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SRpT C 0 V A-N-CE.' THE DEVELOPMENT SERVICES COMPANY L5178Y TK FINAL REPORT MOUSE LYMPHOMA FORWARD MUTATION WITH A CONFIRMATORY ASSAY WITH N-ETFOSE T-6316 ASSAY AUTHOR - Maria A. Cifone,PhD PERFORMING LABORATORY Covance LaboratoriesInc(Covance) 9200 Leesburg Pike Vienna,Virginia22182 LABORATORY PROJECT IDENTIFICATION Covance Study No.: 20785-0-431 ICH 3M Study No.: T-6316.12 SUBMITTED TO 3M CorporateToxicology 3M Center Building220-2E-02 St.Paul,Minnesota 55133-3220 STUDY COMPLETION DATE September 05, 2000 1 of 29 Covance20785-0-43I1CH 3M StudyNo.:T-6316-12 QUALITY ASSURANCE STATEMENT L5178Y TK +/-Mouse Lymphoma Forward Mutation Assay with a ConfirmatoryAssay withN-ETFOSE T-6316 The reporthas been reviewed by the QualityAssurance Unit of Covance LaboratoriesInc.,in accordancewith the Good Laboratory Practiceregulationsas setforthintheFood and Drug Administration(FDA) Title21 of theU.S.Code of FederalRegulationsPart58,and with any applicableamendments. The followinginspectionswere conducted and the findingsreportedto the Study Directorand studydirectormanagement. Writtenstatusreportsof inspectionsand findingsareissuedto Covance management accordingtostandardoperatingprocedures. InspectionDates May 31, 2000 July 19-20,2000 August 30, 2000 Phase Scoring DraftReport Review FinalReport Review Dates Reported to Study Directorand Study DirectorManagement May 31, 2000 July 20, 2000 August 30,2000 Auditor S.Ballinger P. Cdceres P. Cdceres -::@ cl@ RepresentatiQveu,aliAtsysuranUcneit 0,/ S-/(:)o Date -2- STUDY COMPLIANCE Covance20785-0-43I1CH 3M StudyNo.: T-6316.12 AND CERTIFICATION The studywas conductedincompliancweiththeGood LaboratorPyracticreegulatioanssset forthin theFood and Drug Administration(FDA) Title21 of theU.S.Code of Federal RegulationsPart58, and with any applicableamendments. There were no deviationsfrom the regulationsor the signed protocolthatwould affectthe integritoyf the studyor the interpretation of thetestresults.The raw datahave been reviewed by the Study Director,who certifietshatthe evaluationof the testarticlaes presentedhereinrepresentsan appropn*ateconclusionwithinthe contextof the studydesign and evaluationcriteriaA.ll testand controlresultsin thisreportare supportedby an experimentaldata recordand thisrecordhas been reviewed by the Study Director. Study Director: N@4 A. Cifone,PhD Date Genetic and Molecular Toxicology -3- Covance20785-0-43I1CH 3M StudyNo.:T-6316.12 TA,BLE OF CONTENTS PageNo. ABSTRACT .........................................................................5................ STUDY INFORMATION .............................................................6................ Sponsor Test Article Assay Information Study Dates SupervisoryPersonnel OBJECTIVE ........................................................................6................ TEST SYSTEM RATIONALE ........................................................7................ MATERIALS AND METHODS .......................................................7................ Test System TestArticle ControlArticles S9 Metabolic ActivationSystem Dose RangefindingAssay Mouse Lymphoma MutagenicityAssay DATA .............................................................................1.2............... Data Presentation Assay Acceptance Criteria Assay EvaluationCriteria RESULTS ..........................................................................1.5............... Test ArticleHandling Dose Rangefinding Assay Mutation Assays CONCLUSION ....................................................................1.7................ RECORDS TO BE MAINTAINED ...................................................1.7................ REFERENCES .....................................................................17................ DATA TABLES ....................................................................18................ HISTORICAL CONTROL DATA ....................................................2.9................ -4- Covance 20785-0-43I1CH 3M StudyNo.:T-6316.12 ABSTRACT The objectivoefthisinvitraossaywas toevaluatteheabilitoyfthetestarticlNe-,ETFOSE T-6316, toinduceforward mutationsatthethymidinekinase(TK) locusin themouse lymphoma L5178Y cellline.The testarticlweas solublein thevehicle(dimethylsulfoxidDeM,SO) at 125 mg/mL, the highestconcentrationprepared. A dose rangefindingassaywas performed with and withoutmetabolicactivatiounsinga treatmentperiodof approximately4 hours. In addition,a dose rangefindingassaywithout metabolicactivatiounsinga treatmentperiodof approximately24 hourswas performed. The dose rangefindingassayswere initiatewdith concentrationsfrom 2.47 to 1250 @ig/mL. Inthe presenceand absence of ratliverS9 metabolicactivitwyith a 4-hourtreatmentperiod, N-ETFOSE T-6316 was noncytotoxicup to 19.7 gg/mL. Moderate cytotoxicitwyas induced from 39.3to 157 @ig/mL and higher concentrationswere excessivelycytotoxicor lethal.In the nonactivationdose rangefindingassayusinga 24-hour treatmentperiod,the testarticlienduced no cytotoxicitayt2.47 )ig/mL,weak cytotoxicitayt4.93gg/mL, and moderatelyhigh cytotoxicitayt9.85 @ig/mL. Higher concentrationswere excessivelycytotoxicor lethal.Dose levelsforthe mutation assayswere based on theseresults. In thenonactivationmutation assaywith a treatmentperiodof approximately4 hours,sixdoses rangingfrom 25.3 to 201 gg/mL were analyzed formutant inductionand weak cytotoxicittyo high cytotoxicitwyas induced. None of the analyzed treatmentsinduced a mutant frequencythat exceeded the minimum criterifaor a positiveresponse.A confirmatoryassaywas perfon-ned. In theconfirmatorynonactivationmutationassay,which was performed with a 24-hour treatmentperiod,seven treatmentsfrom 1.25 to 15.0 @tg/mL were analyzed and no cytotoxicittyo high cytotoxicitwyas induced. None of thetreatmentsinduced a mutant frequencythat exceeded the minimum criterifaor a positiveresponse. The testarticlweas, thereforee,valuated as negativewithoutmetabolicactivation. In the initiamlutation assay inthe presenceof S9 metabolicactivationf,ourtreatmentsfrom 25.3 to 101 gg/mL were analyzedand weak cytotoxicittyo very high cytotoxicitwyas induced. None ofthe analyzed treatmentsin eitherassay induced a mutant frequency thatexceeded the minimum criterifaora positiveresponse.A confirmatorymutation assaywas perfon-ned. Inthe confirmatoryactivationmutation assay,eighttreatmentsfi7om20.0 to 150 gg/mL were analyzedand weak cytotoxicittyohigh cytotoxicitwyas induced. None of thetreatments induced a mutant frequencythatexceeded the minimum criterifaora positiveresponse.The test articlweas, thereforee,valuatedas negativewith metabolicactivation. The testarticleN,-ETFOSE T-6316, was evaluatedas negativeforinducingforward mutationsat theTK locusin L5178Y mouse lymphoma cellsunder activationand nonactivation. -5- STUDY INFORMATION Covance 20785-0-43I1CH 3M StudyNo.:T-6316-12 Sponsor 3M CorporatTeoxicology TestArticle SponsorIdentificatiNo-nE:TFOSE T-6316 Lot 30035, 30037, 30039 Purity98.1% (August 19 sample) TM #: 1084A3 (August 19 sample) Dates Received: August 19, 1999 and June 07, 2000 Physical Description: whiteto beigesolid(August 19 sample) beigechunky solid(June07 sample) Storage Conditions: room temperature Assay Information Type of Assay: L5178Y TK+/-Mouse LyTnphoma With A ConfirmatoryAssay ProtocolNo.: 431 ICH Edition2 Covance Study No.: 20785-0-431 ICH Forward Mutation Assay Study Dates InitiationDate: May 08,2000 Experimental StartDate: May 10,2000 Experimental Termination Date: June 22,2000 Supervisory Personnel Study Director: Maria A. Cifone,PhD Laboratory Supervisor: Kathryn Flanders,MS OBJECTIVE The objectiveof thisstudywas to evaluatetheabilitoyf thetestarticlteoinduce forward mutationsatthethymidinekinase(TK) locusof L5178Y mouse lymphoma cellsasassayedby colony growth inthepresenceof 5-trifluorothymidi(nTeFT). The assaydesignisbased on OECD Guideline476, updated and adopted July21, 1997,and the ICH S2B Guideline, "Genotoxicity:StandardBatteryforGenotoxicityTestingof Pharmaceuticals". -6- Covance 20785-0-43I1CH 3M StudyNo.:T-6316.12 TEST SYSTEM RATIONALE Thyinidinkeinase(TK)isanenzyme thatallowscelltsosalvagtehymidinferomtheculture medium forDNA synthesis.IfthethyrnidineanalogTFT isincludedinthegrowth medium, the analogwillbe phosphorylatedviatheTK pathway and willcausecelldeathby inhibitinDgNA synthesis.Cellswhich areheterozygousattheTK locus(TK+'-)may undergo a single-step forward mutation tothe TK-/-genotype inwhich littloerno TK activitryemains. Such mutants areviableinnormal culturemedium because de novo DNA synthesisdoes not requireexogenous thyrnidine.TK-/-mutants,however, are resistanttoTFT because they cannot incorporatethis toxicanalog ofthyrnidineintoDNA. Cellswhich grow to form coloniesinthepresenceof TFT arethereforeassumed tohave mutated, eitherspontaneouslyor induced by the testarticlea,tthe TK-1-locus. MATERIALS AND METHODS Test System Test Cells. The mouse lymphoma L5178Y cellline,heterozygous atthe TK locus and designatedas clone3.7.2C,was used forthisassay. Stock cultureswere obtainedfrom Dr. Donald Cliveand arestoredin liquidnitrogen.Laboratory culturesforthemutation assays were maintainedin logarithmicgrowth by serialsubculturingforup to4 months and were then replacedby cellsfrom the frozenstock. Cultureswere grown in a shakerincubatorat approximately37'C. A continuouscelllogwas kept to recordgrowth,doublingtimes,and subcultureoperations.To reduce the frequencyof spontaneous TK-/-mutants priorto use inthe mutation assay,cellcultureswere exposed to conditionsthatselectedagainsttheTK-/-phenotype and then returnedtonormal growth medium for3 to 8 days. Media and Cell Culture Conditions. The medium used forthisstudywas RPMI 1640 (Amacher etal.,1980;Cliveetal.,1987) supplemented with horse serum (10% by volume), PluronicoF68, L-glutamine,sodium pyruvate,penicilliannd streptomycin.Treatment medium was Fischer'smedium with the same medium supplements used inthe culturemedium except thatthehorse serum concentrationwas reduced to 5% by volume. Cloning medium consistedof the R-PMI 1640 culturemedium with up to 20% horseserum, withoutPluronicoF68 and with the additionof 0.24% BBL(& agarto achieve a semisolidstate.Selectionmedium was cloning medium thatcontained3 @ig/mLof TFT (Cliveetal.,1987). Test for Mycoplasma Contamination. Mycoplasma testingwas performed by a commercial laboratoryon stockculturespriortopreparingstocksforfreezing.Stock culturesforthe mutation assayswere maintained up to4 months afterthawing a sample from a frozenstock. Mycoplasma testingwas alsoperformed on culturesthawed foruse inassayspriorto discarding thestock.This ven*fiedthattherewere no mycoplasma during thelifeof theculture.Both direct culturingmethods and the indirectHoechst stainingmethod were used. -7- Covance20785-0-43I1CH 3M StudyNo.: T-6316.12 KaryotypeStabilityK.aryotypestabiliatsym,easuredby mean chromosomalnumber,was routinelyperfon-nedon stockculturesused forassays.Mean chromosomal number was determined priorto discardingthe stockto ensurethatchanges inthe culturehad not occurred. Karyotype analysis,includingbanding, was performed on cellsafterpreparationof a freshftozen stock culture. Test Article The sponsor was responsibleforthe determinationof the testarticlestabilitaynd the testarticle characteristicas definedin the GLP regulations. Control Articles Vehicle Control Article.The vehicleof choiceforthe testarticlweas DMSO (Sigma Chemical Co., Lot No. 99HOO20, CAS #67-68-5). Concurrentvehiclecontrolswere performed foreach portionofthe assayby exposing thecellstoDMSO inculturemedium. Intheactivatiopnortion of the assays,the vehiclecontrolswere alsoexposed tothe S9 metabolic activatiomnix. Single vehiclecontrolcultureswere initiateidn thedose rangefindingassays and threevehiclecontrol cultureswere initiateidn themutation assays. PositiveControl Articles.The positivecontrolarticlelsistedbelow were chosen because of the largedatabase availableand because both chemicalsinduce small and largecolonies(Clive etal.,1987,Young etal.,199 1). Methyl methanesulfonate(MMS) isa directactingmutagen thatishighlymutagenic to L5178Y TK+@-cells.MMS (AldrichChemical Co.,Lot No. 08109BU, CAS # 66 27-3)was used in duplicateat 13 @tg/niJf-orthe nonactivationassay with a 4-hour treatmentperiod,and in duplicateata concentrationof 6.5 ptg/mL forthe nonactivationassaywith a 24-hour treatment period. Methylcholanthrene(MCA) requiresmetabolicactivatiobny microsomal enzymes to become mutagenic to L5178Y TK+/-cells.MCA (Sigma Chemical Co.,Lot No. 77H2515, CAS # 56-49-5)was used at2 @ig/mL and 4 @tg/mL as a positivecontrolforassaysperformed with S9 metabolicactivation. S9 Metabolic Activation System The invitrometabolicactivatiosnystem was comprised of ratliverenzymes (S9 fractiona)nd an energyproducing system (CORE) comprised of nicotinamideadenine dinucleotidpehosphate (NADP, sodium salt)and isocitrateT.he S9 enzymes were preparedcommercially(Molecular Toxicology,Inc.,Boone, NC) and were testedforsterilitaynd enzyme activityT.he enzymes were obtainedfrom the9000 x g supernatant(S9)of liverhomogenate from male Sprague Dawley ratstreatedwith Aroclor 1254,which inducesmixed functionoxidaseenzymes capable of transformingchemicalstomore activeforms. Rats were treatedonce with 500 mg/kg of Aroclor 1254,and the S9 was prepared approximately5 days later.The S9 and reactionmixture (CORE) were retainedfrozenatabout -80'C untilused. -8- Covance20785-0-43I1CH 3M StudyNo.: T-6316.12 S9 MetabolicActivatioSnystem Component FinalConcentrationin Cultures -NADP (sodiumsalt) 3 mM Isocitrate 15 mM S9 homogenate -10 @tL/mL Dose Rangefinding Assay A preliminarydose rangefindingcytotoxicityexperiment was performed with a treatmentperiod of approximately4 hours with and withoutS9 activations,incesubstantiaslhiftsintoxicityoften occur forthetwo testconditions.In addition,a nonactivationassaywith a treatmentperiodof approximately24 hours was performed. A wide range of testarticlceoncentrationswas tested forcytotoxicitsytartinagt 1250 @ig/mL,and followedby nine lower concentrationsprepared in 2-folddilutionsteps.Afteran exposuretime of approximately4 hours or approximately 24 hours at35-38'C in an orbitalshakerat80 10 orbitsper minute,the cellswere washed twice with culturemedium and resuspendedin culturemedium. The cellsreceivingthe24-hour treatmentwere counted and subcultured,as necessary.Following theterminationof the treatmentperiods,the cellswere incubatedovernightusingproceduresidenticatlo thosefor mutation experiments.A cellcountwas determinedafterthe growth periodtomeasure the reductionincellgrowth relativteo theconcurrentvehiclecontrolcellcultures.The preliminary dose rangefindinginformationwas then used to selectdose levelsforthe mutation assay. Test articleconcentrationsare chosen to cover a toxicityrange from 10% to 20% survivaltono apparen- teffecton growth compared tothevehiclecontrol.Iflittloer no toxicitiysobserved and solubilitiysmaintained,themutationexperiment isinitiatewdith a maximum concentrationof 5 mg/mL or 10 mM (which everislowest).Ifprecipitatioonf thetestarticloeccursin the culturemedium, themaximum applieddose isatleasttwicethe solubilitlyimitin culture medium. In thisassay,thehigh dose limitedby cytotoxicity. Mouse Lymphoma Mutagenicity Assay The assayprocedureused was based on thatreportedby Clive and Spector (1975),Cliveetal. (1979),Amacher etal.(1980)and Cliveetal.(1987). Although tenor elevendoseswere selectedto initiataemutation experiment,the objectivewas to carryatleastfourdoses through theentireassay.This procedurecompensated fornormal variationisn cellulatroxicityand helped toensure thechoice of atleastfourdoses over a wide cytotoxicitryange. InitialNonactivation Assay. Logarithmicallygrowing laboratorystockcultureswere seeded intoa seriesof tubesat6 x 106 cellspertube. The cellswere pelletedby centrifugationt,he culturemedium removed, and the cellsresuspended to a finalvolume of 10 mL of treatment medium. The tubeswere placedin an orbitalshaker incubatorat35-38'C and rotatedat 80 10 orbitsperminute. Afteran exposure periodof approximately4 hours,thecellswere -9- Covance 20785-0-43I1CH 3M StudyNo.: T-6316.12 centrifugaenddthetreatmenmtedium removed.The cellwserethenwashed,resuspendeidn 20 mL of culturemedium and returnedto theorbitalshakerincubator. The assayconditionsconsistedof vehiclecontrolsintriplicattew,o positivecontrolsand eleven differentestarticledose levelsusingone cultureper dose level.Treatedculturesmay be eliminatedduring the expressionperiodas long as fourdose levelsare leftforanalysisofmutant induction. The appearance of the treatedcultureswas recordedboth atthetime of treatmentand afterthe treatmentperiod. When thepH indicatorinthemedium had a colorchange, thepH was measured usingpH indicatorstrips. A standardexpressionperiodof 2 days was used to allow formutant recovery,growth and expressionof the TK-/-phenotype. Celldensitieswere determinedon Day I and were adjustedto 3 x 105 cells/mL in 20 mL of growth medium. Ifthecellsina culturefailedtomultiplyto a 105 densityof 4 x cells/mL on the firsdtay aftertreatment,the culturewas not subcultured.On Day 2,cellcounts were againdetermined,and appropriatecultureswere selectedforcloningand mutant selection. Six doses were selectedformutant analysis.Ifpossible,doses were selectedto includenontoxic to highlytoxictreatmentconditions.Although relativgerowth givesan indicatioonf whether a testarticlieshighlyor weakly cytotoxics,pecificrangesforweak, moderate,highlytoxicand excessivelytoxicarenot specified.Severalfactorsgo intothecalculationand theStudy Director makes a decisionconcerningthelevelof cytotoxicittyhathas occurred.Cultureswith cell densitieslessthan approximately3 x 105 cells/mLwere not consideredforselection. A totalof 3 x 106 cellsfrom each selectedtubewas suspended in selectionmedium in softagar torecoverTFT-resistantmutants. This sample was distributeidntothree100 mm dishes.The absoluteselectioncloningefficiencywas determinedby seedingthreedisheswith a totalof approximately600 cellsin agar cloningmedium. All disheswere placed inan incubatorat35- 38'C with 4-61/@C02:95% humidifiedair.After 13 days intheincubator,thecolonieswere countedwith theLoatsAssociates,Inc.(LAI) High ResolutionColony Counter(HRCC) System forthe Mouse Lymphoma Assay, Version 1.05bO4c. The mutant frequency was calculatedas the ratioof the totalnumber of mutant coloniesfound in each setof threemutant selectiondishesto the totalnumber of cellsseeded,adjustedby the absoluteselectioncloningefficiency.Ifone dishin eithersetwas lostdue tocontaminationor othercause,the colony count of the missing dishwas determinedby a proportionequationbased upon the weights of the threedishesof the setand the colony countsin the two acceptable dishes.Ifa lostplatewas not availableforweighing,thecolony count of thelostplatewas determined from the average of the two remaining acceptableplates. The measurement of the cytotoxicitoyf each treatmentwas the relativesuspensiongrowth of the cellsover the2-day expressionperiod(forthe4-hourtreatment)or therelativseuspension growth over the3-day treatmentand expressio-nperiod(forthe24-hour treatment)multipliedby 10- Covance20785-0-43I1CH 3M StudyNo.:T-6316.12 therelaticvleoningefficienactythetimeofselectioAnl.thoughnotstrictalmyeasureofcell sur-vivatlh,isparameter(calledrelativgerowth or relativteotalgrowth,RTG) providesa measure of the effectivenesosf treatmentand was used as the basisforselectingdoses forany necessary subsequent trials. Conf-irmatory Nonactivation Assay. The confirmatoryassayprocedure was similartothe assay using a treatmentperiodof approximately4 hours exceptthattheexposure time was increasedto approximately24 hours. The assay was conducted using resultsfrom the dose rangefindingassaywith a treatmentperiodof approximately24 hours. Ten treatmentswere initiateda,nd seven were analyzed formutant induction. The cellswere obtainedfrom logarithmicallgyrowing laboratorystockculturesand were seeded intoa seriesof tubes at6 x 106 cellsper tube. The cellswere pelletedby centrifugationt,he culturemedium removed, and the cellsresuspended in a finalvolume of 20 mL of treatment medium. The dosed tubeswere closed,vortexed and placedin an orbitalshakerincubatorat3538'C at80 10 orbitsper minute. Aftera treatmentperiodof approximately24 hours,thecells were centrifugedand the treatmentmedium removed. The cellswere thenwashed, and resuspendedin 20 mL of growth medium at3 x 105 cellsper mL. The cultureswere then returnedtothe orbitalshaker. A standardexpressionperiodof 2 days followingterminationof treatmentwas used to allow recovery,growth and expressionofthe TK-/-phenotype. Celldensitieswere determinedthe day aftertreatmenttermination,and each culturewas adjustedto3 x 105 cells/mLin 20 mL of growth medium. Ifthecellsina culturefailedtomultiplyto a densityof 4 x 105/mL on thefirst day aftertreatmenttermination,the culturewas returnedtothe incubatorwithoutbeing subcultured.The next day cellcounts againwere determined,and appropriatecultureswere selectedforcloningand mutant selection.Cultureswere counted 12 days aftercloning. InitialActivationAssay. The activationassaywas identicatlo the nonactivationassayexcept fortheadditionof theS9 fractionofratliverhomogenate and necessarycofactors(CORE) duringthetreatmentperiodof approximately4 hours. The treatmentmedium includedthisS9 activatiomnix, which was preparedinunediatelypriortouse and kept chilled.Each batchof S9 was testedforactivatioonf theMCA positivecontrolarticlbeeforeitwas used forthe mutagenicityassay.The S9 homogenate was commercially prepared(MolecularToxicology, Inc.,Boone, N.C.,Lot No. 955) and consistedof the 9000 x g supernatantfrom the homogenized liversof Aroclor 1254-inducedadultmale Sprague Dawley rats.Cultureswere counted 13 days aftercloning.Eleven treatmentswere initiateda,nd fourwere cloned formutant analysis. Confirmatorv ActivationAssay. The proceduresused in theconfirmatoryactivatioanssay were identicatlo theinitiaalctivatioanssay.Eleven treatmentswere initiateadn,d eightwere cloned formutant analysis.Cultureswere counted 13 days aftercloning. SizingAnalysis. The L5178Y TK +/-mutation assay produces a bimodal distributioonf largeand smallmutant colonies.The originof thebimodal distributioonf mutant colonysizesis -11- Covance 20785-0-43I1CH 3M StudyNo.: T-6316.12 consideretdoreflectthetypesofgenetidcamage,withthelargecoloniedserivedfromcellwsith intragenicmutations thataffectonly theTK gene and the smallcoloniestheresultof larger mutationsthataffectcellgrowth as well asthe TK gene (Hozier etal.,1985). Both thesmalland largecolonieswere quantifiedforallcultures.A bimodal curve isgenerated and small and largecoloniesare quantitatedby the areasunder the curves. The largecolonies presumably an'sefrom pointmutationsand the smallcoloniesfrom chromosome changes. The LAI Automated Colony Counter was used. This countersizesallanalyzedcultures. DATA Data Presentation The historicaclontroldataarepresentedafterthedatatables.This reportincludesthefollowing information: Dose Rangefluding Data. These dataincluded,foreach treatmentconditiont,hedailycell densitiesofthe individualculturesand the celldensitiesrelativetothe vehiclecontrols. Cell Growth Characteristics.This includedthe number of cellsseeded forthe analysisof mutant frequencies,the phenotypic expressiontime, and the selectiveagentand concentration. In additiond,ailycelldensitieisntheindividualculturescarriedthroughtheexpressionperiod and cloningwere included.The suspensiongrowth forvehicleand positivecontrolsf,orthe 4-hourtreatmentstudiescalculatedas (Day I celldensity/3x 105) X (Day 2 celldensity/3x 105 or Day I densityifnot splitback) describesthegrowth of the controlculturesduringthe expressionperiod.For thenonactivationassaywith a 24-hour treatmentperiod,the suspension growth forvehicleand positivecontrolsc,alculatedas [Treatmenttermination(Day 1)cell density/3x 10']x [Day 2 celldensity/3x 05 1 or Day I densityifnot splitback] x [Day 3 cell density/3x 105 or Day 2 densityifnot splitback],describesthe growth of the controlcultures duringthe expressionperiod.For the test-artictlreeatedcultures,therelativesuspensiongrowths were includedand calculatedas above, and were expressed as percentagesof the average vehicle controlsuspensiongrowth. The relativceloningefficiencieosf testarticle-treatceudltureswere expressedaspercentagesof the average vehiclecontrolcloningefficiency.The expressionof RTG was theparameter thatwas used to assesstreatmentcytotoxicityand was obtainedby multiplyingtherelativesuspensiongrowth by the relativceloning efficiency/100. Mutant SelectionData. The mutant selectiondataincludesthe totalmutant colonies(i.et.otal number of mutant colony countsobtainedfrom 3 x 106 CellS sampled ftom one culture,seeded intoselectivmeedium and dividedamong threeculturedishes)and thetotalviablecolonies (i.et.hetotalnumber of colony countsobtainedfrom 600 cellssampled from one culture,seeded intononselectivemedium and dividedamong threeculturedishes).These were used tocalculate themutant frequencyforeach culture.The ratioof cellsseeded formutant selectiotno cells seeded forcloningefficiencywas 0.5 x 104 . Therefore,the mutant frequencywas: (totamlutant -12- Covance20785-0-43I1CH 3M StudyNo.:T-6316.12 4 colonies/totavliablecolonies)x 2 x 104. Mutant frequencywas given inunitsof 10-6. Also includedinthissectionwas the cloningefficiencyof vehicleand positivecontrolscalculatedas (totalnumber of viablecolonies/600x) 100%. Assay Acceptance Criteria An assaywas consideredacceptableforevaluationof thetestresultsonlyifallofthecriteria given below were satisfiedA.ctivationornonactivationassayswere repeatedindependently,as needed, to satisfyacceptancecriteriaT.he Study Directorreviewed each assayin accordance with the followingcriteria: Acceptable Controls. The averageabsolutecloningefficiencoyf thevehiclecontrolsshouldbe between 60% and 130%. A valuegreaterthan 100% ispossiblebecause oferrorsincellcounts (usually 10%) and variationisn celldivisionduringunavoidabledelaysbetween countingand cloningof many cultures. A minimum acceptablevalueforthe average suspensiongrowth of the vehiclecontrolsfor 2 days isan 8.0-foldincreaseover theoriginalcellconcentrations.Lower valuesrenderan assay unacceptablebecause of poor cellgrowth. The background mutant frequency(averageof vehiclecontrolvalues)iscalculatesdeparatelyfor concurrentactivationand nonactivationassays,even though the same populationof cellsisused foreach condition.For both conditions,the normal range of background frequenciesforassays performed with differenctellstocksis30 x 10-6 to 120 x 10-6 . Assays with backgrounds outside thisrange arenot necessarilyinvalidbut willbe evaluatedwith caution. At leastone of thepositivecontrolculturesineach trialshould induce a mutant frequencyof at least200 x 10-6 . A trialmay be acceptablewithouta positivecontrol(due tocontaminationor technicalerror)only ifthetestarticliespositive. Acceptable High Dose. For testarticlewsith weak or no mutagenic activitya,n assayshould includeappliedconcentrationsthatreduce the RTG to 10% or 20% of theaveragevehicle controlor reachthemaximum appliedconcentrationsgiven intheevaluationcriteriaR.TG representsa calculatioonf survivalthatisbased on both relativesuspensiongrowth duringthe expressionperiodand relativecloningefficiencyatthe time ofplating.Because mutant frequenciesincreaseas a functionof lethalitya,n attemptto obtaintreatmentsin therange of 10% to 20% RTG must be made inordertoconsiderthe assayas conclusive.This requirement was waived ifthe concentrationof the highestassayeddose was atleast75% of a higher, excessivelycytotoxicdose levelor ifthehighestdose was atleasttwicethesolubilitlyimitof the testarticlien culturemedium. There isno maximum toxicityrequirementfortestarticlewshich clearlyshow mutagenic activity. Acceptable Number of Doses. Mutant frequencywillbe consideredacceptableforevaluation only iftherelativecloningefficienciys 10% or greaterand thetotalnumber ofviableclones exceeds about60. These limitsavoidproblems with thestatisticdailstributioonf scorable coloniesamong dishes. -13- Covance20785-0-43I1CH 3M StudyNo.: T-6316.12 Mutantfrequenciefsoratleasftourdifferetnetstarticdloeselevelasrenon-naldleyten-niniend each assay;a minimum of four analyzed culturesisconsiderednecessaryto accepta singleassay forevaluationof the testarticle. Mutant frequenciesare normally derivedfrom setsof threedishesforboth mutant colony count and viablecolony count. In orderto allow forlossesdue tocontaminationor otherreasons,an acceptablemutant frequency can be calculatedfrom a minimum of two dishesper set. Assay Evaluation Criteria The testarticlewas evaluatedaspositive,negative,or equivocalinthisassay.A positive evaluationindicatesthatthe testarticliesa mutagen (inducesgene/chromosomal mutations)in thistestsystem. A negativeevaluationindicatesthetestarticliesno=utagenic inthistest system and causes no responsesthatcan be interpretedaspositive.However, thereare substancesforwhich theresultsremain questionable;any testarticlien thiscategorywillbe evaluatedas equivocal inthistestsystem. Evaluation of a PositiveResponse. The testarticliesevaluatedas positiveifdose-dependent increasesof 2-foldor greaterinmutant frequencyare obtainedover the concurrentbackground mutant frequency.The background mutant frequencyisdefinedas the averagemutant frequency of thevehiclecontrolcultures.The 2-foldor greaterincreaseisbased on extensiveexperience which indicatessuch responsesarerepeatablein additionaltrials.Itisdesirabletoobtainthis relationshifporatleastthreedoses,but thisgoaldepends on the dose stepschosen forthe assay and toxicityatwhich mutagenic activityappears. The dose-dependentrequirementiswaived ifa largeincreaseinmutant frequency(4-foldor higher)isobtainedfora singledose ator near thehighesttestabletoxicity.However, forthetest articlteobe evaluatedaspositive,any increasesmust be repeatableina second trial. Evaluation of a Negative Response. The testarticlweas evaluatedasnegativeifa 2-fold increaseinmutant frequencywas not observed for(1)a range of doses thatextendedtotoxicities causing 10% to20% RTG, or (2)forrelativelnyontoxictestarticlesa,range of doses extending tothemaximum concentratioonf 5 mg/mL or 10 mM (whicheverislower),or (3)a rangeof dosesthatextended toa levelapproximatelytwice thesolubilitlyimitin culturemedium, or (4)theincrease(sa)renot repeatablein a confirmatorytrial. Evaluationof an Equivocal Response. The testarticlweas evaluatedas equivocalin thistest system iftherewas no consistentevidence foreithera positiveor negativeevaluation. Other Considerations. Treatments with testarticletshatreduced the RTG tolessthan 10% may occurin an assay,buttheresultsobtainedatthishich toxicitywere consideredbiologically irrelevanatnd were not used to evaluatethe testarticle. For some testarticlest,hecorrelatiobnetween toxicityand appliedconcentrationispoor. The interactioonf thetestarticlweith thecellsisnot always repeatableor controllebdy -14- Covance20785-0-43I1CH 3M StudyNo.: T-6316.12 concentratioInn.thiscaset,heinducedtoxicitaysmeasuredby theRTG isa bettemreasureofa dose relatedresponse than appliedconcentration.Therefore,indeterminingifa doserelationshiipspresent,eithertestarticlceoncentrationor induced toxicity(RTG) may be used. This presentationof theevaluationprocessmay not encompass alltestsituationsa,nd the Study Directormay have used othercriteritao arriveatan evaluation.The reportprovidesthe reasoninginvolved when departuresfrom the above descriptionoccur. RESULTS Test ArticleHandling The testarticleformed unworkable,non-homogeneous suspensionsinwater atconcentrationsof 498, 300, 100 and 50.0 mg/mL. In DMSO, thetestarticlfeormed a solutionat500 mg/mL. For thisreason,DMSO (CAS # 67-68-5,Sigma Chemical Co.,Lot No. 99HOO20) was used asthe vehicle. N-ETFOSE T-6316 was solublein thevehicle(DMSO) at125 mg/mL, thehighestconcentration prepared foruse inthe assay. The stockused fordosing the highestconcentrationof thetest articlewas prepared inDMSO at I00-times the highestdesiredtreatmentconcentration.Further stockswere preparedby performing serialdilutionsinthevehicle.Dosing was initiatebdy performing 1:100 dilutionosf thestocksintomedium containingthecells.Alldosingwas performed with freshlyprepared testarticlsetocks. Dose Rangefinding Assay The testarticleN,-ETFOSE T-6316, was testedin a preliminarydose rangefindingassaywith a treatmentperiodof approximately4 hours both with and without S9 metabolicactivatioannd a preliminarydose rangefindingnonactivationassaywith a treatmentperiodof approximately 24 hours. Ten dose levelswere used in each case thatranged from 2.47 to 1250 @ig/mL;a vehiclecontrolwas includedunder each condition. In thepresence and absence of ratliverS9 metabolic activitywith a 4-hour treatmentperiod (Table 1),N-ETFOSE T-6316 was noncytotoxicup to 19.7gg/mL. Moderate cytotoxicitwyas induced from 39.3 to 157 gg/mL and higherconcentrationswere excessivelycytotoxicor lethal. In thenonactivationdose rangefindingassayusing a 24-hour treatmentperiod(Table2),thetest articlienduced no cytotoxicitayt2.47 gg/mL, weak cytotoxicitayt4.93 @ig/mL,and moderately high cytotoxicitayt9.85 gg/mL. Higher concentrationswere excessivelycytotoxicor lethal. Dose levelsforthe mutation assayswere based on theseresults. Mutation Assays InitialNonactivation Mutation Assav. Eleven concentrationsofN-ETFOSE T-6316 at25.3, 50.5,75.5,101, 151,201, 251, 301, 401, 501 and 601 gg/mL were initiatedT.reatmentsatand above 251 gg/mL were terminatedbecause of excessivecytotoxicityT.he remainingsix treatmentsinduced weak cytotoxicittyo high cytotoxicit(y67.6% to 14.4% relativgeowths). In -15- Covance 20785-0-43I1CH 3M StudyNo.: T-6316.12 orderfora treatmenttobe evaluatedas mutagenic inthe initianlonactivationassay,a mutant X frequency greaterthan 127.1 10-6 was required.This thresholdvaluewas equal to twicethe average mutant frequencyof theconcurrentvehiclecontrols(background mutant frequency). None of theanalyzedtreatmentinduced thislevelof mutant action(Table3). Sizingdatais shown inTable 4. A confin-natorayssaywas initiated. Conrirmatory NonactivationMutation Assay. In the confirmatorynonactivationassay,the treatmentperiodwas approximately24 hours and resultsareshown in Table 5. Ten treatments at 1.25,2.50,5.00,7.50,10.0,12.5,15.0,20.0,30.0 and 40.0 gg/mL were initiatedT.reatments at20.0,30.0 and 40.0 ptg/mL were terminatedbecause of excessivecytotoxicity.The remaining seven treatmentswere selectedformutant analysisand induced no cytotoxicittyo high cytotoxicit(y94.2% to 18.7% relativgerowths).None of theanalyzedtreatmentsinduceda mutant frequencythatexceeded the minimum criterionof 111.2x 10-6.The testarticlies, thereforec,onsiderednegativewithoutmetabolicactivationS.izingdata forthe confirmatory assay isshown inTable 6. InitialActivation Mutation Assay. Eleven treatmentsat25.3,50.5,75.5,101, 151, 201,251, 301, 401, 501 and 601 @ig/mL were initiateda,nd treatmentsatand above 151 gg/mL were ten-ninatebdecause of excessivecytotoxicityT.he remaining four doses were cloned formutant analysisand inducedmoderate tovery high cytotoxicit(y60.0% to 9.4% relativgerowths).The minimum criteriofnora positiveresponseinthistrialwas 156.7x 10-6 . None of the analyzed treatmentsinduced thislevelof mutant action(Table7). A confirmatoryassaywas perfon-ned. Sizingdataforthe initiaalssayisshown in Table 8. Confirmatory ActivationMutation Assay. In the confirmatory.4.ssawyith metabolic activation (Table 9),eleventreatmentsat5.00,10.0,20.0,30.0,40.0,50.0,60.0,80.0,100, 150 and 200 @ig/mL were initiatedT.reatments at 5.00 and 10.0 @ig/mL were terminatedbecause there were sufficienhtigherdoses availablefor analysisand the 200 @tg/mL treatmentwas terminated because of excessivecytotoxicityT.he remaining eightdosesinduced weak cytotoxicittyohigh cytotoxicit(y70.4% to 15.4% relativgerowths).None of theanalyzedtreatmentsinduceda mutant frequencythatexceededthe minimum criterioaf 122.2x 10-6 . The testarticlweas evaluatedasnegativewith metabolicactivatioinn thisassay.Sizingdata fortheconfirmatory assay isshown in Table 10. Control Values. The average cloning efficienciefsorthe vehiclecontrolswere 88.6% and 83.4% without activatioannd 84.1% and 77.3% with S9 metabolicactivationw,hich demonstrated acceptablecloningconditionsforthe assays.The positivecontrolculturesN,IMS (nonactivationa)nd MCA (activationi)nduced largeincreasesin mutant frequencythatwere greatlyin excessof theminimum criteria. SizingAnalysis. The L5178Y TK+/- mutation assayproduces a bimodal distributioonf largeand small mutant colonies.The originof thebimodal distributioonf mutant colony sizesis consideredtoreflecthetypesof geneticdamage, with thelargecoloniesderivedfrom cellswith intragenicmutationsthataffectonly theTK gene and thesmallcoloniestheresultof larger mutationsthataffectcellgrowth as well as theTK gene. Colony sizingwas performed on all -16- Covance 20785-0-43I1CH 3M StudyNo.:T-6316.12 culture(sTable4s,6,8 and10).Mutantcoloniefsromalltheculturesshowedtheexpected bimodal distributioannd mutant coloniesfrom MMS and MCA treatedculturesshowed both small and largecolonies. CONCLUSION The testarticleN,-ETFOSE T-6316, was evaluatedas negativefor inducingforward mutations at theTK locusinL5178Y mouse lymphoma cellsunder activatioannd nonactivatiocnonditions used in thisstudy. Treatmentsup to the testinglimitforthisassay were analyzed. RECORDS TO BE MAINTAINED All raw data,documentation,records,protocoland a copy of the finalreportgeneratedas a result of thisstudywillbe archivedinthe storagefacilitioefs Covance-Vienna, foratleast1 year followingsubmissionof thefinalreportto theSponsor. Afterthe 1-yearperiod,theSponsor may electtohave the aforementionedmaterialsretainedinthe storagefacilitioefsCovanceVienna foran additionalperiodof time,or sentto a storagefacilitdyesignatedby the Sponsor. REFERENCES Amacher, D.E.,PailletS,.C.,Turner, G.N.,Ray, V.A., and Salsburg,D.S. (1980) Pointmutations atthethymidinekinaselocusin L5178Y mouse lymphoma cellsIl.Test validatioannd interpretationM.utation Research,72:447-474. Clive,D. and Spector,J.F.S.(1975) Laboratoryprocedureforassessingspecificlocusmutations attheTK locusinculturedL5178Y mouse lymphoma cells.Mutation Research,31:17-29. Clive,D.,Johnson,K.O., Spector,J.F.S.B,atson,A.G., and Brown, M.M.M. (1979)Validation and characterizatioonf the L5178Y TK+/-mouse lymphoma mutagen assaysystem. Mutation Research, 59:61-108. Clive,D.,Caspary,W., Kirby,P.E.,Krehl,R.,Moore, M., Mayo, J.,and Oberly,T.J.(1987) Guide forperforming themouse lyinphoma assayformammalian cellmutagenicity.Mutation Research, 189:143-156. Hozier,J.,Sawyer,J.,Clive,D., and Moore, M.M. (1985)Chromosome 11 aberrationisnsmall colony L5178Y TK-@-mutants earlyintheirclonalhistory.Mutation Research,147:237-242. Young, R.,OveisitorkF,.,Harrington-Brock,K., Schalkowsky, S.,Moore, M., and Myhr, B. (1991) Quantativesizeanalysisof L5178 TK+l-mutant coloniesinsoftagar;an interlaboratory comparison. Environ.Molec. Mutagenesis,17,(Suppl.19),79. -17- Covance 20785-0-431ICH 3M Study No.: T-6316.12 DATA TABLES -18- Covance 20785-0-431 ICH 3M Study No.: T-6316.12 TABLE 1:CYTOTOXICITY ASSAY WITH N-ETFOSE T-6316(4-HOUR) TEST ARTICLE: N-ETFOSET-6316 STUDY NUMBER: 20785-0-431ICH TEST DATE: 05/10/2000 VEHICLE: DMSO COMMENTS ON TREATMENT: -4-HourTreatmentPeriod APPLIED CONCENTRATION ilg/mL VCC 2.47 4.93 9.85 19.7 39.3 78.5 157 313 625 1250 WITHOUT S9 ACTIVATION CELL DENSITY/mL % VEHICLE (Xlol)a CONTROL' 10.0 100.0 9.2 92.0 10.8 108.0 11.8 118.0 9.1 91.0 4.7 47.0 3.3 33.0 3.5 35.0 0.4 4.0 0.0 0.0 0.0 0.0 WITH S9 ACTIVATION CELL DENSITY/mL % VEHICLE (X IOI)a CONTROL' 10.4 100.0 10.8 103.8 9.4 90.4 11.7 112.5 9.2 88.5 5.1 49.0 2.8 26.9 ---2.4 23.1 0.3 2.9 0.0 0.0 0.0 0.0 aCelldensitydeterminedby hemocytometer brelativteovehiclecontrolcelldensityforalltreatments cVC =Vehiclecontrol1,% DMSO -19- Covance 20785-0-43I1CH 3M StudyNo.: T-6316-12 TABLE 2:CYTOTOXICITY ASSAY WITH N-ETFOSE T-6316 WITHOUT S9 ACTIVATION (24-HOUR) TEST ARTICLE: N-ETFOSE T-6316 STUDY NUMBER: 20785-0-431 ICH TEST DATE: 05/10/00 VEHICLE: DMSO COMMENTS ON TREATMENT: -24-Hour TreatmentPeriod APPLIED CONCENTRATION mg/mL VCC 2.47 4.93 9.85 19.7 39.3 78.5 157 313 625 1250 CELL DENSITY/ML (Xlol)a DAY1 11.0 12.1 7.2 5.7 0.3* 0.0* 0.0* NTC NTC NTC NTC DAY2 7.0 6.4 7.3 3.3 1.0 0.0 0.0 NTC NTC NTC NTC 'Celldensitydetermined by hemocytometer brelativetovehiclecontrolcelldensityforalltreatments ':VC = Vehicle control,1% DMSO NTC = Not counted,cytotoxic *Not subcultured % VEHICLE CONTROL' 100.0 100.6 68.3 24.4 3.9 0.0 0.0 --------- -20- Covance 20785-0-431 ICH 3M Study No.: T-6316.12 TABLE 3:INITIAL MUTATION ASSAY WITHOUT ACTIVATION A. TEST ARTICLE: N-ETFOSE T-6316 B. GENETICS ASSAY NO.: 20785-0-431ICH C. VEHICLE: DMSO D. SELECTIVE AGENT: TFT 3.0pg/mL E. TR-EATMENT DATE: OS/16/2000 F. CELLS ANALYZED: 3x106 G. TREATMENT PERIOD: -4 hours H. EXPRESSION PERIOD: 2 days TestCondition DailyCell Cumulative Total Total Cloning Counts(Cell/mL, RSGA Mutant Viable Efficienc@b IOE5 Units) ColoniesColonies Day I Day 2 NonactivationControls' AVG AVG vc vc VehicleControl VehicleControl VehicleControl 10.0 14.2 15.8 188 501 83.5 12.2 11.5 15.6 157' 544 90.7 11.7 12.2 15.9 15.7 160h 549 91.5 88.6 Relative Mutant Growth Frequency (IOE-6 UnitS)d 94.5 74.9 101.5 57.5 104.1 58.2 ,MMS 13 gg/mL MMS 13 pg/mL 6.9 12.4 9.5 8.2 12.0 10.9 389' 395 271 45.1 225' 37.5 30.8 287.9' 29.4 350.8' TestCompound pg/mL Relativeto Vehicle Control Relativeto Vehicle Control 25.3 7.8 14.2 78.2 183 459 86.4 67.6 79.8 50.5 4.6 10.6 34.4 170h 483 91.0 31.3 70.2 75.5 2.89 9.7 20.5 142 469 88.3 18.1 60.5 101 1.39 8.2 17.4 171 465 87.5 15.2 73.7 151 2.19 8.5 18.0 145 485 91.4 16.4 59.8 201 2.09 8.0 16.9 173 451 84.8 14.4 77.0 'RSG (Day I Count/3) (Day 2 Count)/3(orDay I Count ifnotsubcultured) bc]oningEfficiency= TotalViableColony Count/Number of CellsSeeded * 100 crelativGerowth = (RelativSeuspensionGrowth * RelativeCloning Efficiency)100 dmutant Frequency = (TotalMutant Colonies/TotaVliableColonies)* 2x IOE-4 Decimal ismoved to expressthefrequencyinunitsof IOE-6 'VehicleControl= I% DMSO PositiveControl:MMS = Methyl methanesulfonate fmutagenic.Exceeds Minimum Criterioonf 127.1X IOE-6 gnot Subcultured hOne platecontaminated.Totalcountscalculatebdy usinga weight proportion Covance 20785-0-431 ICH 3M Study No.: T-6316.12 TABLE 4: SIZING DATA FOR INITIAL MUTATION ASSAY WITHOUT ACTIVATION A. TEST ARTICLE: N-ETFOSET-6316 B. GENETICS ASSAY NO.: 20785-0-431 ICH C. VEHICLE: DMSO D. SELECTIVE AGENT: E. TREATMENT DATE: TFT 3.0pg/mL 05/16/2000 Test Condition VehicleControl' Conc. I% 1% 1% Cum. RSG Day I Day 2 88.5 108.0 103.5 100.2 99.0 100.7 Cloning EfficienCyb Abs % Rel % 83.5 90.7 91.5 94.3 102.5 103.3 Relative Growth' 94.5 101.5 104.1 Mutant Frequency (X I0-6)d Total Small Large 74.9 57.5 58.2 42.3 43.0 34.8 32.7 14.5 23.4 MMSF (pg/mL) 13 61.1 60.4 45.1 50.9 30.8 287.9 214.1 73.8 13 72.6 69.5 37.5 42.4 29.4 350.8 169.6 181.2 Test Article(@Lg/mL) 25.3 50.5 75.5 101 69.0 40.7 24.8 11.5 78.2 34.4 20.5 17.4 76.6 80.6 78.2 77.5 86.4 91.0 88.3 87.5 67.6 31.3 18.1 15.2 79.8 70.2 60.5 73.7 40.9 42.8 34.0 44.6 151 18.6 18.0 80.9 91.4 201 17.7 16.9 75.1 84.8 16.4 59.8 35.1 14.4 77.0 47.9 'Cum. RSG = Cumulative Suspension Growlh Relativetothe Average Vehicle ControlSuspension Growth 39.0 27.4 26.5 29.1 24.7 29.1 bcloning Efficiency= Total ViableColony Count/Number of CellsSeeded * 100 'RelativeGrowth = (RelativeSuspensionGrowth * RelativeCloning Efficiency/) 100 dmutant Frequency = (TotalMutant Colonies/TotalViable Colonies) * 2x IOE-4 Decimal ismoved to expressthe frequencyinunitsof IOE-6 Expressed as Total Mutant Frequency,Small Colony Mutant Frequency and Large Colony Mutant Frequency 'VehicleControl= DMSO fpositiveControl:MMS = Methyl methanesulfonate Colony Counts increasedby 9.099% tocompensate forareaof dish not scanned -22- Covance 20785-0-431 ICH 3M Study No.: T-6316.12 TABLE 5: CONFIRNIATORY A. TEST ARTICLE: N-ETFOSET-6316 B. GENETICS ASSAY NO.: 20785-0-431 ICH C. VEHICLE: DMSO D. SELECTIVE AGENT: TFT 3.0 pg/mL MUTATION ASSAY WITHOUT ACTIVATION E. TREATMENT DATE: 06/07/2000 F. CELLS ANALYZED: 3x]06 G. TREATMENT PERIOD: -24 hours H. EXPRESSION PERIOD: 2 days Test Condition Daily CellCounts Cumulative (Cell/mL,IOE5 Units) RSGA Day I Day 2 Day 3 NonactivationControls' AVG vc Total Total Mutant Viable Colonies Colonies Cloning Efficiencby AVG vc Relative Growth (%)C Mutant Frequency (IOE-6 UnitS)d Vehicle Control Vehicle Control Vehicle Control MMS 6.5 @Lg/mL MMS 6.5gg/mL Test Compound pg/mL 12.0 7.9 12.0 43.1 133 14.3 6.2 11.4 37.4 154 14.7 6.1 16.4 54.5 44.7 128 9.5 4.9 6.8 11.7 571 9.6 4.5 5.2 8.3 574 Relativeto Vehicle Control 464 77.3 87.4 597 99.5 99.9 441 73.5 83.4 107.4 211 35.1 11.0 233 38.9 8.7 Relativeto Vehicle Control 57.4 51.6 57.9 542.0' 491.6' 1.25 10.0 7.5 10.6 65.9 173 568 113.6 74.9 61.0 2.50 9.3 6.6 16.2 82.4 136 463 92.4 76.2 59.0 5.00 12.1 9.1 12.2 111.4 158 423 84.6 94.2 74.7 7.50 9.4 6.5 15.7 79.5 147 433 86.6 68.8 68.0 10.0 9.6 7.0 10.8 60.2 148 552 110.3 66.4 53.8 12.5 6.6 5.9 12.2 39.4 133 424 84.8 33.4 62.7 'RSG 15.0 6.3 3.99 13.5 21.2 169 442 88.3 18.7 76.5 [Treatmenttermination(Day 1)celldensity/3x1051x [Day 2 celldensity/3xl05 orDay I densityifnot splitback] x [Day 3 celldensity/3xlO5or Day 2 densityifnot splitback] bcloning Efficiency= TotalViableColony CountfNumber of CellsSeeded * 100 rrelativeGrowth = (RelativeSuspensionGrowth * RelativeCloning Efficiency) 100 dmutant Frequency = (TotalMutant Colonies/TotalViable Colonies) 2x IOE-4 Decimal ismoved to expressthefrequency inunitsof IOE-6 'VehicleControl= I% DMSO PositiveControl:MMS = Methyl methanesulfonate fmutagenic.Exceeds Minimum Cfiterionof 111.2X IOE-6 gnot subcultured -23- Covance 20785-0-431ICH 3M Study No.: T-6316.12 TABLE 6: SIZING DATA FOR CONFIRMATORY A. TEST ARTICLE: N-ETFOSET-6316 B. GENETICS ASSAY NO.: 20785-0-431 ICH C. VEHICLE: DMSO D. SELECTIVE AGENT: TFT 3.0pg/mL E. TREATMENT DATE: 06/07/2000 Cum. RSG Test Condition VehicleControl' Conc. 1% 1% 1% Day I Day 2 Day 3 87.8 104.6 107.6 104.1 97.4 98.5 94.3 83.8 121.9 MUTATION ASSAY WITHOUT ACTIVATION Cloning Efficiency, s% Re]% 77.3 99.5 73.5 92.7 119.3 88.1 Relative Growthc (%) 87.4 99.9 107.4 Mutan(txFlrequency o-6)d Total Small Large 57.4 51.6 57.9 24.5 24.5 32.2 32.9 27.1 25.7 MMS'(pg/mL) 6.5 69.5 51.1 26.2 35.1 42.1 6.5 70.2 47.4 18.6 38.9 46.7 11.0 542.0 336.8 205.2 8.7 491.6 316.8 174.8 Test Article(@ig/mL) 1.25 2.50 5.00 7.50 10.0 12.5 15.0 73.2 68.0 88.5 68.8 70.2 48.3 46.1 82.4 67.4 120.9 67.1 73.8 42.8 20.8 65.9 82.4 111.4 79.5 60.2 39.4 21.2 94.7 77.1 70.6 72.2 92.0 70.7 73.6 acum. RSG = Cumulative Suspension Growth Relative to the Average 113.6 92.4 84.6 86.6 110.3 84.8 88.3 74.9 76.2 94.2 68.8 66.4 33.4 18.7 61.0 59.0 74.7 68.0 53.8 62.7 76.5 Vehicle Control SuspensionGrowth 29.9 27.8 37.1 34.3 31.2 35.0 39.5 bcloning Efficiency = Total Viable Colony CountfNumber of Cells Seeded * 100 'Relative Growth = (Relative Suspension Growth * Relative Cloning Efficiency) / 100 dM utant Frequency = (Total Mutant Colonies/Total Viable Colonies) * 2x IOE-4 Decimal is moved to express the frequency in units of IOE-6 Expressed as Total Mutant Frequency, Small Colony Mutant Frequency and Large Colony Mutant Frequency 'Vehicle Control = DMSO fpositiveControl: MMS = Methyl methanesulfonate Colony Counts increased by 9.099% to compensate for area of dish not scanned 31.1 31.1 37.6 33.8 22.5 27.8 37.0 -24- Covance 20785-0-431ICH 3M Study No.: T-6316.12 TABLE 7: INITIAL MUTATION A.TEST ARTICLE: N-ETFOSET-6316 B. GENETICS ASSAY NO.: 20785-0-431ICH C. VEHICLE: DMSO D. SELECTIVE AGENT: TFT 3.0pg/mL ASSAY WITH ACTIVATION E. TREATMENT DATE: 05/16/2000 F.CELLS ANALYZED: 3x106 G. TREATMENT PERIOD: -4 hours H. EXPRESSION PERIOD: 2 days TestCondition DailyCell Cumulative Counts(Cell/mL, RSGA IOE5 Units) Total Total Mutant Viable Colonies Colonies Day I Day 2 S9-ActivatioCnontrols' AVG S9 Batch Number: 955 vc Cloning Efficiencyb Relative Growth (%)C Mutant Frequency (IOE-6 Un its)d AVG vc VehicleControl 12.7 17.3 24.4 170h 437 72.9 112.5 77.9 VehicleControl 11.1 15.0 18.5 201 503 83.8 98.0 79.8 VehicleControl 10.8 11.3 13.6 18.8 221 573 95.5 84.1 81.8 77.3 MCA 2 pg/mL MCA 4 pg/mL 7.6 15.1 12.8 6.2 15.6 10.7 605 381 63.5 607 391 65.1 51.1 318.1' 44.2 310.6' Test Compound pg/mL Relativeto Vehicle Control Relativeto VehicleControl 25.3 8.8 11.9 61.8 167 490 97.1 50.5 3.19 13.0 23.0 149 476 94.3 75.5 1.69 7.5 13.3 178 490 97.1 101 0.59 6.2 11.0 167 433 85.9 'RSG = (Day I Count/3) (Day 2 Count)/3(orDay I Count ifnot subcultured) bC loningEfficiency= TotalViableColony Count/Number of CellsSeeded * 100 'RelativGerowth = (RelativeSuspensionGrowth * RelativeCloningEfficiency)100 60.0 68.2 21.7 62.8 12.9 72.6 9.4 77.1 dmutantFrequency= (TotalMutant Colonies/TotaVliableColonies)* 2x]OE-4 Decimal ismoved toexpressthefrequencyinunitsof IOE-6 'VehicleControl= I% DMSO PositiveControl:MCA = Methylcholanthrene fmutagenic.Exceeds Minimum Criterioonf 156.7X IOE-6 gnot subcultured hone platecontaminated.Totalcountscalculatebdy usinga weightproportion -25- Covance 20785-0-431ICH 3M Study No.: T-6316.12 TABLE 8: SIZING DATA FOR INITIAL MUTATION ASSAY WITH ACTIVATION A. TEST ARTICLE: N-ETFOSE T-6316 B. GENETICS ASSAY NO.: 20785-0-431 ICH C. VEHICLE: DMSO D. SELECTIVE AGENT: TFT 3.0pg/mL E. TREATMENT DATE: 05/16/2000 Cum. RSG (%)' Test Condition Vehicle Control' Conc. 1% 1% I% Day I Day 2 110.1 96.2 93.6 129.7 98.3 72.0 Cloning EfficienCyb Abs % Rel % 72.9 83.8 95.5 86.7 99.7 113.6 Relative Growth' (%) 112.5 98.0 81.8 Mutant Frequency (X 10-6)1 Total Small Large 77.9 79.8 77.3 35.3 49.9 46.9 42.6 29.9 30.5 MCA'(@ig/mL) 2 65.9 67.7 63.5 75.5 51.1 318.1 150.1 167.9 4 53.8 57.1 65.1 77.4 44.2 310.6 166.5 144.1 TestArticle(pg/mL) 25.3 50.5 75.5 101 76.3 26.9 13.9 4.3 61.8 23.0 13.3 11.0 81.6 97.1 79.3 94.3 81.6 97.1 72.2 85.9 60.0 21.7 12.9 9.4 68.2 62.8 72.6 77.1 38.8 38.5 42.8 55.4 29.4 24.3 29.8 21.7 'Cum. RSG = Cumulative Suspension Growth Relativeto theAverage VehicleControl Suspension Growth bcloning Efficiency= TotalViable Colony Count/Number of CellsSeeded * 100 'RelativeGrowth = (Relafl'vSeu'spension Growth * RelativeCloning Efficiency/) 100 dmutant Frequency = (TotalMutant Colonies@'rotaVliable Colonies) * 2x IOE-4 Decimal ismoved toexpressthefrequency inunitsof IOE-6 Expressed as Total Mutant Frequency, Small Colony Mutant Frequency and Large Colony Mutant Frequency 'VehicleControl= DMSO fpositivCeontrol:MCA = Methylcholanthrene Colony Counts increasedby 9.099% to compensate forareaof dish not scanned -26- TABLE 9: CONFIRMATORY A. TEST ARTICLE: N-ETFOSET-6316 B. GENETICS ASSAY NO.: 20785-0-431ICH C. VEHICLE: DMSO D. SELECTIVE AGENT: TFT 3.0pg/mL Covance 20785-0-431ICH 3M Study No.: T-6316.12 MUTATION ASSAY WITH ACTIVATION E. TREATMENT DATE: 06/07/2000 F. CELLS ANALYZED: 3x 106 G. TREATMENT PERIOD: -4 hours H. EXPRESSION PERIOD: 2 days TestCondition DailyCell Cumulative Total Total Counts(Cell/mL, RSG a Mutant Viable IOE5 Units) Colonies Colonies Cloning Efficiencb y Day I Day 2 S9-ActivatioCnontrols' AVG AVG S9 Batch Number: 955 vc vc Relative Growth (%)C Mutant Frequency (IOE-6 Un its)d VehicleControl VehicleControl VehicleControl MCA 2 @Lg/niL MCA 4 @Lg/niL 9.4 16.9 17.7 128 9.1 15.9 16.1 149 14.3 13.9 22.1 18.6 147 7.3 13.7 11.1 472 9.1 12.6 12.7 412 479 79.8 97.9 461 76.9 85.9 452 75.3 77.3 115.5 443 73.8 57.0 405 67.5 59.7 53.3 64.8 65.2 213.3' 203.8' TestCompound pg/mL Relativeto Vehicle Control Relativeto Vehicle Control 20.0 30.0 40.0 50.0 60.0 80.0 100 150 8.0 19.4 7.5 12.0 5.5 17.0 5.2 14.2 3.49 14.4 2.19 13.9 2.29 10.5 2.89 7.5 92.7 53.8 55.8 44.1 25.8 24.9 18.8 13.4 131 352 132 525 128 433 122 445 100 444 122 453 135 464 153 532 75.9 113.1 93.3 95.9 95.7 97.6 99.9 114.7 70.4 74.3 60.8 50.3 52.1 58.9 42.3 54.9 24.7 45.2 24.3 54.0 18.8 58.4 15.4 57.4 aRSG (Day ICount/3) (Day 2 Count)/3(orDay ICount ifnotsubcultured) bcloningEfficiency= TotalViableColony Count/Number ofCellsSeeded * 100 'RelativGerowth = (RelativeSuspensionGrowth * RelativeCloningEfficiency)100 dMUtantFrequency= (TotalMutant Colonies/TotaVliableColonies) 2x IOE-4 Decimal ismoved to expressthefrequencyinunitsof IOE-6 'VehicleControl= I% DMSO PositiveControl:MCA = M ethylcholanthrene rmutagenic.Exceeds Minimum Criterioonf 122.2X IOE-6 gnot Subcultured -27- Covance 20785-0-431ICH 3M Study No.: T-6316.12 TABLE 10: SIZING DATA FOR CONFIRMATORY MUTATION ASSAY WITH ACTIVATION A. TEST ARTICLE: N-ETFOSE T-6316 B. GENETICS ASSAY NO.: 20785-0-431 ICH C. VEHICLE: DMSO D. SELECTIVE AGENT: TFT 3.0@ig/mL E. TREATMENT DATE: 06/07/2000 Test Condition Vehicle Control' Conc. I% 1% 1% Cum. RSG Day I Day 2 86.0 83.2 130.8 94.9 86.4 118.7 Cloning Efficiency' Abs % Rel % 79.8 76.9 75.3 103.2 99.5 97.3 Relative Growth' (%) 97.9 85.9 115.5 Mutant Frequency (X I0-I)d Total Small Large 53.3 23,7 64.8 28.4 65.2 26.6 29.6 36,4 38.6 MCA, (pg/ML) 2 66.8 59.7 73.8 95.5 57.0 213.3 86.2 127.1 4 83.2 68.5 67.5 87.2 59.7 203.8 97.0 106.7 TestArticle(pg/niL) 20.0 30.0 40.0 50.0 60.0 80.0 100 150 73.2 68.6 50.3 47.6 31.1 19.2 20.1 25.6 92.7 53.8 55.8 44.1 25.8 24.9 18.8 13.4 58.7 87.5 72.2 74.2 74.0 75.5 77.3 88.7 75.9 113.1 93.3 95.9 95.7 97.6 99.9 114.7 70.4 60.8 52.1 42.3 24.7 24.3 18.8 15.4 74.3 50.3 58.9 54.9 45.2 54.0 58.4 57.4 32.8 21.6 29.7 29.4 23.6 28.4 30.1 29.5 41.5 28.7 29.2 25.5 21.6 25.5 28.2 27.9 'Cum. RSG = Cumulative Suspension Growth Relativeto theAverage Vehicle ControlSuspension Growth bcloning Efficiency= TotalViable Colony Count/Number of CellsSeeded * 100 'RelativeGrowth = (RelativeSuspensionGrowth * RelativeCloning Efficiency/)100 dmutant Frequency = (TotalMutant Colonies/TotalViable Colonies)* 2x IOE-4 Decimal ismoved toexpressthe frequencyinunitsof IOE-6 Expressed asTotal Mutant Frequency,Small Colony Mutant Frequency and Large Colony Mutant Frequency 'VehicleControl= DMSO fpositiveControl:MCA = M ethylcholanthrene Colony Counts increasedby 9.099% tocompensate forareaof dish not scanned -28- Covance 20785-0-43I1CH 3M StudyNo.: T-6316.12 HISTORICAL CONTROL DATA NonactivatiSotnudies Pooled negativeand vehiclecontrolmutant frequencies Mean ( SD) 53.0 22.0x 10-6 Range 20.5 to 114.8 x 10 Number of experiments 52 Number of controls 156 Positivecontrolmutant frequencies(6.5@ig/mL methyl methanesulfonate) Mean ( SD) 272.7 135.7x 10-6 Range 115.9to632.lx 10-6 Number of experiments 51 Number of controls 51 Positivecontrolmutant frequencies(13 @ig/mL methyl methanesulfonate) Mean ( SD) 483.9 315.2x 10' Range 176.1 to 1996.4 x 10-6 Number of experiments 52 Number of controls 52 ActivationStudies Pooled negativeand vehiclecontrolmutant .frequencies Mean (:ESD) 65.3 27 1 x 10-6 Range 27.6 to 150.3 x 10-6 Number of experiments 54 Number of controls 162 Positivecontrolmutant frequencies(2.0@ig/mL 3-methylcholanthrene) Mean ( SD) 454.5 166.2x 10-6 Range 204.8 to 787.8 x 10-6 Number of experiments 54 Number of controls 54 Positivecontrolmutant frequencies(4.0gg/mL 3-methylcholanthrene) Mean ( SD) 567.0 248.3 x 10' Range 218.9 to 1414.9 x 10-6 Number of experiments 54 Number of controls 54 Because some experiments containedmultiplecontrols,the number of independentcontrol culturesexceeded the number of experiments. -29-