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Pharmacology of Pharmacology of TacrolimusTacrolimusOintmentOintment

William Fitzsimmons, Pharm.D.William Fitzsimmons, Pharm.D.Vice PresidentVice President

Drug Development Project Management Drug Development Project Management Fujisawa Healthcare, Inc.Fujisawa Healthcare, Inc.

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Pharmacology ofPharmacology ofTacrolimus OintmentTacrolimus Ointment

Topical macrolide (non-steroidal) Topical macrolide (non-steroidal) immunomodulatorimmunomodulator

Inhibits calcineurin phosphatase activity Inhibits calcineurin phosphatase activity in T-lymphocytes leading to decreased in T-lymphocytes leading to decreased synthesis of cytokines associated with synthesis of cytokines associated with atopic dermatitisatopic dermatitis

Decreases inflammatory mediator Decreases inflammatory mediator release from skin mast cells and release from skin mast cells and basophilsbasophils

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Nonclinical Studies ofNonclinical Studies ofTacrolimus OintmentTacrolimus Ointment

27 studies conducted27 studies conducted

3 chronic studies3 chronic studies– 104-week topical carcinogenicity in 104-week topical carcinogenicity in

B6C3FB6C3F11 mice mice

– 52-week photocarcinogenicity in52-week photocarcinogenicity inhairless micehairless mice

– 52-week topical toxicity in micropigs52-week topical toxicity in micropigs

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Topical Carcinogenicity StudyTopical Carcinogenicity Studyin Micein Mice

104 weeks (lifetime of animal)104 weeks (lifetime of animal)

No increase in skin tumorsNo increase in skin tumors

Mice had 89 times higher systemic Mice had 89 times higher systemic tacrolimus exposure than typical tacrolimus exposure than typical atopic dermatitis patients atopic dermatitis patients

Increased incidence of non-Increased incidence of non-cutaneous lymphomas in 0.1% cutaneous lymphomas in 0.1% tacrolimus grouptacrolimus group

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Photocarcinogenicity StudyPhotocarcinogenicity Studyin Hairless Micein Hairless Mice

52 week study with controlled UVR 52 week study with controlled UVR exposureexposure

All animals develop skin tumorsAll animals develop skin tumors

Median time to onset of tumor is the Median time to onset of tumor is the primary endpointprimary endpoint

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Photocarcinogencity in Hairless MicePhotocarcinogencity in Hairless Mice(combined male & female)(combined male & female)

MTO: Median Tumor Onset: mortality adjusted time at which one-half of the group has one or more tumors > 1 mm2.Tumor Amplification Factor: relative influence of a test article on the response of skin to UVR exposure.

TacrolimusTacrolimus(%)(%)

MTO (Weeks)MTO (Weeks)

Tumor Tumor Amplification Amplification FactorFactor

UntreatedUntreatedControlControl

4242

1.01.0

VehicleVehicle

3434

1.31.3

0.030.03

3535

1.31.3

0.10.1

3434

1.31.3

0.30.3

3131

1.51.5

1.01.0

3131

1.51.5

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Topical Toxicity StudyTopical Toxicity Studyin Micropigsin Micropigs

52 weeks52 weeks

Micropig (juvenile to adult)Micropig (juvenile to adult)

Up to 3% tacrolimus ointmentUp to 3% tacrolimus ointment

Blood levels similar to humansBlood levels similar to humans

40% Body Surface Area treated40% Body Surface Area treated

No noteworthy topical or systemic No noteworthy topical or systemic findingsfindings

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Nonclinical StudiesNonclinical StudiesConclusionsConclusions

Tacrolimus is not a mutagen or carcinogenTacrolimus is not a mutagen or carcinogen

In a 2 year mouse study, there was no increase in In a 2 year mouse study, there was no increase in skin tumorsskin tumors

In mice, high skin permeability and high blood In mice, high skin permeability and high blood levels resulted in immunosuppression and levels resulted in immunosuppression and lymphomalymphoma

In a mouse model, median time to onset of photo-In a mouse model, median time to onset of photo-induced skin tumors is reduced with vehicle and induced skin tumors is reduced with vehicle and active treatmentactive treatment

No noteworthy topical or systemic toxicity in No noteworthy topical or systemic toxicity in micropigsmicropigs

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Early Patch Testing in HumansEarly Patch Testing in HumansTacrolimus OintmentTacrolimus Ointment

No evidence for:No evidence for:

– Contact hypersensitivityContact hypersensitivity

– PhototoxicityPhototoxicity

– PhotosensitizationPhotosensitization

– Reduction of collagen synthesis in Reduction of collagen synthesis in the skinthe skin

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Pharmacokinetic Study -008Pharmacokinetic Study -008in Atopic Dermatitis Patientsin Atopic Dermatitis Patients

0.3% tacrolimus ointment0.3% tacrolimus ointment– Single application on days 1 and 8Single application on days 1 and 8

– Twice daily application days 2 through 7Twice daily application days 2 through 7

Protocol-defined area of applicationProtocol-defined area of application– Pediatric: 50 or 100 cmPediatric: 50 or 100 cm22

– Adult: 100 to 5000 cmAdult: 100 to 5000 cm22

Minimal systemic absorption Minimal systemic absorption (bioavailability (bioavailability << 0.5%) 0.5%)

No systemic accumulationNo systemic accumulation

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Phase III US StudiesPhase III US Studies

Distribution of TacrolimusDistribution of TacrolimusBlood ConcentrationBlood Concentration

0.03% Tacrolimus Ointment0.03% Tacrolimus Ointment

0%

20%

40%

60%

80%

100%

<0.5 0.5 - <1 1 - <2 2 - <5 > 5

Highest Observed TacrolimusWhole Blood Concentration (ng/mL)

% P

atie

nts

Adults Pediatric

(n=195) (n=25)

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Phase II/III US StudiesPhase II/III US Studies

Blood Concentrations-Pediatric PatientsBlood Concentrations-Pediatric Patients(n=78)(n=78)

0.03% Tacrolimus Ointment0.03% Tacrolimus Ointment

0%

20%

40%

60%

80%

100%

<0.5 0.5 - <1 1 - <2 2 - <5 > 5

Highest Observed TacrolimusWhole Blood Concentration (ng/mL)

% P

atie

nts

87%

12%1% 0% 0%

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Phase III US StudiesPhase III US Studies

Distribution of TacrolimusDistribution of TacrolimusBlood ConcentrationBlood Concentration

0.1% Tacrolimus Ointment0.1% Tacrolimus Ointment

0%

20%

40%

60%

80%

100%

<0.5 0.5 - <1 1 - <2 2 - <5 > 5

Highest Observed TacrolimusWhole Blood Concentration (ng/mL)

% P

atie

nts

Adults Pediatric

(n=193) (n=30)

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Mean Blood Levels (ng/mL)Mean Blood Levels (ng/mL) 0.1% Tacrolimus Ointment0.1% Tacrolimus Ointment

VisitVisit

Week 1Week 1

Week 12Week 12

Month 6Month 6

Month 12 Month 12

AdultAdult

MeanMean

0.330.33

0.200.20

--

--

NN

176176

119119

--

--

PediatricPediatric

MeanMean

0.160.16

0.100.10

--

--

NN

2626

1818

--

--

AdultAdult

MeanMean

0.470.47

0.310.31

0.340.34

0.280.28

NN

282282

251251

219219

6262

USUS EuropeEurope

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Population Pharmacokinetic Population Pharmacokinetic AnalysisAnalysis

462 patients in US clinical trials462 patients in US clinical trials Average % BSA affected at baseline = 43%Average % BSA affected at baseline = 43% Estimation of “typical” exposureEstimation of “typical” exposure Nonlinear Mixed Effect Modeling (NONMEM)Nonlinear Mixed Effect Modeling (NONMEM)

Steady state concentrationSteady state concentration0.25 ng/mL0.25 ng/mL

AUCAUC0-24 hours0-24 hours 6 ng•hr/mL6 ng•hr/mL

Similar in pediatricsSimilar in pediatrics

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HypotheticalHypotheticalWorst Case Systemic Exposure in Atopic Worst Case Systemic Exposure in Atopic

Dermatitis PatientsDermatitis Patients European adult pharmacokinetic studyEuropean adult pharmacokinetic study

– Application of 0.1% tacrolimus ointmentApplication of 0.1% tacrolimus ointment– AUCAUC0-24 hours0-24 hours = 20 ng•hr/mL = 20 ng•hr/mL

Model assumptionsModel assumptions(contrary to clinical evidence)(contrary to clinical evidence)– lesions don’t heallesions don’t heal– % affected BSA doesn’t decrease% affected BSA doesn’t decrease– quantifiable blood concentration for prolonged quantifiable blood concentration for prolonged

periodsperiods

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Typical AD Patient

Hypothetical Worst Case AD Patient

Transplant Patient

Transplant Patient with PTLD

Mice with Lymphoma

Cumulative AUC 122 days

732

1,410

55,144

79,208

65,392

Comparative AUC forComparative AUC forTacrolimus Blood LevelsTacrolimus Blood Levels

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Relative toAD Patients:

Transplant Recipients

Transplant Recipients with PTLD

Mice with Lymphoma

Hypothetical“Worst”

Case

39x

56x

46x

“Typical”Case

75x

108x

89x

Relative Cumulative Systemic Exposure of TacrolimusRelative Cumulative Systemic Exposure of TacrolimusBased on Blood LevelsBased on Blood Levels

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Clinical PharmacologyClinical PharmacologyConclusionConclusion

Minimal systemic absorptionMinimal systemic absorption– Most patients do not have quantifiable levelsMost patients do not have quantifiable levels

No systemic accumulationNo systemic accumulation– Levels are transientLevels are transient

Pediatric patients have a lower frequency Pediatric patients have a lower frequency of detectable blood levels and lower of detectable blood levels and lower average levels than adultsaverage levels than adults

Large safety margin in comparison to Large safety margin in comparison to immunosuppressed transplant patients or immunosuppressed transplant patients or micemice