- Email: [email protected]
A new genomic approach to monitor toxicity of candidate compounds for development
Poster Session 2D. Pharma ceuticals
IP2D94 I
N
PRECLINICAL TOXICOLOGY OF BIOVECTOR NANOPARTlCLES: PART II, LOCAL TOLERANCE, GENETIC TOXICOLOGY ANDPHARMACOKINETICS
R. Kravtzoff *, T. Appelqvist, H. Haddouk, X. Manciaux, G. Cholet, 1. De Miguel, M. Major, D. Betbeder, R. Forster. Biovector Therapeutics, BP 169,31676 Labege; crr Centre International de Toxicologie, BP 563, Miser ey. 27005 Evreux, France Biovector" nanoparticles are a family of cross-linked polysaccharide nanoparticles surrounded by a lipid layer, developed as a vehicle for drug delivery. The local tolerance, genetic toxicology and pharmacokinetics of a cationic Biovector" with high charge density have been evaluated prior to human healthy volunteer studies by the intranasal route. The local tolerance was studied following twice daily intranasal administration to New Zealand rabbits over a period of seven days. The local tolerance was good and there were no treatment-related clinical or histopathology findings. The potential mutagenicity of Biovector" nanoparticles was studied in the Ames test and the mouse micronucleus test: negative results were obtained in both studies. The plasma kinetics and tissue distribution of radiolabelled Biovector" nanoparticles was studied after intranasal administration to rats. Systemic absorption was low, and the Biovector" nanoparticles were retained on the nasal turbinates. These findings were confirmed by whole body autoradiography. In a further study, the excretion balance was evaluated after intranasal and intravenous administration of radiolabelled Biovector" to rats. This study confirmed that systemic absorption is very low after intranasal administration, while after intravenous administration the elimination of the radioactive dose was slow and most radioactivity was excreted via the kidneys in the urine. The long residence time in the nasal turbinates and low systemic absorption constitute a favourable pharmacokinetic profile for administration to the nasal mucosae. The local tolerance and mutagenicity results indicate a good safety profile for the Biovector" nanoparticles.
IP2D9S!
TOXICOLOGICAL STUDIES ON THE PHARMACEUTICAL EXCIPIENT AQUATERIC® AQUEOUS ENTERIC COATING
L.A. Kotkoskie *, K.J. Batt, C. Freeman, M.A. Palmieri. FMC Corporation, Princeton, NJ. USA Aquateric Aqueous Enteric Coating is a water-based, reconstituted dispersion of cellulose acetate phthalate latex which functions as an enteric film coating for pharmaceuticals and solid dietary supplements. A subchronic toxicity study, developmental toxicity study, and genotoxicity battery were conducted using FDNOECD guidelines in order to verify the safety of this material. The results showed that Aquateric was not mutagenic in five tester strains of S. typhimurium in the presence or absence of metabolic activation in the Ames test. Negative results were obtained in the mouse lymphoma forward mutation assay both with and without metabolic activation. There was no significant increase in the frequency of mouse bone marrow micronucleated polychromatic erythrocytes following a single oral dose of 5000 mglkg Aquateric. The results of a subchronic toxicity study conducted in Sprague-Dawley rats (20/sexlgroup) fed Aquateric in diet for 90 days at levels of 0 (control), 5000, 25,000 or 50,000 ppm indicated no adverse toxicological effects. Aquateric showed no evidence of maternal or developmental toxicity when tested in a developmental toxicity study in Sprague-Dawley rats (25/group) at levels of 0 (control), 5000, 25,000 or 50,000 ppm in diet from gestational days 6 through 15. The results of these studies demonstrate that Aquateric does not exhibit genotoxicity, developmental toxicity or target organ toxicity. These results and the existing toxicological database on the components of Aquateric support the safety of Aquateric for use in pharmaceutical and dietary supplement applications.
117
IP2D96 I OF A NEW GENOMIC APPROACH TO MONITOR TOXICITY CANDIDATE COMPOUNDS FORDEVELOPMENT Schweighoffer. BioScreen Therapeuti cs SA, 58 boule vard Saint Den is, 92400 Courbevoie, France BST (BioScreen Therapeutics) has developped a new genomic technology, DATAS"'. Among other applications, DATAS'" analyzes differentially expressed genes and provides: - readouts to improve drug efficacy - informations on the toxic profile of a compound. Treatment of tissues or of cell cultures with a chemical induces changes in gene expression which reflect the specific properties of the com~und. Toxic agents will elicit specific genomic programs. DATAS identifies these toxic signatures. These genomic markers constitute DATAS'· Banks which are cDNA libraries representative of the genomic program initiated by a given class of toxic compound. T Hybridization of the DATAS • Banks can be then realized with probes derived from mRNA samples extracted from tissues or cell cultures treated by a candidate drug. The hybridization pattern provides clues to address the ability of this drug to engage a genomic program which is, at least partially, a landmark of genomic changes that occur upon treatment with toxic compound s. This approach constitutes therefore a shortcut to select compounds which are suitable for further pharmaceutical development. Results on the feasibility of DATAS'" are presented and provide new insights on the relationship between toxicity and apoptosis.
IP2D97 I
EFFECTOF POTENTIAL ANTIOXIDANTS ON MODEL OF CHRONIC COLITISIN RATS
V. ~retinova *, V. Grossmann . Institut e ofExperimental Biopharmaceutics, Joint laboratories ofPRO.MED.CS Praha a.s. and the Czech Academy of Sciences, Hradec Krdlove, Czech Republic Alternative to trinitrobenzensulfonic acid (TNBS) the dinitrobenzensulfonic acid (DNBS), readily available in suitable pharmaceutical forms, was used to induce immunogeni c rat model of chronic colitis. Our present study confirms that intracolonic instillation of TNBS and DNBS (20 mg per animal) in 50% etanol produced comparable severity of colonic injury. according to used criteria: body weight gain, presence or absence of diarrhea, adhesions and obstructions, wet colon weight, percentage of water in the colon (measured as a difference between wet and dry weight of the colon sample) and the macroscopic score of the colon damage. We have tried to influence the DNBS-induced colitis by pretreatment of animals with o-tocoferol. /I-caroten, 6-hydroxynicotinic acid and selenium in a dose 50 mglkg, except for selenium where a dose of 2.5 mglkg was used. Tested drugs were administered i.p. 30 min before DNBS, 6 h after DNBS and daily for 5 days. Control groups received appropriate vehiculurn, Rats were killed 24 h and 7 days after instillation of DNBS. Pretreatment with tested drugs showed that the o-tocoferol reduced all followed criteria in 7 days significantly. In this case, the water content in the and the macroscopic score was reduced colon was significantly decreased , already after 24 h. Other tested drugs had no effect.
IP2D9S1
CARCINOGENESIS OF EBROTIDINE IN RAT
A. Romero *, T. Grau, F. Villamayor. Centro de Investigacion Grupo Ferrer, Barcelona, Spain Ebrotidine (a novel H2 antagonist) has been administered at the doses of 50, 200 ( ISO), 300 and 500 mglkg to4 groups of rats (50 males and 50 female each) for 24 months by oral route. Two concurrent control groups (50 males and 50 female each) were included. Test substance was mixed with the diet. The study design as well as the statistical methodology followed the Guidelines for this type of studies and
IP2D94 I
N
PRECLINICAL TOXICOLOGY OF BIOVECTOR NANOPARTlCLES: PART II, LOCAL TOLERANCE, GENETIC TOXICOLOGY ANDPHARMACOKINETICS
R. Kravtzoff *, T. Appelqvist, H. Haddouk, X. Manciaux, G. Cholet, 1. De Miguel, M. Major, D. Betbeder, R. Forster. Biovector Therapeutics, BP 169,31676 Labege; crr Centre International de Toxicologie, BP 563, Miser ey. 27005 Evreux, France Biovector" nanoparticles are a family of cross-linked polysaccharide nanoparticles surrounded by a lipid layer, developed as a vehicle for drug delivery. The local tolerance, genetic toxicology and pharmacokinetics of a cationic Biovector" with high charge density have been evaluated prior to human healthy volunteer studies by the intranasal route. The local tolerance was studied following twice daily intranasal administration to New Zealand rabbits over a period of seven days. The local tolerance was good and there were no treatment-related clinical or histopathology findings. The potential mutagenicity of Biovector" nanoparticles was studied in the Ames test and the mouse micronucleus test: negative results were obtained in both studies. The plasma kinetics and tissue distribution of radiolabelled Biovector" nanoparticles was studied after intranasal administration to rats. Systemic absorption was low, and the Biovector" nanoparticles were retained on the nasal turbinates. These findings were confirmed by whole body autoradiography. In a further study, the excretion balance was evaluated after intranasal and intravenous administration of radiolabelled Biovector" to rats. This study confirmed that systemic absorption is very low after intranasal administration, while after intravenous administration the elimination of the radioactive dose was slow and most radioactivity was excreted via the kidneys in the urine. The long residence time in the nasal turbinates and low systemic absorption constitute a favourable pharmacokinetic profile for administration to the nasal mucosae. The local tolerance and mutagenicity results indicate a good safety profile for the Biovector" nanoparticles.
IP2D9S!
TOXICOLOGICAL STUDIES ON THE PHARMACEUTICAL EXCIPIENT AQUATERIC® AQUEOUS ENTERIC COATING
L.A. Kotkoskie *, K.J. Batt, C. Freeman, M.A. Palmieri. FMC Corporation, Princeton, NJ. USA Aquateric Aqueous Enteric Coating is a water-based, reconstituted dispersion of cellulose acetate phthalate latex which functions as an enteric film coating for pharmaceuticals and solid dietary supplements. A subchronic toxicity study, developmental toxicity study, and genotoxicity battery were conducted using FDNOECD guidelines in order to verify the safety of this material. The results showed that Aquateric was not mutagenic in five tester strains of S. typhimurium in the presence or absence of metabolic activation in the Ames test. Negative results were obtained in the mouse lymphoma forward mutation assay both with and without metabolic activation. There was no significant increase in the frequency of mouse bone marrow micronucleated polychromatic erythrocytes following a single oral dose of 5000 mglkg Aquateric. The results of a subchronic toxicity study conducted in Sprague-Dawley rats (20/sexlgroup) fed Aquateric in diet for 90 days at levels of 0 (control), 5000, 25,000 or 50,000 ppm indicated no adverse toxicological effects. Aquateric showed no evidence of maternal or developmental toxicity when tested in a developmental toxicity study in Sprague-Dawley rats (25/group) at levels of 0 (control), 5000, 25,000 or 50,000 ppm in diet from gestational days 6 through 15. The results of these studies demonstrate that Aquateric does not exhibit genotoxicity, developmental toxicity or target organ toxicity. These results and the existing toxicological database on the components of Aquateric support the safety of Aquateric for use in pharmaceutical and dietary supplement applications.
117
IP2D96 I OF A NEW GENOMIC APPROACH TO MONITOR TOXICITY CANDIDATE COMPOUNDS FORDEVELOPMENT Schweighoffer. BioScreen Therapeuti cs SA, 58 boule vard Saint Den is, 92400 Courbevoie, France BST (BioScreen Therapeutics) has developped a new genomic technology, DATAS"'. Among other applications, DATAS'" analyzes differentially expressed genes and provides: - readouts to improve drug efficacy - informations on the toxic profile of a compound. Treatment of tissues or of cell cultures with a chemical induces changes in gene expression which reflect the specific properties of the com~und. Toxic agents will elicit specific genomic programs. DATAS identifies these toxic signatures. These genomic markers constitute DATAS'· Banks which are cDNA libraries representative of the genomic program initiated by a given class of toxic compound. T Hybridization of the DATAS • Banks can be then realized with probes derived from mRNA samples extracted from tissues or cell cultures treated by a candidate drug. The hybridization pattern provides clues to address the ability of this drug to engage a genomic program which is, at least partially, a landmark of genomic changes that occur upon treatment with toxic compound s. This approach constitutes therefore a shortcut to select compounds which are suitable for further pharmaceutical development. Results on the feasibility of DATAS'" are presented and provide new insights on the relationship between toxicity and apoptosis.
IP2D97 I
EFFECTOF POTENTIAL ANTIOXIDANTS ON MODEL OF CHRONIC COLITISIN RATS
V. ~retinova *, V. Grossmann . Institut e ofExperimental Biopharmaceutics, Joint laboratories ofPRO.MED.CS Praha a.s. and the Czech Academy of Sciences, Hradec Krdlove, Czech Republic Alternative to trinitrobenzensulfonic acid (TNBS) the dinitrobenzensulfonic acid (DNBS), readily available in suitable pharmaceutical forms, was used to induce immunogeni c rat model of chronic colitis. Our present study confirms that intracolonic instillation of TNBS and DNBS (20 mg per animal) in 50% etanol produced comparable severity of colonic injury. according to used criteria: body weight gain, presence or absence of diarrhea, adhesions and obstructions, wet colon weight, percentage of water in the colon (measured as a difference between wet and dry weight of the colon sample) and the macroscopic score of the colon damage. We have tried to influence the DNBS-induced colitis by pretreatment of animals with o-tocoferol. /I-caroten, 6-hydroxynicotinic acid and selenium in a dose 50 mglkg, except for selenium where a dose of 2.5 mglkg was used. Tested drugs were administered i.p. 30 min before DNBS, 6 h after DNBS and daily for 5 days. Control groups received appropriate vehiculurn, Rats were killed 24 h and 7 days after instillation of DNBS. Pretreatment with tested drugs showed that the o-tocoferol reduced all followed criteria in 7 days significantly. In this case, the water content in the and the macroscopic score was reduced colon was significantly decreased , already after 24 h. Other tested drugs had no effect.
IP2D9S1
CARCINOGENESIS OF EBROTIDINE IN RAT
A. Romero *, T. Grau, F. Villamayor. Centro de Investigacion Grupo Ferrer, Barcelona, Spain Ebrotidine (a novel H2 antagonist) has been administered at the doses of 50, 200 ( ISO), 300 and 500 mglkg to4 groups of rats (50 males and 50 female each) for 24 months by oral route. Two concurrent control groups (50 males and 50 female each) were included. Test substance was mixed with the diet. The study design as well as the statistical methodology followed the Guidelines for this type of studies and