BiopharmaceuticsLecture :1

Module Introduction and Introduction to Biopharmaceutics

Assist. Lecturer Ali Yaseen Ali

Dept. of Pharmaceutics School of Pharmacy

University of Sulaimani 1

AssistLecturerAliYaseenAli

• Education• BScPharmacy(HMU)• MScIndustrialPharmaceuticalSciences(UniversityofBrighton)

• Nanoparticles (Carbon)inDrugDelivery(CNT)• NanomedicineCPD(UniversityofOxford)

• Room:PharmaceuticsDept.(Newbuilding)• Wednesdays

• Drop-inoremailwithspecificquery:ali.yaseen@univsul.edu.iq

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Syllabus

• Introductiontobiopharmaceutics

• Biopharmaceuticalaspectsoforaldrugs:• PhysiologicalfactorsaffectingtheabsorptionofdrugsfromGIT• PhysicochemicalFactorsofdrugsaffectingabsorption• DosageformfactorsaffectingthedrugabsorptionfromtheGIT

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LecturesOrganisation

• TheoreticalLectures:• 2hoursweekly

• Wednesdays

• Practice(LabSessions)• 3hours

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RecommendedTexts

• Aulton'sPharmaceutics:TheDesignandManufactureofMedicines,M.E.Aulton,ChurchillLivingstone,2007.

• ShargelL,YuAB,(Eds.),AppliedBiopharmaceuticsandPharmacokinetics.

• PharmaceuticalDosageformsandDrugDeliverySystemsbyHawardA.Ansel;latestedition

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Assessment

• Mid-term(semester):40%• Theory:writtenexam(1-1.5hour)25%• Practical:15%

• Labsessionworks,attendance,quizzes

• End-of-Semester:60%• Practical:writtenexam(1hour)10%• Theoretical:writtenexam(3hours)50%

• Passmarkis50%

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AssessmentCriteria

• MCQandshortanswerquestions• Factualknowledge• Understandingofkeyconcepts• Abilitytoapplyknowledgeofconceptstonewscenarios• Calculations

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AssessmentCriteria

• Writtenexam– longanswerquestions• Demonstrateunderstanding/knowledgeoftheissuesrelatingtoappropriatetopics

• Consequences/implicationsof….• Abilitytoconstructanargumentsupporting/refutingaposition(s)• compareandcontrasttwopositions• Abilitytomakeappropriateanalysisofdata• Calculations

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Specimenquestions

• Willbeprovidedwithspecimenquestionsandmarkingschemes

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Thelearningpyramid

Application

Understanding

Knowledge

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IntroductiontoBiopharmaceutics

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Pharmacy

1. MedicinalChemistry(DrugDiscovery)• Pharmacognosy(NaturalProductsChemistry)

2. Pharmaceutics(DrugDevelopment,Dosageform)3. PharmacologyandToxicology4. Clinicalpharmacyandpharmacypractice

Pharmaceutics

• 1st :PharmacyCalculations• 2nd :PhysicalPharmacy• 3rd :PharmaceuticalCompounding• 4th :Biophamaceutics andPharmacokinetics• 5th :IndustrialPharmacy

Drugs

• Asubstanceintendedforuseinthediagnosis,cure,mitigation,treatment,orprevention ofdisease.

• Asubstance(otherthanfood)intendedtoaffectthestructureoranyfunctionofthebody.

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DosageForms

• Adosageformisthephysicalforminwhichadrugisproducedanddispensed,suchasatablet,acapsule,oraninjectable.

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RouteofAdministration

• Arouteofadministrationisawayofadministering adrugtoasiteinapatient

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WhatisBiopharmeceutics?

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Pharmacokinetics

• IsthescienceofkineticsofdrugAbsorption,Distribution,MetabolismofElimination(ADME)

• ItstudiesthetimecourseofADME.

• Itisusedinclinicalsettingstoenhancesafeandeffectivetherapeuticmanagementofindividualpatients.

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BiopharmaceuticsPhysicochemical

properties

DosageformRouteof

Administration

Bioavailability(Rate&Extent)

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Biopharmaceutics• Sciencethatstudieshowthephysicochemicalpropertiesofthedrug,itsdosageformandtherouteofadministrationaffecttherate andextent ofabsorption(Bioavailability).

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Background

(AultonandTaylor2013)

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Bioavailability

• Relativeamountofanadministereddoseofadrugthatreachesthesystemiccirculationintact

• Rate• atwhichthisoccurs

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Bioavailability• TheprimaryconcernofBiopharmaceutics

• IV(100%)bioavailable.

• Otherroutes?• Bioavailabledose

• Fractionofadministereddosereachingsystemiccirculationinanunchangedform

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Bioavailability- definition

• Rate andextent towhichanactiveagentisabsorbed intothesystemiccirculation.

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RoutesofAdministration

25(AultonandTaylor2013)

Concentrationofdruginblood

• [bounddrug]+[unbounddrug]=[totaldrug]

• Representsamountofdrugatsiteofaction• Dependson:

– TheamountofdrugAbsorbed– TheextentofDistributionofthedrug– TherateofMetabolismofthedrug– TherateofEliminationofthedrug

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TypicalBlood-plasmaConcentrationTimeCurveofATabletTakenBySingleDose

0 1 2 3 4 5 6 7 8 9 10 11 120

1

2

3

4

5

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Duration of action

Therapeutic range

Minimum effective concentration

Maximum safe concentration

Elimination phaseAbsorptionphase

Avera

ge se

rum co

ncntr

ation

(mcg

/ml)

Time after drug administration (h)

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Oralroute

• Mostpopular• Naturalandconvenientforpatient• Relativelyeasytomanufactureoraldosageforms

• Compact• Notsterilized• Inexpensive

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BiopharmaceuticalFactorsinfluencingtherateandextentofabsorption• Foodseatenbypatient?

• Effectofdiseasestateondrugabsorption

• Ageofpatient

• Siteofabsorption

• Co-administrationofotherdrugs

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BiopharmaceuticalFactorsinfluencingtherateandextentofabsorption

• Physicalandchemicalpropertiesofdrug

• Typeofdosageform

• Compositionandmethodofmanufactureofthedosageform

• Sizeofdose

• Frequencyofadministration

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ConditionsinBiopharmaceutics

Foragivendrug,bioavailabilitymayvaryif:1. Samedosageform,butdifferentroute

2. Sameroutebutdifferentdosageform

3. Samerouteandsametypeofdosageformbutdifferentformulations

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Foragivendrug,bioavailabilitymayvaryif:

• Samedosageform,butdifferentroute

• DiphenhydramineOralSolutionandInjection• Bothsolutions

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EquivalentdosesofsamedrugadministeredbyIVbolusinjectionandbytheoralroute.

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Terminology

• Onsetofaction:• Timethedrugtakestoproduceeffect

• Durationofaction:• Lengthoftheeffect

0 1 2 3 4 5 6 7 8 9 10 11 120

1

2

3

4

5

6

Duration of action

Therapeutic range

Minimum effective concentration

Maximum safe concentration

Elimination phaseAbsorptionphase

Avera

ge se

rum co

ncntr

ation

(mcg

/ml)

Time after drug administration (h)

Onsetofaction

Timeofonset ofactionfordifferentdosageforms

• Seconds• Minutes• Minutestohours• Severalhours• Days• Varies

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Timeofonsetofactionfordifferentdosageforms

• Seconds- IVinjections

• Minutes• IM&SCinjections;buccaltablets;aerosols;gases

• Minutestohours• Short-termdepotinjections,solutions,suspensions

• Soliddosageforms:Powders,granules,capsules,tablets,MRtablets

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• Severalhours– EC(EntericCoated)formulations

• Days– Depotinjections,implants

• Varies– topicalpreparations

Bloodlevelcurvesofnitroglycerinfollowingadministrationofdosageformsbyvarious

routes

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Foragivendrug,bioavailabilitymayvaryif:

• Sameroutebutdifferentdosageform• Alloralroute

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Foragivendrug,bioavailabilitymayvaryif:

• Samerouteandsametypeofdosageformbutdifferentformulations• oralaqueoussuspensions

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Threedifferentformulationsofthesamedrugadministeredinequalsingledosesbythesamenon-parenteralroute.

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Biopharmaceuticsindrugdevelopmentprocess

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DosageFormDesign

DosageFormDesign

Drug

BiopharmaceuticalConsideration

TherapeuticConsideration

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RationalDrugDesign

• Choosingtherouteofadministrationcarefullyanddesigningthedrugproduct properly.

Slowandsustained

NoAbsorption

ABSORPTION

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Rapidandcomplete

Dosageregimen1. Dose

2. Frequency

• 500mgamoxicillincapsulestobetakenevery8hours

• Determinedfrombiopharmaceuticalconsideration

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Poorbiopharmaceuticalproperties

1. Poorandvariablebioavailability

2. Difficultieswithbioequivalenceofformulations

3. Multipledailydosing

4. Requirementforanon-conventionaldeliverysystem

5. Longandcostlydevelopmenttimes46

FurtherReadings

• Aulton,M.E.andK.M.Taylor(2013).Aulton'spharmaceutics:thedesignandmanufactureofmedicines,ElsevierHealthSciences.

• Shargel,L.,S.Wu-PongandA.B.Yu(2007).Appliedbiopharmaceutics&pharmacokinetics,McGraw-Hill.

• Allen,L.V.,&Ansel,H.C.(2014). Ansel's pharmaceuticaldosageformsanddrugdeliverysystems.

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ThankYou

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