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Page 1: Enhanced Cancer Vaccine Effectiveness with NKTR-214, a … · Enhanced Cancer Vaccine Effectiveness with NKTR-214, a CD122-Biased Cytokine Jonathan Zalevsky SVP, Biology and Preclinical

Enhanced Cancer Vaccine Effectiveness with NKTR-214, a CD122-Biased Cytokine

Jonathan ZalevskySVP, Biology and Preclinical Development

Nektar Therapeutics

SMI Cancer Vaccines, September 2017

Page 2: Enhanced Cancer Vaccine Effectiveness with NKTR-214, a … · Enhanced Cancer Vaccine Effectiveness with NKTR-214, a CD122-Biased Cytokine Jonathan Zalevsky SVP, Biology and Preclinical

Biopharmaceutical company leveraging polymer conjugation technologies to develop new therapies in multiple disease areas

Strong heritage of partnership with top biopharma companies

~ 450 employees• R&D Center and Headquarters

in San Francisco, CA

• Pharmaceutical Development & Manufacturing in Huntsville, AL

• R&D support in Hyderabad, India

2

Nektar Therapeutics

San Francisco, CA

Huntsville, AL

Hyderabad, India

100,000-sq.ft.State-of-the-Art

R&D Center

114,000-sq.ft.Manufacturing

Facility

88,000-sq.ft.R&D Support

Facility

Page 3: Enhanced Cancer Vaccine Effectiveness with NKTR-214, a … · Enhanced Cancer Vaccine Effectiveness with NKTR-214, a CD122-Biased Cytokine Jonathan Zalevsky SVP, Biology and Preclinical

Wet macular degeneration

2004

2003

Acromegaly

Evolution of Nektar‘s Polymer Conjugation Technology

3

Hepatitis C

2001

Hepatitis C Chronic kidney disease anemia

2007 2014

2002

Neutropenia

2008

Crohn’s

Opioid inducedconstipation

Hemophilia A

R&D

NKTR-214

NKTR-255

NKTR-262

2015

Small molecule

Biologics

Large Molecule Half-life Extension

Concentration in Diseased Tissue

Small Molecule Compartmental

Distribution

Bias Receptor Activity

NKTR-358

NKTR-181

Page 4: Enhanced Cancer Vaccine Effectiveness with NKTR-214, a … · Enhanced Cancer Vaccine Effectiveness with NKTR-214, a CD122-Biased Cytokine Jonathan Zalevsky SVP, Biology and Preclinical

Overview

An introduction to IO research at Nektar

NKTR-214• CD122 biased agonist based on PEG-conjugation of IL-2

Combination of NKTR-262 + pMEL-1 Melanoma Vaccine • pMEL-1 cell expansion and functional activation in the tumor microenvironment

4

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The Immunity Cycle and Multiple Points of Intervention for I-O Therapies

5

4. Trafficking of T cells to tumor

5. Infiltration of T cells

into tumors

6. Recognition of cancer cells

by T cells

7. Killing of cancer cells1. Release of

cancer cell antigens

2. Cancer antigen presentation

3. Priming and

activation

Source:Oncology Meets Immunology: The Cancer-Immunity CycleChen and MellmanImmunity, Volume 39, Issue 1, 1 - 10

Page 6: Enhanced Cancer Vaccine Effectiveness with NKTR-214, a … · Enhanced Cancer Vaccine Effectiveness with NKTR-214, a CD122-Biased Cytokine Jonathan Zalevsky SVP, Biology and Preclinical

4. Trafficking of T cells to tumor (CTLs)

5. Infiltration of T cells into tumors (CTLs, endothelial

cells)

6. Recognition of cancer cells

by t cells (CTLs, cancer

cells)

7. Killing of cancer cells (immune and cancer

cells)

1. Release of cancer cell antigens (cancer

cell death)

2. Cancer antigen

presentation (dendritic

cells/APCs)

3. Priming and activation

(APCs & T cells)

Nektar’s Immuno-Oncology Strategy to Create Therapies that Cover the Immunity Cycle

6

Therapies need to be

accessible as medicines

Target as many steps as possible in the cycle with as few therapies as

possible

Page 7: Enhanced Cancer Vaccine Effectiveness with NKTR-214, a … · Enhanced Cancer Vaccine Effectiveness with NKTR-214, a CD122-Biased Cytokine Jonathan Zalevsky SVP, Biology and Preclinical

3. Priming and activation

(APCs & T cells)

6. Recognition of cancer cells

by t cells (CTLs, cancer

cells)

5. Infiltration of T cells into tumors (CTLs, endothelial

cells)

7. Killing of cancer cells (immune and cancer

cells)

1. Release of cancer cell antigens (cancer

cell death)

2. Cancer antigen

presentation (dendritic

cells/APCs)

Nektar’s Immuno-Oncology Strategy to Create Therapies that Cover the Immunity Cycle

7

4. Trafficking of T cells to tumor (CTLs)

Therapies need to be

accessible as medicines

Target as many steps as possible in the cycle with as few therapies as

possible

NKTR-214 (CD122 Agonist)

Prime, Proliferate, Activate & Increase Tumor-Infiltrating

Lymphocytes (TILs), Increase PD-1 expression

Page 8: Enhanced Cancer Vaccine Effectiveness with NKTR-214, a … · Enhanced Cancer Vaccine Effectiveness with NKTR-214, a CD122-Biased Cytokine Jonathan Zalevsky SVP, Biology and Preclinical

NKTR-214: Biasing Action to CD 122, or IL-2R Beta, to Stimulate T-Cell Production

Biases signaling to favor the CD122 Receptor (IL-2Rβγ complex)

Eliminates over-activation of IL-2 pathway that results in serious safety issues

Achieves antibody-like dosing schedule in outpatient setting

8

CTLs

CD8+ T-Cellsand NK Cells

NKTR-214

Stimulates ImmuneResponse to Kill

Tumor Cells

CD4+ Regulatory T-Cells

Tregs

Down-Regulates Proliferation of CD8+ T-cells

and Suppresses Immune Response

Page 9: Enhanced Cancer Vaccine Effectiveness with NKTR-214, a … · Enhanced Cancer Vaccine Effectiveness with NKTR-214, a CD122-Biased Cytokine Jonathan Zalevsky SVP, Biology and Preclinical

NKTR-214 Is A CD122-biased Cytokine, Designed To Improve Efficacy And Mitigate Toxicity of the IL-2 Pathway

9

IL-2: purple IL-2Rα: blueIL-2Rβ: cyan IL-2Rγ: green

Structural model of IL-2docked with IL-2Rαβγ

IL-2

IL-2Rα(CD25)

IL-2Rβ(CD122)

IL-2Rγ(CD132) IL-2 cytokine core

• rhIL-2, same amino acid sequence as clinically validated molecule (aldesleukin)

High molecular weight hydrolyzable polymers located at strategic sites

NKTR-214

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NKTR-214: Biased Signaling And Prodrug Design To Improve Risk/Benefit Profile

10

NKTR-214 (essentially inactive)

% P

hosp

ho-S

TAT5

Charych, D., et al. AACR 2013, Abstract #482

Page 11: Enhanced Cancer Vaccine Effectiveness with NKTR-214, a … · Enhanced Cancer Vaccine Effectiveness with NKTR-214, a CD122-Biased Cytokine Jonathan Zalevsky SVP, Biology and Preclinical

NKTR-214: Biased Signaling And Prodrug Design To Improve Risk/Benefit Profile

11

Active Species(Biased signaling, increased potency

with fewer PEGs)

NKTR-214 (essentially

inactive)

% P

hosp

ho-S

TAT5

Charych, D., et al. AACR 2013, Abstract #482

Page 12: Enhanced Cancer Vaccine Effectiveness with NKTR-214, a … · Enhanced Cancer Vaccine Effectiveness with NKTR-214, a CD122-Biased Cytokine Jonathan Zalevsky SVP, Biology and Preclinical

NKTR-214: Biased Signaling And Prodrug Design To Improve Risk/Benefit Profile

12

Active Species(Biased signaling, increased potency

with fewer PEGs)

NKTR-214 (essentially

inactive)

% P

hosp

ho-S

TAT5

Charych, D., et al. AACR 2013, Abstract #482

Page 13: Enhanced Cancer Vaccine Effectiveness with NKTR-214, a … · Enhanced Cancer Vaccine Effectiveness with NKTR-214, a CD122-Biased Cytokine Jonathan Zalevsky SVP, Biology and Preclinical

NKTR-214: Biased Signaling And Prodrug Design To Improve Risk/Benefit Profile

13

Active Species(Biased signaling, increased potency with fewer PEGs)

NKTR-214 (essentially

inactive)

% P

hosp

ho-S

TAT5

Charych, D., et al. AACR 2013, Abstract #482

Page 14: Enhanced Cancer Vaccine Effectiveness with NKTR-214, a … · Enhanced Cancer Vaccine Effectiveness with NKTR-214, a CD122-Biased Cytokine Jonathan Zalevsky SVP, Biology and Preclinical

NKTR-214 Mechanism of Action Delivers a Controlled and Biased Signal to the IL-2 Pathway

14

pSTAT5 is a biomarker of IL-2 receptor target engagement. pSTAT5= signal transducer and activator of transcription 5 p=phosphorylated (activated)

C57BL/6 mice were treated with either one dose of NKTR-214 (blue) or aldesleukin (red); blood samples were collected at various time points post-dose. pSTAT5 in peripheral blood CD3+ T cells was assessed using flow cytometry. Top graph is an inset showing the 0-4 hour time period. Bottom

graph shows the full 10 day time course of the experiment. Histograms on right depict pSTAT5 MFI for IL-2 (red) and NKTR-214 (blue)

In mice, a single dose of NKTR-214 gradually builds and sustains pSTAT5 levels through seven days post-dose. In contrast, IL-2 produces a rapid burst of pSTAT that declines four hours post-dose.

Charych, D., et al. AACR 2013, Abstract #482

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B16F10 melanoma, C57Bl/6 mice; N=9-12/groupNKTR-214, 2mg/kg i.v. q9dx3; Aldesleukin, 3mg/kg i.p. bidx5, 2 cycles*, p<0.05, ANOVA with Tukey’s post-test (left) or Log-Rank (right) w.r.t. vehicle‡, p<0.05, Student’s T-test (left) or Log-Rank (right) w.r.t. Aldesleukin

NKTR-214 Increases The Quality And Quantity Of The T-cell Response in Mice

> 400-fold increased ratio of CD8 to Treg cells

15

0 2 4 6 8 10 12 14 16

0

200

400

600

800

1000

1200

1400

1600

Days

*

*

treatment duration

Mouse melanoma model

Tota

l C

D8

/ Tre

g ra

tio

CD8/Treg ratio

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NKTR-214 Selectively Grows T Cells, NK Cells in Tumor Microenvironment in Cancer Patients

NKTR-214 drives immune activation in the tumor • Increase in total T cells, NK and CD8 T

cells • No increase in Tregs• Increase in PD-1 positive CD8 T cells• Increase in newly proliferating CD8 T cells• Activation and expression of anti-tumor

genes• Change in T cell clonality in the tumor

16

Fold change expressed as Week 3 / predoseShown are results from N=10 patients

Analysis of T cell Populations in Tumor

0

10

20

30

40

CD8 Tregs

1.6

29.8

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3. Priming and activation

(APCs & T cells)

6. Recognition of cancer cells

by t cells (CTLs, cancer

cells)

5. Infiltration of T cells into tumors (CTLs, endothelial

cells)

7. Killing of cancer cells (immune and cancer

cells)

1. Release of cancer cell antigens (cancer

cell death)

2. Cancer antigen

presentation (dendritic

cells/APCs)

Nektar’s Immuno-Oncology Strategy to Create Therapies that Cover the Immunity Cycle

17

4. Trafficking of T cells to tumor (CTLs)NKTR-214 (CD122 Agonist)

Prime, Proliferate, Activate & Increase Tumor-Infiltrating

Lymphocytes (TILs), Increase PD-1 expression

CheckpointInhibitors

Page 18: Enhanced Cancer Vaccine Effectiveness with NKTR-214, a … · Enhanced Cancer Vaccine Effectiveness with NKTR-214, a CD122-Biased Cytokine Jonathan Zalevsky SVP, Biology and Preclinical

NKTR-214: Combination With Anti-PD-1 Consistently Produces Durable Responses in Mice

NKTR-214 + anti-PD-1 is superior to anti-CTLA-4 + anti-PD-1

18

0 20 40 60 800

25

50

75

100

Days

*NKTR-214 + anti-PD-1

anti-CTLA-4 + anti-PD-1

0 20 40 60 80 1000

25

50

75

100

Days

*

*

VehicleAnti-CTLA-4Anti PD-1

NKTR-214

Anti CTLA-4 + Anti PD-1

NKTR-214 + Anti PD-1

CT26 colon carcinoma, Balb/c mice, N=10/groupAnti-CTLA-4, 100µg i.p., twice-weekly; Anti-PD-1, 200µg i.p., twice weeklyNKTR-214, 0.8mg/kg i.v. q9dx3*, p<0.05, ANOVA with Tukey’s post-test (left) or Log-Rank (right) w.r.t. vehicle

Long-term survivalColon Cancer Model

Long-term survivalBreast Cancer Model

EMT6 breast carcinoma, Balb/c mice, N=10/groupAnti-CTLA-4, 100µg i.p., twice-weekly; Anti-PD-1, 200µg i.p., twice weekly NKTR-214, 0.8mg/kg i.v. q9dx3*, p<0.05, ANOVA with Tukey’s post-test (left) or Log-Rank (right) w.r.t. vehicle

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NKTR-214 Drives Greater T-cell Expansion And T-Cell Clonality in Mice

19

Vehicle

aPD-1

aCTLA-4

NKTR-214

aCTLA4 + aPD-1 NKTR-214 + aCTLA4

NKTR-214 + aPD-1

ImmunoSeq Data(in collaboration with Adaptive Biotechnologies)

0 5 10 15 20 25 30 35

0

200

400

600

800

1000

1200

1400

1600

1800

Days

Mea

n Tu

mor

Vol

ume

(mm

3 )

0 5 10 15 20 25 30 35

0

200

400

600

800

1000

1200

1400

1600

Days

NKTR-214 + aPD-1

NKTR-214 + aCTLA4

aCTLA4 + aPD-1

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Harnessing the IL-2 Pathway the Right Way to Increase TILs

20

Prodrug design to enable safe, outpatient dosing Q2w or Q3w

Active cytokine species bias signaling through the heterodimeric IL-2 receptor pathway (IL-2Rβγ)

Biased and sustained signaling to preferentially activate and expand effector CD8+ T and NK cells over Tregs in the tumor microenvironment

Prodrug (inactive)

Currently in multiple clinical trials• NKTR-214 + checkpoint

‒ Combo with nivolumab: 14 tumor types‒ Combo with pembrolizumab in 2 tumors‒ Combo with atezolizumab in 2 tumors

• Other NKTR-214 combination trials to begin 2018

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3. Priming and activation

(APCs & T cells)

6. Recognition of cancer cells

by t cells (CTLs, cancer

cells)

5. Infiltration of T cells into tumors (CTLs, endothelial

cells)

7. Killing of cancer cells (immune and cancer

cells)

1. Release of cancer cell antigens (cancer

cell death)

2. Cancer antigen

presentation (dendritic

cells/APCs)

Nektar’s Immuno-Oncology Strategy to Create Therapies that Cover the Immunity Cycle

21

4. Trafficking of T cells to tumor (CTLs)

Therapies need to be

accessible as medicines

Target as many steps as possible in the cycle with as few therapies as

possible

NKTR-214 (CD122 Agonist)

Prime, Proliferate, Activate & Increase Tumor-Infiltrating

Lymphocytes (TILs), Increase PD-1 expression

Vaccine Model

Provide Antigens Activate Dendritic

Cell Response

CheckpointInhibitors

Page 22: Enhanced Cancer Vaccine Effectiveness with NKTR-214, a … · Enhanced Cancer Vaccine Effectiveness with NKTR-214, a CD122-Biased Cytokine Jonathan Zalevsky SVP, Biology and Preclinical

Melanoma Vaccine Mouse Model to Study NKTR-214

Pmel-1 cancer vaccine developed by Overwijk and Rosenberg• Pmel-1 cells adoptive transfer + peptide

vaccination for killing B16F10 tumors• IL-2 is essential for driving anti-tumor pMEL-1

response

Pmel-1 are genetically marked killer T cells• Easy to track in tumor and blood• Responsive to anti-melanoma vaccine• Kill melanoma cells

Use model to study effect of NKTR-214

22

Vaccine Vaccine + IL-2

Overwijk et al. JEM 2003

o Adoptive transfer of gp100-specific Pmel-1 cells

o Gp100 peptide (50 ug/mouse)-L-tyr (adjuvant)

o anti –CD40 (50 ug/mouse)

o TLR-7 agonist (Imiquimod- 5 mice/pack)

o Recombinant IL-2 (100,000 IU X 5 doses_ Day 0, D1 and D2) or

NKTR-214 (0.2mg/kg)

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Evaluation of NKTR-214 in Pmel-1 Vaccine Model

23

1. No treatment

2. Aldesleukin

3. NKTR-214

4. Vaccine

5. Vaccine + Aldesleukin (IL-2)

6. Vaccine + NKTR-214

Pmel-1 Cell Transfer

Vaccine = gp100 peptide + anti-CD40 + TLR-7 agonist

Aldesleukin (IL-2) – 100,00 IU b.i.d_D0,D1,D2_q8d

NKTR-214- 0.2 mg/kg_q8d

Collaboration with Meenu Sharma, Willem

Overwijk Laboratory, MD Anderson Cancer Center

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NKTR-214 More Effective that Aldesleukin to Delay Tumor Growth in Mouse Melanoma Vaccine Model

24M. Sharma, Willem Overwijk Laboratory, MD Anderson Cancer Center

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NKTR-214 Promotes Massive Pmel-1 Cell Expansion After Vaccination

25

NKTR-214-vaccine significantly enhanced Pmel-1 T cell response as compared to Aldesleukin-vaccine

p= <0.001

M. Sharma, Willem Overwijk Laboratory, MD Anderson Cancer Center

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D3 D5 D7 D100

200000

400000

600000 Untreated

Vaccine + NKTR-214 Vaccine + Aldesleukin Vaccine

***

Days after vaccination

Num

ber o

f Thy

1.1+

CD8

T c

ells

/ gr

am o

f tum

orNKTR-214 Vaccine Combination Superior to Aldesleukin for Pmel-1 CD8 T Cell Expansion in Tumor and Spleen

26

Tumor

D3 D5 D7 D100

500000

1000000

1500000

2000000

No Tx

Vaccine + NKTR-214 Vaccine + Aldesleukin Vaccine

Days after vaccination

Num

ber o

f Thy

1.1+

CD8

T c

ells

/Spl

een ***Untreated

Vaccine + NKTR-214 Vaccine + Aldesleukin Vaccine

***

Untreated

Vaccine + NKTR-214 Vaccine + Aldesleukin Vaccine

***Spleen

M. Sharma, Willem Overwijk Laboratory, MD Anderson Cancer Center

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NKTR-214 Promotes Higher Pmel-1/Treg Ratio than Aldesleukin in Tumor and Spleen

27

0 1000 2000 3000 4000

Day 10

Day 7

Day 5

Day 3

Pmel-1/Tregs (Tumor)

No TreatmentVaccineVaccine + AldesleukinVaccine + NKTR-214

0 50 100 150

Day 10

Day 7

Day 5

Day 3

Pmel-1/Tregs (Spleen)

ure 5

B

M. Sharma, Willem Overwijk Laboratory, MD Anderson Cancer Center

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NKTR-214 Preferentially Drives Pmel-1 Proliferation

28

As compared to Vaccine alone and aldesleukin-vaccine combination, NKTR-vaccine treatment

significantly maintained higher proliferation of Pmel-1 T cells and lower proliferation of Tregs in

tumor as well as in spleen

Day 7

M. Sharma, Willem Overwijk Laboratory, MD Anderson Cancer Center

Page 29: Enhanced Cancer Vaccine Effectiveness with NKTR-214, a … · Enhanced Cancer Vaccine Effectiveness with NKTR-214, a CD122-Biased Cytokine Jonathan Zalevsky SVP, Biology and Preclinical

NKTR-214 Preferentially Promotes Pmel-1 Survival

In tumor, addition of NKTR-214 to vaccine reduced annexin V expression on Pmel-1 and enhanced it on Tregs though no significant change was exhibited in Aldesleukin-Vaccine treatment group

In contrast to tumor, Annexin V expression in spleen was reduced on both Pmel-1 T cells and Tregs, in NKTR-vaccine group as compared to vaccine alone

29

Day 7

M. Sharma, Willem Overwijk Laboratory, MD Anderson Cancer Center

Page 30: Enhanced Cancer Vaccine Effectiveness with NKTR-214, a … · Enhanced Cancer Vaccine Effectiveness with NKTR-214, a CD122-Biased Cytokine Jonathan Zalevsky SVP, Biology and Preclinical

Summary and Conclusions

NKTR-214 is a CD122-biased agonist that effectively activates the IL-2 receptor pathway in preclinical and clinical settings

Addition of NKTR-214 to peptide vaccine drives enhanced Pmel-1 T cells in tumor as well as in spleen

• NKTR-214 is better than Aldesleukin in stably maintaining high CD8+ (Pmel-1 cells) and low Treg numbers in tumor

At the peak of Pmel-1 response on day 7, number of Tregs dramatically reduced in tumor of NKTR-vaccine treated group

Relative expression of Ki67 and Annexin V indicated that NKTR-vaccine treatment supports proliferation and survival of Pmel-1 T cells in tumor as well as in spleen

Reduced proliferation and moderately enhanced apoptosis in intratumoral Tregs, seem to contribute to observed low number of Tregs in tumor of NKTR-vaccine treated mice

30