and 23 degrees C; admixtures containing cisatracurium (as besylate) 0.1 or 2 mg/mL exhibited substantial drug loss at 23 degrees C.

Paclitaxel Compatibility with the IV Express Filter Unit

The purpose of this project was to evaluate the compatibility of paclitaxel infusions with the IV Expres filter unit, a 0.22-micrometer intravenous solution filter (Millipore Corporation, Bedford, MA). The potential for extraction of diethylhexyl phthalate platicizer from the filter unit by the Cremaophor EL surfactant present in the paclitaxel injection and the potential for loss of paclitaxel to filter unit components due to sorption were evaluated. Plasticizer extraction was tested using the paclitaxel diluent at a concentration equivalent to 1.2 mg/mL over a three-hour simulated infusion. Paclitaxel delivery was evaluated in admixtures containing paclitaxel 0.3 mg/mL. All samples were prepared in triplicate in polyolefin bags of 5% dextrose injections and delivered through IV Express filter units attached to nonpolyvinyl chloride administration sets designed for the adminstration of paclitaxel infusions. The samples were collected in glass collection flasks. Both plasticizer and paclitaxel content were determined using specific high-performance liquid chromatographic methods. None of the admixtures delivered over three hours through the IV Express filter unit exhibited any detectable plasticizer. Further, no loss of paclitaxel due to soption to any filter commponent occurred; the full amount of paclitaxel was deliverd in the simulated ifusions. The IV Express filter unit tested in this study is suitable for the administration of paclitaxel infusions over three hours.

Compatibility and stability of paclitaxel combined with cisplatin and with carboplatin in infusion solutions

OBJECTIVE

To evaluate the physical compatibility and chemical stability of paclitaxel at concentrations of 0.3 and 1.2 mg/mL with cisplatin 0.2 mg/mL in NaCl 0.9% injection and with carboplatin 2 mg/mL in NaCl 0.9% injection and dextrose 5% injection over 7 days at 4, 23, and 32 degrees C.

DESIGN

The test samples were prepared in polyolefin bags of the infusion solutions at the required drug concentrations. Evaluations were performed initially and after 4 hours, and 1, 3, 5, and 7 days of storage at temperatures of 4, 23, and 32 degrees C for physical and chemical stability. Physical stability was assessed by using visual observation in normal light and using a high-intensity monodirectional light beam. In addition, turbidity and particle content were measured electronically. Chemical stability of the three drugs was evaluated by using three stability-indicating HPLC analytical techniques.

RESULTS

All samples were physically stable through 1 day. However, microcrystalline precipitation of paclitaxel occurred in 3 days in some samples and within 5 days in all samples. Paclitaxel concentrations remained above 90% in all samples throughout the study. Cisplatin admixtures exhibited paclitaxel concentration-dependent decomposition with cisplatin losses of approximately 5-8% in 4 hours and approximately 20% in 1 day at 23 and 32 degrees C in the paclitaxel 1.2 mg/mL admixtures. With paclitaxel 0.3 mg/mL in the admixtures, cisplatin losses were about 10% in 7 days at these temperatures. Carboplatin in admixtures with both concentrations of paclitaxel was stable for 7 days at 4 degrees C, but sustained losses of about 10% and 12% in 3 days at 23 and 32 degrees C, respectively.

CONCLUSIONS

Admixtures of paclitaxel 0.3 and 1.2 mg/mL with cisplatin and carboplatin are limited in their utility time by both paclitaxel microcrystalline precipitation and decomposition of cisplatin and carboplatin. The admixture of paclitaxel 1.2 mg/mL with cisplatin 0.2 mg/mL in NaCl 0.9% injection exhibits unacceptable cisplatin loss in 24 hours. All other combinations were physically and chemically stable for at least 24 hours at 4, 23, and 32 degrees C.

Development of clonidine hydrochloride injections for epidural intrathecal administration

The purpose of this study was to describe and document the development of several concentrations of clonidine hydrochloride injection for evaluation as epidural and intrathecal injections in clinical trials for the control of intractable pain. Bulk clonidine hydrochloride prepared under Good Manufacturing Practices conditions was formulated as simple aqueous solutions in 0.9% sodium chloride injection having concentrations of 0.15, 0.5 and 1.5 mg/mL. The low concentration served as the starting concentration for low drug delivery, with the highter concentrations needed to accommodate increasing rates of drug delivery. All three concentrations exhibited natural pH values of about 6 to 6.5 and were adjusted to a target pH of 6.5 with sodium hydroxide, if necessary. The measured osmolalities were about 285 mOsm/kg, nearly isotonic. The injections were filtered through 0.22 micormeter filters and packaged in 20mL, Type-1, flint glass vials with rubber stoppers. The vials were terminally sterilized by autoclaving at 121 deg C and 15 psi for 30 minutes. Using a stability-indicating, high-performance liquid chromatography analytical technique based on the official USP method, we observed no loss of clonidine hydrochloride in any of the development vials at the concentrations of 0.15, 0.5 and 1.5 mg/mL after preparation and autoclaving. Similarly, shelf-life studies on two small batches each of the 0.15- and 0.5-mg/mL concentrations have shown little or no loss of clonidine hydrochloride after three months' storage at 37 deg C and for up to 24 months at 4 and 23 deg C. Shelf-life studies are continuing. Clonidine hydrochloride 0.15-, 0.5-, and 1.5-mg/mL injections have been developed as epidural and intrathecal injections in clinical trials to control intractable pain. The injections are easily formulated and stable during compounding and storage.

Rapid loss of fentanyl citrate admixed with fluorouracil in polyvinyl chloride containers

OBJECTIVE

To study the physical compatibility and chemical stability of fluorouracil 1 and 16 mg/mL with fentanyl citrate 12.5 micrograms/mL in dextrose 5% and in sodium chloride 0.9% injection.

DESIGN

Test solutions of the drugs in dextrose 5% injection and in sodium chloride 0.9% injection were prepared in triplicate and stored at -20, 4, 23, and 32 degrees C. Samples were removed immediately and at various times over 7 days and stored at -70 degrees C until analyzed. Physical compatibility was assessed visually and by measuring turbidity with a color-correcting turbidimeter; particle content was measured with a light-obscuration particle sizer and counter. Chemical stability was determined by measuring the concentration of each drug in the test solutions in duplicate with stability-indicating HPLC.

RESULTS

Fentanyl citrate was rapidly lost when admixed with fluorouracil in polyvinyl chloride (PVC) containers, losing about 25% in the first 15 minutes and about 50% in the first hour. The loss of fentanyl citrate was so rapid that accurate time zero determinations were not possible. The extent of fentanyl loss increased with time and occurred more rapidly at the higher temperatures (i.e., 23, 32 degrees C). Losses of 70% or more occurred in all samples within 24 hours. Fentanyl underwent rapid sorption to the containers at the high pH (9.0-9.5) of the fluorouracil admixtures. Adjusting the pH of a fentanyl citrate solution (containing no fluorouracil) in PVC containers to pH 9 with sodium hydroxide also resulted in rapid sorption loss. Fentanyl citrate sorption did not occur when admixtures were prepared in polyethylene containers. Fluorouracil remained stable for at least 7 days at all temperatures. There were no visual or subvisual changes in turbidity or particle content in any of the test solutions at any time.

CONCLUSIONS

When admixed with fluorouracil 1 and 16 mg/mL in dextrose 5% injection and sodium chloride 0.9% injection, fentanyl citrate 12.5 micrograms/mL underwent rapid and extensive loss due to sorption to the PVC containers, making the combination unacceptable within minutes of mixing. The sorption results from the alkaline pH of the admixture and, presumably, could occur from the admixture of fentanyl citrate with any sufficiently alkaline drug.

Stability of thiotepa (lyophilized) in 5% dextrose injection at 4 and 23 degrees C

The stability of thiotepa (lyophilized) 0.5 and 5 mg/mL in 5% dextrose injection was studied. Vials of lyophilized thiotepa were reconstituted with sterile water for injection to yield a solution with a nominal 10-mg/mL drug concentration. The reconstituted solution was filtered and diluted in 5% dextrose injection in polyvinyl chloride and polyolefin bags to nominal thiotepa concentrations of 0.5 and 5 mg/mL. Triplicate test admixtures were prepared and stored at 4 or 23 degrees C in normal fluorescent light. Initially and after four and eight hours and 1, 3, 7, and 14 days, samples were removed for visual evaluation, turbidimetry, and stability-indicating high-performance liquid chromatography. No incompatibilities were observed. Admixtures containing thiotepa 0.5 mg/mL retained at least 90% of the initial drug concentration for eight hours at either temperature in either type of container; after 24 hours, losses ranged from 10% to 17%. Thiotepa in the 5-mg/mL admixtures was stable for 3 days at 23 degrees C and 14 days at 4 degrees C in both container types. Thiotepa (lyophilized) 0.5 mg/mL in 5% dextrose injection was stable for eight hours at 4 or 23 degrees C. Thiotepa (lyophilized) 5 mg/mL in 5% dextrose injection was stable for 3 days at 23 degrees C and 14 days at 4 degrees C.

Stability and compatibility of fluorouracil with morphine sulfate and hydromorphone hydrochloride

OBJECTIVE

To study the physical compatibility and chemical stability of fluorouracil 1 and 16 mg/mL with morphine sulphate 1 mg/ml and with hydromorphone hydrochloride 0.5 mg/mL in dextrose 5% injection and in NaCl 0.9% injection.

DESIGN

Test solutions of the drugs in dextrose 5% and in NaCl 0.9% were prepared in triplicate and stored at -20, 4, 23, and 32 degrees C. Samples were removed immediately and at various time points over 35 days and stored at -70 degrees C until analyzed. Physical compatibility was assessed visually and by measuring turbidity with a color-correcting turbidimeter and particle content with a light-obscuration particle sizer and counter. Chemical stability was determined by measuring the concentration of each drug in the test solutions in duplicate with stability-indicating HPLC.

RESULTS

The morphine test solutions all rapidly developed crystalline precipitation when admixed with fluorouracil. Further, substantial loss of morphine content, usually around 60-80%, occurred in all samples within 24 hours at all temperatures. There were no visual or subvisual changes in turbidity or particle content in any of the fluorouracil with hydromorphone test solutions at any of the time points. Further, there was no loss of fluorouracil over 7 days at 32 degrees C and 35 days at 23, 4, and -20 degrees C. Hydromorphone also was stable for 7 days at 32 degrees C and for 35 days at the other temperatures when combined with fluorouracil 1 mg/mL and at -20 and 4 degrees C with fluorouracil 16 mg/mL. However, with fluorouracil 16 mg/mL, hydromorphone was stable only for 3 days at 32 degrees C and for 7 days at 23 degrees C, exhibiting approximately 10% loss after those times.

CONCLUSIONS

When admixed in dextrose 5% injection and NaCl 0.9% injection, fluorouracil 1 and 16 mg/mL and morphine 0.5 mg/mL were immediately physically incompatible in all samples resulting in substantial loss of morphine content as precipitated crystals. Fluorouracil 1 mg/mL plus hydromorphone 0.5 mg/mL were compatible and stable for at least 7 days at 32 degrees C and for at least 35 days at 23, 4 and -20 degrees C. Admixed with fluorouracil 16 mg/mL, hydromorphone was stable for 3 days at 32 degrees C, 7 days at 23 degrees C, and 35 days at 4 and -20 degrees C.

Compatibility and stability of aztreonam and vancomycin hydrochloride

The physical compatibility and chemical stability of aztreonam and vancomycin hydrochloride when combined at clinically used high and low concentrations were studied. Admixtures consisting of aztreonam 4 mg/mL and vancomycin 1 mg/mL (as the hydrochloride salt) in 5% dextrose injection, aztreonam 4 mg/mL and vancomycin 1 mg/mL in 0.9% sodium chloride injection, aztreonam 40 mg/mL and vancomycin 10 mg/mL in 5% dextrose injection, and aztreonam 40 mg/mL and vancomycin 10 mg/mL in 0.9% sodium chloride injection were prepared in triplicate in polyvinyl chloride containers. Three containers of each type of admixture were stored at 4, 23, and 32 degrees C. Samples were removed immediately and at various time points over 31 days. Compatibility was assessed by visual examination, with a turbidimeter, and with a particle sizer-counter. Stability was determined by stability-indicating high-performance liquid chromatography (HPLC). All the admixtures initially appeared clear to the unaided eye after the disappearance of a transient white swirl in the high-concentration admixtures (aztreonam 40 mg/mL and vancomycin 10 mg/mL). However, the high-concentration admixtures immediately developed unacceptable levels of a microcrystalline precipitate when viewed with a high-intensity fiber-optic light source. Easily visible gross turbidity and precipitation formed after various periods but often within 24 hours. HPLC showed aztreonam 4 mg/mL and vancomycin 1 mg/mL in 5% dextrose injection to be a stable combination for 7 days at 32 degrees C, 14 days at 23 degrees C, and 31 days at 4 degrees C. In 0.9% sodium chloride injection, the drugs in the low-concentration admixtures were stable for 7 days at 32 degrees C and for 31 days at 4 and 23 degrees C. Stability of the combination in the high-concentration admixtures was maintained for 3 days at 23 and 32 degrees C and for 14 days at 4 degrees C. Aztreonam and vancomycin hydrochloride were considerably less compatible and stable in the high-concentration admixtures than in the low-concentration ones.

Compatibility of ondansetron hydrochloride with meperidine hydrochloride for combined administration

OBJECTIVE

To determine the physical compatibility and chemical stability of ondansetron hydrochloride 0.1 and 1 mg/mL with meperidine hydrochloride 4 mg/mL admixed in NaCl 0.9% injection USP.

DESIGN

Triplicate test solutions of the drugs in NaCl 0.9% injection USP were prepared and stored at 4, 22, and 32 degrees C. Samples were removed initially and at various time points over 31 days and were stored at -70 degrees C until they were analyzed. Physical compatibility was assessed by measuring solution turbidity with a color-correcting turbidimeter and particle content with a light-obscuration particle sizer/counter, as well as by visual assessment. Chemical stability of the drugs was determined using a stability-indicating HPLC analytic method. Duplicate determinations were performed on each sample to measure the concentration of each drug.

RESULTS

All admixtures were found to exhibit no visual or subvisual changes of consequence in turbidity or particle content at all observation points. Further, little or no loss of any of the drugs occurred in any concentration throughout the study.

CONCLUSIONS

The physical compatibility and chemical stability of ondansetron hydrochloride with meperidine hydrochloride under the conditions of this study have been established for 7 days at 32 degrees C and 31 days at 4 and 22 degrees C.

Incompatibility of fluorouracil with leucovorin calcium or levoleucovorin calcium

The physical compatibility of fluorouracil mixed with leucovorin calcium or levoleucovorin calcium, undiluted and modestly diluted with 5% dextrose injection, was evaluated. Fluorouracil 50 mg/mL was combined in duplicate with leucovorin or levoleucovorin 20 mg/mL (as the calcium salt) in 250-mL polyvinyl chloride (PVC) portable-pump reservoirs in six volume ratios, either undiluted or diluted with 5% dextrose injection (to a final volume 25% greater than the drug volume). Duplicate reservoirs of each combination were stored for seven days at 4, 23, or 32 degrees C. Samples were evaluated visually with a high-intensity monodirectional light beam to observe development of particulates. Turbidimetry and light-obscuration particle counting and sizing also were used to evaluate compatibility. Small amounts of tiny crystalline particles developed in most of the combinations, usually by four days. In some cases, the particles could be seen in normal diffuse room light. Particle content was greater with higher leucovorin concentrations and over longer storage periods. Storage temperature did not play a consistent role in particle development. Fluorouracil and leucovorin calcium or levoleucovorin calcium were not compatible when stored in PVC reservoirs at 4, 23, or 32 degrees C.

Effect of a non-protein fraction from an extract of the inflamed skin of rabbits inoculated with vaccinia virus (Neurotropin) on Meth A-induced delayed type hypersensitivity

The effect of a non-protein fraction from an extract of inflamed skin of rabbits inoculated with vaccinia virus (Neurotropin, NSP) was studied on Meth A tumor-induced delayed type hypersensitivity (Meth A-DTH) in BALB/c mice. NSP enhanced the Meth A-DTH. NSP also enhanced the DTH suppressed with 5-fluorouracil (5-FU). Moreover, NSP inhibited the fatal effect of 5-FU and restored the decrease of body weight caused by 5-FU. However, NSP reduced partially but significantly the suppression of the tumor growth by 5-FU. NSP may be useful for cancer treatment in combination with chemotherapeutic agents, if NSP does not inhibit their antitumor activity.

Effect of CV-3988, a specific antagonist against platelet activating factor, on homologous passive cutaneous anaphylaxis in the mouse ear

Effect of CV-3988, a specific antagonist against platelet activating factor (PAF), on homologous passive cutaneous anaphylaxis (PCA) elicited in the mouse ear was investigated. PAF caused a potent increase in vascular permeability in the mouse ear. The potency was slightly lower than that of serotonin but higher than those of histamine, leukotriene (LT) C4, LTD4, prostaglandin (PG) E1 and PGE2 on a weight basis. The increased vascular permeability caused by PAF was inhibited by CV-3988 in a dose-dependent manner. CV-3988 did not affect the increase in vascular permeability caused by histamine or serotonin. IgG1 antibody-mediated PCA in the mouse ear was inhibited by CV-3988, although it did not affect IgE antibody-mediated PCA. These results suggest a possibility that PAF might be involved in IgG1 antibody-mediated PCA in the mouse.