Ph I l ti f fil ibPhase I evaluation of carfilzomib (PR-171) in hematological ( ) g

malignanciesA K i h S O A O’C M liA. Keith Stewart, Owen A. O’Conner, Melissa

Alsina, Suzanne Trudel, Andre Goy, and Robert Z Orlowskiand Robert Z. Orlowski

ASCO Annual MeetingASCO Annual MeetingJune, 2007

Clinical Rationale for PR-171Clinical Rationale for PR-171

P t i hibiti h b lid t d• Proteasome inhibition has been validated as a therapeutic strategy

• Bortezomib therapeutic hypothesis– Proteasome inhibition of 65 - 80% is proven to be

effective and safe– Full recovery of proteasome activity may be required

between doses to reduce toxicitybetween doses to reduce toxicity

• PR-171 therapeutic hypothesisI t i d t i d t i hibiti b– Intensive and sustained proteasome inhibition can be tolerated and will improve efficacy

2

Proteasome Inhibitor ComparisonBiochemical mechanism and selectivity

PR-171 BortezomibIrreversible

(keto-epoxide tetrapeptide)Slowly reversible

(boronic acid dipeptide)Highly selective for chymotrypsin-like Inhibits both chymotrypsin-like and caspase-g y y yp

active site within the proteasomey yp p

like activities of the proteasome

Highly selective for proteasome N-terminal threonine active sites

Cross reactivity with serine proteases

20S proteasome particle β-subunit ring

IC50s (nM)

N terminal threonine active sites

αβ

β5*

pPR-171 Bortezomib

Chymotrypsin-like 6 7β

βα

β1β2* *

like

Caspase-like 2400 74

Trypsin-like 3600 4200

3

ββ yp

* Three distinct N-terminal threonine protease active sites

PR-171 Pre-Clinical Summary

Proteasome activity recovers with t1/2~24 hr( t th i )

Cellular

(new proteasome synthesis)

One-hour treatments (mimicking in vivo exposure) are more cytotoxic with PR 171 than with bortezomibactivities more cytotoxic with PR-171 than with bortezomib

PR-171 is cytotoxic to primary MM patient cells and b t ib i t t ll libortezomib-resistant cells lines

Daily dosing regimens with PR-171 are well tolerated

In vivo Proteasome inhibition at MTD is greater in most tissues with PR-171 (>80%) than with bortezomib (65-75%)properties

( ) ( )

Daily dosing schedules with PR-171 (e.g., QDx2) are most efficacious than day 1, 4 schedule in xenograft

4models

PR-171 (Carfilzomib) Phase 1 Studies• Two parallel studies in hematologic malignancies

with two dose scheduleswith two dose schedules• Multiple myeloma (MM), non Hodgkin’s lymphoma (NHL),

Waldenstrom’s macroglobinemia (WM), Hodgkin’s disease (HD) • Relapse or refractory >2 prior treatments• Prior bortezomib allowed, < grade 2 neuropathy allowed

M difi d Fib i (3 3) d i• Modified Fibonacci (3+3) design

• Primary objectives: Safety, establish maximum t l bl dtolerable dose

• Secondary objectives: Anti-tumor efficacy, y j ypharmacokinetics, pharmacodynamics

• Subjects treated to intolerable toxicity or5

Subjects treated to intolerable toxicity or progressive disease

Phase 1 Dose Schedules

0

D1 D5 PX-171-001D140

bitio

n • QDx5; 9 day rest• 2 week cycle

C ti i80

ome

inhi

b • Continuous suppression of proteasome activity

80

1 2

prot

easo

D2 D8 D9D10

D15 D16 PX-171-002QD 2 kl f 3

D28

% p 0 • QDx2 weekly for 3

weeks; 12 day rest• 4 week cycle80

Time (weeks)1 2 3 4

• Prevent full recovery of proteasome between doses

Effi i

80

6

Efficacious proteasome

inhibition threshold

PX-171-001 (QDx5) Dose Escalation( )September 2005-April 2007

Disease type ResponsesNHL/ MM/Cohort N NHL/ HD

MM/WD PR MR SD

1.2-8.4 mg/m2 15 11 4 3 NHL11 mg/m2 3 2 1 1 MM 1 MCL*15 mg/m2 3 1 2 1 WM20 mg/m2 5 3 2 1 MM20 mg/m2 5 3 2 1 MM

Total 27 18 9 1 2 4*Dose escalatedDose escalated

Objective responses in 3/5 MM/WM patients at ≥ 11 mg/m2

7

PX-171-002 (QDx2) Dose Escalation(Q )September 2005-April 2007

Disease type ResponsesNHL/Cohort N NHL/HD MM/WD PR MR SD

1.2-8.4 mg/m2 16 10 64* (1 MM,

3 NHL)g

3 NHL)11 mg/m2 4 2 2 1 MM*15 mg/m2 3 1 2 1 MM*15 mg/m 3 1 2 1 MM20 mg/m2 3 1 2 1 MM27 mg/m2 6 1 5 2 MM 1 MM 1 MM

Total 37 16 21 4 1 6*Dose escalated

8Objective responses in 5/9 MM patients at ≥ 15 mg/m2

Clinical MM Activity Summary• Responses characterized by rapid decline in M-protein• Responses in heavily pre-treated patientsp y p p

– Average of 5 prior therapies – Bortezomib, thalidomide/lenalidomide, transplant failures

• Duration of response 55+ 288+ days• Duration of response 55+ - 288+ days– Onset of response d15 to d49

2-01-005 (15 mg/m2)

200225

200225

2-01-012 (MM; 27 mg/m2)800 6

100125150175200

100125150175200

20 mg/m2

KappaLightChain

UrinaryM-Protein(mg/24 hr) 300

400500600700

3

4

5

SerumM-protein

(g/dL)

-300 -200 -100 0 100 200 3000

255075

0255075(mg/L) (mg/24 hr)

-900 -3000

100200300

0

1

2

-200 -100 0 100

(g/dL)

9

Study Day Study Day

R d PX 171 001 (QD 5)Responders – PX-171-001 (QDx5)

Diagnosis(dose cohort)

ORDOT

(days)# prior ther. Vel Thal Rev SCT

1-04-005 MM (11 mg/m2 ) PR 78 5 + + - -

1-05-003 WM (15 mg/m2) MR 75 7 - - - -

1-04-008 MM (20 mg/m2) MR 45 10 ++ + + ++

• 4 SD patients (1 MM, 1 T-cell NHL, 2 MCL) with duration on therapy 112 to 223 days py y

• Responding patients have been discontinued due to “t t t f ti ”

10“treatment fatigue”

Responders PX 171 002 (QDx2)Responders – PX-171-002 (QDx2)

Diagnosis(dose cohort)

ORTTP

(days)# prior ther. Vel Thal Rev SCT

2-01-005 MM (15 →20 mg/m2) PR 288+ 5 - - - +

2-01-008 MM (20 mg/m2) PR 233 6 + - - +

2-01-009 MM (27 mg/m2) PR 134+ 6 ++ + + -

2-01-011 MM (27 mg/m2) MR 134 4 - + ++ +

2-01-012 MM (27→ 20 mg/m2) PR 100+ 4 + + - +

• 6 SD patients (2 MM, 1 T cell NHL, 2 MCL) with duration on therapy 189+ to 413 days

11

Pharmacokinetics and Pharmacodynamics

• Preclinical studies in rats and monkeys show that carfilzomib is cleared from plasma within minutescarfilzomib is cleared from plasma within minutes

• Serum concentrations approach the limits of detection within 1 hourdetection within 1 hour

• Pharmacokinetic parameters unlikely to guide selection of doseselection of dose

• Pharmacodynamics of proteasome activity provides a more biologically relevant characterizationa more biologically relevant characterization– Assay measures chymotrypsin-like proteasome activity– Whole blood and mononuclear cells examined

12

Pharmacodynamics: Proteasome Inhibition and Clinical Acti itInhibition and Clinical Activity

Whole Blood PDWhole Blood PD(PX-171-001 and PX-171-002)

100110

y ol)

Assays performedone hour after first

dose of cycle 1

708090

100

e ac

tivity

e co

ntro

NHL/HD

MM/WM

30405060

teas

ome

pred

ose MM/WM

non-responders

MM/WM

1 100 300

1020

Prot

(% o

f MM/WMresponders(PR/MR)

≥80% proteasome inhibition achieved at doses above 15 mg/m2

Dose (mg/m2)

13

≥80% proteasome inhibition achieved at doses above 15 mg/m2

Proteasome Recovery in PBMC –PX-171-002 (QDx2)

Red blood cell

100

120

ity trol

)

PBMC

dosing

60

80

100

ome

activ

dose

con

t

2-01-0072-01-0082-02-016

20

40

Prot

easo

% o

f pre

-d Average

QDx2 schedule

0 1 2 3 4 5 6 7 8 90

Day

P(%

0 1 2 3 4 5 6 7 8 9

QDx2 schedule20 mg/m2

Day

Red blood cell proteasome activity fails to recover

between Day 2 and Day 8 due t i ibl h i

PBMC proteasome activity recovers between Day 2 and

Day 8 due to new t th i

14

to irreversible mechanism proteasome synthesis

Safety and Tolerability: Phase 1Safety and Tolerability: Phase 1 • Majority of AEs are Grade 1 or 2Majority of AEs are Grade 1 or 2

– Gastrointestinal (nausea, vomiting, diarrhea)– Systemic (fatigue, pyrexia)Systemic (fatigue, pyrexia)– Neurologic (headache)– Respiratory (cough dyspnea)Respiratory (cough, dyspnea)

• Grade 2/3 reversible ↑ creatinine following 1st dose in four patients heralding rapid decreases in M-spikep g p p– 3/5 MM patients at 27 mg/m2, 1/6 MM patients at 20 mg/m2

– Event is self-limiting if drug is held, effect does not occur on rechallenge, subsequent treatment well tolerated

• Reversible Grade 3/4 thrombocytopenia in patients enrolled with Grade 2 thrombocytopenia

15

enrolled with Grade 2 thrombocytopenia• Painful peripheral neuropathy has not been reported

DLT d MTD PX 1 1 001 (QD )DLT and MTD – PX-171-001 (QDx5)

Dose level Cycle/Day Event Comment

20 mg/m2 Cycle 1/ Day 4 Febrile neutropeniaResolved, continued on

study

Cycle 1/ Not resolved20 mg/m2 Cycle 1/ Day 3 ThrombocytopeniaNot resolved,

discontinued (PD)

• DLTs to date are hematologic• MTD not established• Study continues to enroll at 15 mg/m2

16

DLT and MTD PX 171 002 (QDx2)DLT and MTD – PX-171-002 (QDx2)

Dose level Cycle/Day Event Comment

27 mg/m2 Cycle 1/ D 8 ThrombocytopeniaResolved, continued on

t d27 mg/m Day 8 Thrombocytopenia study

27 mg/m2 Cycle 1/ Day 2 HypoxiaResolved, rapid response and continued on studyDay 2 and continued on study

20 mg/m2 Cycle 1/Day 2Acute Renal

Failure Recovering

• DLTs to date are hematologic, hypoxia and ↑Cr• 20 mg/m2 established as a “tolerable dose”• 27 mg/m2 necessitates further management of first

17dose effect

Carfilzomib Phase I Summaryy• Carfilzomib is a novel irreversible inhibitor selective for the

chymotrypsin-like active site of the proteasome y yp p• Carfilzomib promotes >80% proteasome inhibition in blood• Dose limiting toxicitiesDose limiting toxicities

– Myelosuppression: cyclic reversible thrombocytopenia and neutropenia

– A “first dose effect” has occurred at doses >20 mg/m2 and heralds rapid decline in M-protein

• Objective responses have been observed at doses of carfilzomib ranging from 11 mg/m2 to 27 mg/m2

R id t f ( 1 th)– Rapid onset of response (1 year

Carfilzomib Development Planp

• Carfilzomib will be further investigated in bothCarfilzomib will be further investigated in both hematologic malignancies and solid tumors

– Ongoing expansion to treat NHL patients

• Phase 2 studies are beginning in refractory MMPhase 2 studies are beginning in refractory MM and relapsed MM patients through the Multiple Myeloma Research ConsortiumMyeloma Research Consortium

• A Phase 1b study is planned for solid tumors

19

Creatinine (1st week, QDx2)

3 5

4.0

4.5

Doses

20 mg/m2

2.0

2.5

3.0

3.5

2-01-0072-01-0082-02-0212-02-016

Patient # Disease Response Doses withheld

MMMM PRFL

MCLatin

ine

(mg/

dL)

1 2 3 4 5 6 7 8 9ne

0.0

0.5

1.0

1.5 2-01-0162-01-0172-06-005

MMMM #3MM

Cre

a

Bas

elin

Day

2 5

3.027 mg/m2

1.5

2.0

2.5

2-01-0092-01-0112-01-012

Patient # Disease ResponseDoses

withheld

MM PR #2, 3, 4MM MRMM PR #3, 4ni

ne (m

g/dL

)

0.0

0.5

1.02-02-0182-02-0172-06-004

MMMCLMMC

reat

in

20

1 2 3 4 5 6 7 8 9

Bas

elin

e

0.0

Day

Creatinine Plots (QDx2 27mg/m2)Creatinine Plots (QDx2, 27mg/m )2-01-009 (MM, 27 mg/m2) (PR) 2-01-011 (MM, 27 mg/m2) (MR)

2

3 Dosecycle 1 cycle 2

(mg/

dL)

1.5

2.0

2.5 Dosecycle 1 cycle 2

(mg/

dL)

0

1

0

Cre

atin

ine

0 0

0.5

1.0

Cre

atin

ine

B0 0

0 10 20 30 40 50Day

B0.0

0 10 20 30 40 50day

2-01-012 (MM, 27→20 mg/m2) (PR)( , g ) ( )

2

3 1000cycle 1 (27) cycle 2 (20)

mg/

dL)

1

Cre

atin

ine

(m

21B

0 00 10 20 30 40 50

day