Slide 1: NKTR-255: Accessing IL-15 Therapeutic Potential through Robust and Sustained Engagement of Innate and Adaptive Immunity
NKTR-255: Accessing IL-15 Therapeutic Potential through Robust and Sustained Engagement of Innate and Adaptive Immunity Peiwen Kuo Scientist, Research Biology Nektar Therapeutics ► August 31st, 2018 Emerging Immuno-Oncology Targets
Slide 2: The immunity cycle and multiple points of intervention for I-O therapies
The immunity cycle and multiple points of intervention for I-O therapies 4. Trafficking of T cells to tumor 3. Priming and 5. Infiltration activation of T cells into tumors 2. Cancer 6. antigen Recognition presentation of cancer cells by T cells 7. Killing of 1. Release of cancer cells cancer cell S
Slide 3: Nektar's immuno-oncology strategy to create therapies that cover the immunity cycle
Nektar’s immuno-oncology strategy to create therapies that cover the immunity cycle 4. Trafficking of T cells to tumor (CTLs) NKTR-214 (CD122 Agonist) 3. Priming and Prime, Proliferate, Activate & activation Target as (APCs & T Increase Tumor-Infiltrating 5.cells Infiltration of T into tumors many s
Slide 4: The potential of IL-15 in immuno-oncology
The potential of IL-15 in immuno-oncology ► IL-15 is a pleiotropic cytokine with roles in innate and adaptive immunity ► Identified by NCI as one of the most promising immuno-oncology agents ► Induces survival of CD8 central memory and stem cell memory cells ► Essential factor for NK development and
Slide 5: Binding to IL-15Rα is required to access the biological functions of IL-15
Binding to IL-15Rα is required to access the biological functions of IL-15 Three potential modes of interaction • Trans-presentation: IL-15 binds to IL-15Rα on one cell (eg. DC) then signals through Rβγ on a second cell (e.g. T-cell) • Cis-presentation: soluble IL-15 binds to IL-15Rα and Rβγ on th
Slide 6: The challenge to therapeutic use of IL-15
The challenge to therapeutic use of IL-15 ► IL-15 displays rapid clearance from plasma ► In vivo signaling activity is similarly short-lived Plasma concentration (ng/ml) 1000 100 %pSTAT5 10 STAT5 phosphorylation is an early and transient event in IL-15/IL-2 receptor signaling 1 0.1 0 24 48 72 96 Tim
Slide 7: NKTR-255 – polymer conjugated IL-15
NKTR-255 – polymer conjugated IL-15 ► Design Goals: Improve PK and PD to sustain IL-15 activity and achieve large pharmacodynamic effect without need for daily dosing Retain binding to IL-15Rα to maintain full spectrum of IL-15 biology No mutagenesis or complex to soluble IL-15Rα ► As a result
Slide 8: NKTR-255 retains affinity for IL-15Rα
NKTR-255 retains affinity for IL-15Rα IL-15 NKTR-255 Conjugate kon (M-1 s-1) koff (s-1) KD (pM) IL-15 7.88 x 106 1.33 x 10-4 16.2 NKTR-255 1.08 x 106 1.69 x 10-4 182 ► Many conjugates were screened for ability to bind IL-15Rα ► Conjugation chemistry parameters were carefully selected to arrive at an
Slide 9: NKTR-255 signaling is mediated via IL-15Rα
NKTR-255 signaling is mediated via IL-15Rα Wt IL-15 Whole blood + NKTR-255 % of pSTAT5+ in CD45+ gate IL-15Rα KO IL-15/IL-15Rα complex IL-15 NKTR-255 IL-15/IL-15Rα complex NKTR255 NKTR255 wt IL-15Rα wt NKTR255 IL-15Rα wt IL-15Rα IL-15Rα -/- IL-15Rα -/- NKTR255 IL-15Rα -/- Treatment IL-15 NKTR-255 IL
Slide 10: NKTR-255 drives IL-15-like signaling across species
NKTR-255 drives IL-15-like signaling across species Human CD4 T Cyno-monkey CD8 T % of pSTAT5+ population + IL15/NKTR-255 Mouse on sub-populations Whole Blood NK IL-15 NKTR-255 NK CD8 T CD4 T NK CD8 T CD4 T EC50 (ng/ml) EC50 (ng/ml) Human 0.48 1.5 1.6 Human 5.1 4.9 5.3 Cyno-monkey 0.24 2.6 4.0 Cyno-
Slide 11: NKTR-255 binds IL-15Rα to engage the IL-15 pathway
NKTR-255 binds IL-15Rα to engage the IL-15 pathway ► NKTR-255 retains IL-15Rα binding SPR data supports that binding to IL-15Rα is maintained, with an affinity that is ~10x weaker than IL-15 ► NKTR-255 binding to IL-15Rα is essential for its activity JAK/STAT signaling is abrogated in the absenc
Slide 12: NKTR-255: sustained PK and robust PD in rodents and non-human primates
NKTR-255: sustained PK and robust PD in rodents and non-human primates 12
Slide 13: NKTR-255 achieves sustained plasma exposure in mice, rats and NHP after single dose
NKTR-255 achieves sustained plasma exposure in mice, rats and NHP after single dose IL-15 and NKTR-255 PK in Mice NKTR-255 PK in Rats 10000 10000 ng/ml plasma conc. ng/ml plasma conc. 1000 1000 µg/kg 1000 (mean SD) (mean SD) 300 µg/kg 150 µg/kg 100 100 100 µg/kg 75 µg/kg 10 30 µg/kg 10 10 µg/kg 10 µ
Slide 14: NKTR-255 drives prolonged signaling and proliferation in NK cells and CD8 T cells in mice
NKTR-255 drives prolonged signaling and proliferation in NK cells and CD8 T cells in mice after a single dose NK cell count in blood CD4 T cell count in blood 10000 10000 0.3 mg/kg 1000 1000 0.03 mg/kg Cell expansion Vehicle 100 100 Predose 10 10 0 24 48 72 96 120 144 168 192 216 240 0 24 48 72 96 1
Slide 15: NKTR-255 expands CD8 and NK cells in vivo in NHPs
NKTR-255 expands CD8 and NK cells in vivo in NHPs (mean, n=3-4) (mean, n=3-4) cells/ l x109 cells/ l x109 CD8 and NK cell expansion detected at 0.01 mg/kg dose level (mean, n=3-4) (mean, n=3-4) (mean, n=3-4) %pSTAT5 %Ki67 %Ki67 NK cells Ki-67 and pSTAT5 induced at lowest dose level (0.001mg/kg). (me
Slide 16: Memory CD8 T cells are highly sensitive to NKTR-255, exhibiting robust expansion after a single dose in mice
Memory CD8 T cells are highly sensitive to NKTR-255, exhibiting robust expansion after a single dose in mice CD8 TcM 100 pre-dose vehicle 0.3 mg/kg cells/ul 10 0.03 mg/kg 1 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Days CD8 TNaive 100 10 1 cells/ul 0.1 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Days 16
Slide 17: NHP CD8 memory populations are sensitive to NKTR-255
NHP CD8 memory populations are sensitive to NKTR-255 Cynomolgus monkeys NKTR-255 IV dose response PD: blood stained memory markers (CD45RA, CD197, CD95) in CD8 parent gate. 17
Slide 18: NKTR-255 expands NK subpopulations in mice
NKTR-255 expands NK subpopulations in mice NK cells at all stages of maturation are highly responsive to NKTR-255 Terminal Effector NK Terminal Effector (CD11b+CD27+) High Effector (CD11b+CD27+) Most mature High cytokine secretion 10000 Activation tightly regulation Great effector function 1000 High
Slide 19: NKTR-255 expands NK subpopulations in mice
NKTR-255 expands NK subpopulations in mice NK cells at all stages of maturation are highly responsive to NKTR-255 Terminal Effector NK Terminal Effector (CD11b+CD27+) High Effector (CD11b+CD27+) Most mature High cytokine secretion 10000 Activation tightly regulation Great effector function 1000 High
Slide 20: NKTR-255 increases effector protein expression in expanded NK and CD8 T cells in mice
NKTR-255 increases effector protein expression in expanded NK and CD8 T cells in mice GzmB+ MFI (CD8) GzmB+ MFI CD16+ MFI 20
Slide 21: NKTR-255 increases levels of cytotoxic enzymes in NK and CD8 T cells in NHPs
NKTR-255 increases levels of cytotoxic enzymes in NK and CD8 T cells in NHPs Granzyme MFI in CD8 T cells Granzyme B MFI in NK cells GzmB MFI in CD8 GzmB MFI in CD8 GzmB MFI in CD8 GzmB MFI in NK cells GzmB MFI in NK cells GzmB MFI in NK cells 2000 2000 2000 50000 50000 50000 40000 40000 40000 1500 1
Slide 22: NKTR-255 enhances murine splenic NK cytotoxicity
NKTR-255 enhances murine splenic NK cytotoxicity Spleens harvested NKTR-255 at Day 1, 4, 6 Effector cells: NK cells isolated from spleens Co-culture Label cells with 7-AAD; at 12.5:1 Analyze lysis of target (E:T ratio) cells via flow cytometry Target cells: for 4 hr YAC-1 cells labeled with PKH26 40
Slide 23: NKTR-255 has extended PK and drives robust NK and CD8 T cell responses
NKTR-255 has extended PK and drives robust NK and CD8 T cell responses ► NKTR-255 exhibits substantially superior PK over conventional IL-15 • Prolonged plasma exposure in rodents (T1/2 ~14-18hrs) and NHP (T1/2 ~30hrs) vs IL-15 (T1/2 <1hr) ► CD8 T and NK cells are responsive to NKTR-255 stimulation
Slide 24: NKTR-255: engaging NK and CD8 T cells to boost single agent anti-tumor efficacy
NKTR-255: engaging NK and CD8 T cells to boost single agent anti-tumor efficacy 24
Slide 25: NKTR-255 driving IL-15 anti-cancer immunotherapy via NK and CD8 biology
NKTR-255 driving IL-15 anti-cancer immunotherapy via NK and CD8 biology NK cell biology CD8 cell biology • Activation balance among human NK subtypes • Supporting memory CD8 T cell longevity and function ‒ IL-15 is similarly potent to regulatory CD56bright ‒ IL-15 maintains Ag-specific effector
Slide 26: NKTR-255 enhances NK cell-dependent anti-tumor efficacy in CT26 lung metastasis model
NKTR-255 enhances NK cell-dependent anti-tumor efficacy in CT26 lung metastasis model Lung nodules growth inhibition Female Balb/c mice (6-8 weeks) **** 105 cells CT-26 i.v. ^^^^ Count lung nodules 100 #### 80 **** NKTR-255 0.03 mg/kg; q7dx2, i.v. ^^^^ NKTR-255 0.1 mg/kg; q7dx2, i.v. 60 D0 D1 D8 D 1
Slide 27: NKTR-255 inhibits spontaneous metastasis in the 4T1 model
NKTR-255 inhibits spontaneous metastasis in the 4T1 model Mean tumor volumes of 4T1 Number of spontaneous metastatic subcutaneous tumors on Day 21 colonies on Day 14 in lungs 26
Slide 28: Conclusion
Conclusion ► NKTR-255 overcomes many limitations of IL-15 Improved PK to allow infrequent administration Provides sustained IL-15 PD activity from a single dose Achieves full breadth of signaling profile as expected for IL-15 ► By design, NKTR-255 maintains binding affinity for IL-15Rα ► NKTR-