Poster # 588 Enhanced Efficacy of Immune Modulators with...
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Poster # 588 B-004 AACR 10/29/17 Enhanced Efficacy of Immune Modulators with Albumin Binding Domains (ABD) Haomin Huang, Keneneshia Haenssen, Anil Bhate, Supriya Sanglikar, John Baradei, Shan Liu, Senthil Kumar, Zihao Cui, Richard Hampton, Robert Kramer and John Cini | Sonnet Biotherapeutics, 1 Duncan Drive, Cranbury, NJ 08512, USA Small (<100Kd) recombinant therapeutic proteins penetrate better into solid tumors but exhibit shorter circulation half-life (mins/hour vs. 21 days) when compared to IgG’s. Methods to improve serum half-life for these small MW therapeutic proteins include conjugation to polyethylene glycol (ie., PEG: eg., Peg-Intron, NKT-214) or formulations on the surface of, or within, nanoparticles. Albumin has also been successfully exploited as a carrier for small therapeutic proteins. Examples include the genetic fusion of Interferon to albumin (Albuferon) and the use of a multivalent albumin binding antibody fragment that has the capacity to bind serum albumin and also neutralize TNFa (Ozoralizumab). A potential advantage to the use of albumin as a drug carrier is that albumin is known to accumulate in inflamed and angiogenic tissues such as the tumor microenvironment, and may thus provide a means of passive targeting to the tumor. Sonnet BioTherapeutics, using a XOMA phage library, has developed a fully human single chain variable antibody (scFv) construct with demonstrated high binding affinity to serum albumin across species (mouse, human & cynomolgus monkey) and retains the benefits of FcRn mediated recycling of albumin for extending serum half-life. This scFv albumin binding domain (ABD) has been utilized to create several different genetic fusion constructs with various small molecular weight therapeutic proteins (e.g., recombinant interleukins such as IL12, and scFv’s against relevant immune-oncology targets, ie., TGFb). In mouse models, these ABD constructs have extended serum half-lives, improved tumor accumulation and enhanced efficacy compared to their respective naked recombinant therapeutic protein. This poster summarizes the discovery of our scFv-ABD and preliminary studies with four different therapeutic scFv-ABD constructs demonstrating the broad utility of this approach. INTRODUCTION SONNET BioTherapeutics Platform 1. Single-Chain Antibody (ScFv) Based • Flexibility for multiple mechanisms of action • Dual affinity targets enhance specific tumor delivery • Small size enhanced tumor penetration • Plug-and-play versatility for target selection can inhibit and/or stimulate 2. Albumin Binding Domain (ABD); scFv binds Human Serum Albumin (HSA) • Tumor delivery – HSA is elevated in tumors & inflamed tissues • Enhanced pharmacokinetics - T 1/2 from minutes to days 3. Recombinant Human (Hu) Proteins (Interleukins; scFv vs. TGFb) • ABD – hu Interleukins (e.g. IL12 or IL15) • ABD – 2X hu Interleukins (e.g. IL15 –ABD- IL12) • ABD – scFv (e.g. TGFβ) (Bi or Tri Targeting Arms) VH VL VL VH scFv-B VH VL scFv Albumin Target #1 Target #2 VH VL VL VH scFv-B scFv Albumin Target #1 or ABD scFv Albumin VH VL VL VH Interleukin or VH VL VL VH scFv-B Interleukin #1 scFv Albumin scFv TGFb scFv Albumin Interleukin #2 Figure 1 ABD Bio-Activity Selection Criteria to Ensure Increase in PK Binding to Human & Cyno Serum Albumin kD ~20 - 60 nM Binding to Mouse Serum Albumin kD ~10 - 30 nM Binding at low pH 5.5 & neutral pH7.2 for human, mouse albumin No competition with FcRn binding to serum albumin. In-vitro studies with ABD showed cell recycling with the FcRn hence should extend pK in-vivo (see Fig below) Binds Albumin in serum by immune-precipitation Human serum stability at 37C for 7-14 Days Immunogenicity tested by Antitope computer analysis ABD scFv Albumin XOMA (Library 47) full human scFv phage library was used to screen for a scFv by solid & soluBon panning against HSA, MSA and h/mTGFβ 1, 2 & 3. ABD selecBon was based on meeBng all of the above criteria. AnB Albumin Binding Domain (ABD) A10M3 is a scFv: VH3/VL1, Tm ~60C, MW 26KD, pI 7.1 AnB TGFβ selecBon based on blocking TGF inducing of: Tregs proliferaBon, TGFàSMAD2 PO4, EMT & MigraBon AnB TGFβ (4D9M) is a scFv: VH3/VL1, Tm ~62C, MW 26KD, pI 5.3 Figure 2 ABD significantly reduces lysosomal degradation shown in yellow 60 minutes post addition of complexes Yellow color indicates colocalization of 4D9M with lamp1 (lysosome) Separation of green and red indicates lack of colocalization ABD Binding to Albumin/FcRn in Live Cells Escape Lysosomal Degradation Untreated Lamp1 DAPI 4D9M 4D9M Lamp1 DAPI 4D9M-ABD 4D9M-mono Lamp1 DAPI 4D9M-ABD-4D9M 4D9M-bi Lamp1 DAPI Materials Needed: - 4D9M is a (anti-TGFβ ScFv ) - 4D9M -ABD - 4D9M- ABD- 4D9M - Anti-Human CD107a (LAMP-1) [red channel] - Anti-6X His tag® antibody [green channel] - DAPI Blue [blue channel] - HUVECs and accompanying components (Lonza) - Human Serum Albumin Green/Red Yellow Figure 3 His-tagged Evaluation of anti-TGFβ 4D9M scFv & anti-TGFβ 4D9M-ABD Tumor Accumulation In vivo Proof of Concept 50kD 25 kD 0.5 4 12 24 0.5 4 12 24 0.5 4 12 24 hours Western blot analysis of Mouse 4T1 (TGFβ positive) tumor (@ 100 mm 3 ) extracts from mice terminated at 0.5, 4, 12 and 24 hours post IV injection with 100 ug/mouse of: ABD, antiTGFβ or antiTGFβ -ABD. Results show accumulation and retention of ABD in the tumor • ABD - Present at 0.5 hours, peaks at 4 hours and detectable through 24 hours. • Anti-TGF svFv - Present at 0.5 hours then declines at 4 hours and undetectable at 12 and 24 hours. • Anti-TGF svFv-ABD – is present at 0.5 hours. and detectable through 24 hours. ABD accumulates in the tumors 24 hrs+ and without ABD, the scFv enters tumor but diffuses out after 4 hrs. Data supports ABD POC for the platform’s ability to enhance penetration/accumulation & retention within the tumor. VH VL VL VH AB scFv-B VH VL AB D ABD anJTGF no ABD anJTGF-ABD VL VH scFv-B Figure 4 PK Half-Life T 1/2 of ABD Constructs IL12 & IL15 The aim of this study is to demonstrate in mice, the pharmacokinetic (PK) behavior of naked IL12 & IL15 compared to the same fusion proteins linked to albumin binding domain (ABD) IL12-ABD & IL15-ABD. Method: 8 mice C57B/ TP, Age 9.5 weeks dose IV, sacrificed @ 5, 15, 30 mins, 1, 2, 4, 8, 24 & 48 hrs. Serum tested by ELISA 1.00000 10.00000 100.00000 1,000.00000 10,000.00000 100,000.00000 1,000,000.00000 10,000,000.00000 0 5 10 15 20 25 30 Protein ConcentraBon ( pg/ml ) Time ( Hours) IL15 WT IL15-A10M3 t 1/2 β ~ 7.0 hrs t 1/2 β =0.6 hrs VL VH scFv-B VH VL * IL15 PK in Mice ~ 0.5 hrs 2012 PLoS ONE 7(2): 1.00 10.00 100.00 1,000.00 10,000.00 100,000.00 1,000,000.00 10,000,000.00 0 5 10 15 20 25 30 Protein ConcentraJon ( pg/ml ) Time ( Hours) IL12-A10M3 IL12 WT VL VH scFv-B t 1/2 β = 9.5 hrs t 1/2 β = 2.5 hrs* * IL12 PK in Mice ~ 3 hrs J. Immunol. 164, 839–847 Fusion to ABD increased the plasma half-life of IL12 > 4x and IL15 >10X IL12 MW = 70 kd vs IL15 MW=13 kd Figure 5 IL15 scFv Albumin 0 5 10 15 20 25 30 35 40 PBS 1 ug 10 ug 25 ug % InhibiJon % Tumor InhibiJon Day 11 IL15-ABD 3 Doses Effect of IL-15 ABD in B16F10 on Tumor Growth and on Lymphocyte Populations in Spleens and Tumors Established tumor 100 mm 3 then Dosing @ 0, 2, 4 days IL15-ABD showed reduction in TV and a 5-7 fold increase in the tumor NK cells (FACS data next slide) Figure 6 Effect of IL-15 ABD Treatment on Tumor Infiltration Lymphocyte Populations CD49b+ CD122+ CD49b+CD27+ IL-15 ABD 25ug Vehicle Control CD49b+ CD122+ CD49b+CD27+ Analysis of infiltrating lymphocyte populations by FACS show increases in NK cell populations within the tumor of IL15-ABD treated mice resulting in a reduction of tumor growth. NK cells IL2/IL15R beta Mature NK cells NK cells IL2/IL15R beta Mature NK cells ↑ 5 fold ↑ 7 fold ↑7 fold Figure 7 IL12 scFv Albumin 0 500 1000 1500 2000 2500 3000 G1: Vehicle G2: IL12 (3µ g) G3: IL12-ABD (4.5µ g) G4: IL12 (10µ g) G5: IL12-ABD (15µ g) G6: IL12 (20µ g) G7: IL12-ABD (30µ g) *** *** *** *** * P=0.0109 P=0.0027 P=0.0818 Treatment Groups Final Tumor Volume (mm 3 ) All black color stars are compared to Vehicle group by one-way ANOVA *<0.05 **<0.01 ***<0.001 Blue color represents P-values by unpaired T-test Day 10 Post Single Dose (@ 100 mm 3 ) of IL-12 or IL-12-ABD in B16F10 Melanoma Equal molar concentration IL12 G2=G3 G4=G5 G6=G7 IL12 Equal molar concentration of IL12 show that IL12-ABD is more potent than IL12 Figure 8 Tumor Weight Spleen Weight IFN- γ Placebo IL12-ABD (4.5ug/mouse) IL12 (3ug/mouse) 0.0 0.1 0.2 0.3 0.4 Grams 0 2 4 6 0 500 1000 1500 2000 2500 Days p g /m l Placebo IL12-ABD (4.5ug) IL12 (3ug) 0 2 4 6 0 10 20 30 Days Post Treatment Initiation Body W eight (g) Placebo IL12-ABD (4.5ug) IL12 (3ug) IL12-ABD demonstrated a greater suppression of tumor growth and a corresponding increase in immune activation as shown by the increase in spleen weight and a transient increase in serum IFN without an effect on mouse bodyweight compared to the molar equivalent dose of recombinant IL12. Comparison of Pharmacodynamic Effects of IL12-ABD & IL12 @ 5 Days After Single Dose B16-F10 Tumor-bearing (100 mm 3 ) Equal molar doses of IL12 = 3ug IL12-ABD 4.5ug = IL12 3ug Placebo IL12-ABD (4.5ug/mouse) IL12 (3ug/mouse) 0.0 0.1 0.2 Grams Figure 9 WBC Day 3 IL12-ABD (1.3 µg) IL12 (30 µg) Tumor bearing control 0 2 4 6 8 10 x10 3 cells WBC Day 7 IL12-ABD (1.3 µg) IL12 (30 µg) Tumor bearing control 0 2 4 6 8 10 x10 3 cells IL12-ABD (1.3 µg) IL12 (30 µg) Tumor bearing control Tumor free control 0 2 4 6 8 10 50 100 150 pg/ml IL12-ABD (1.3 µg) IL12 (30 µg) Tumor bearing control Tumor free control 0.0 0.5 1.0 1.5 pg/ml Comparison of Hematopoietic Effects of IL12-ABD (1.3ug) & IL12 (30ug) at 3 & 7 Days After Single Dose B16-F10 Tumor-bearing (100 mm 3 ) IFN γ IFN γ Day 3 Day 7 IL12-ABD (1.3 ug) and recombinant IL12 (30ug) produced comparable transient reducJons in hematologic parameters that returned to control values by day 7. However, IL12-ABD produced a significantly greater transient increase in serum IFN γ on day 3, that was comparable to recombinant IL12 IFN γserum values by day 7. Normal range Normal range Normal range Figure 11 IL12 IL15 scFv Albumin Sonnet Tri-Specific Construct Enhanced Biologic Activity: IL12 : ↑ IL15 alpha receptor, IFN, NK/Tcells, TH1 & ↓ Treg IL15 : ↑ IL12 beta 1 receptor, NK cells & ↓ CD8 memory loss Figure 12 CONCLUSIONS 1. A novel 26 Kd scFv antibody (ABD) that binds mouse, cynomolgus monkey and human serum albumin has been identified, and is being developed, as a platform for enhancing the pharmacokinetics and tumor targeting of small molecular weight therapeutic proteins (Figures 1-3). 2. We demonstrate increased retention of an anti-TGFβ-scFv-ABD construct in 4T1 tumors in mice (Figure 4) and up to a 10-fold enhancement of the serum half-life in mice of recombinant IL12 or IL15 when fused to the scFv-ABD construct (Figure 5). 3. Dose dependent increases in anti-tumor activity were demonstrated with either IL15-ABD or IL12- ABD constructs (Figures 6-8), producing a corresponding increase in tumor infiltrating NK cells for IL15-ABD (Figures 6 & 7). FACs studies on cell infiltrates following IL12-ABD treatment are planned. 4. Molar equivalent doses of IL12-ABD were significantly more efficacious (3-30 fold) than naked recombinant IL12 vs. the B16F10 mouse melanoma model (Figure 8 & 10) and produced a corresponding increase in immune response as reflected by spleen weight and serum IFN, which was transient and had no effect on mouse body weight (Figure 9). 5. A first-in-class dual targeting tri-specific cytokine construct (IL15-ABD-IL12) demonstrated slightly enhanced in vitro cellular activity compared to either recombinant IL12 or IL15 (Figure 13), that translated to superior in vivo activity compared to IL12-ABD vs. the B16F10 mouse melanoma model (Figure 14). Sonnet wishes to acknowledge Drs. Olesia Buiakova & Yan Xu (InVivoTek, NJ) for their excellent work involving all animal studies, IL12-ABD vs. IL15-ABD-IL12 @ Equal Molar Concentration to the IL12 Single Dose (@ 100 mm 3 ) Day 10 Tumor Volume (n=8) IL12 scFv Albumin IL15 scFv Albumin IL12 The molar equivalent dose of IL12 used in the IL12-ABD-IL15 (6ug) construct was more effecJve than IL12- ABD (5ug) vs the established B16F10 sc mouse melanoma tumor model. Other in-vivo studies show that free IL12 (5ug) + IL15 (1ug) is less than 50% as effecJve as IL15-ABD-IL12 (6ug)(not shown). 0 500 1000 1500 Final Tumor Volume (mm 3 ) Vehicle IL12-ABD (5ug) IL15-ABD-IL12 (6ug) Figure 14 www.sonnetbio.com [email protected] Evaluation of Single Dose (SD) IL12-ABD (1.3 ug) vs. IL12 (30ug) in B16F10 Melanoma (established @100 mm 3 , n=8) Tumor Volume 2857 1996.94 1002.18 Dose Recombinant IL12 (1ug) & IL12-ABD (1.3ug) are molar equivalent & have the same bioacJvity in-vitro (data not shown). However, IL12-ABD was ~ 30+ fold more potent than recombinant IL12 in vivo as reflected by a single dose of IL12-ABD at 1.3 ug producing a comparable reducJon in tumor volume as a single 30 ug dose of recombinant IL12 on days 1-8 post treatment. The duraJon of benefit was longer for IL12-ABD (day 10). Hematologic changes and serum IFN γ are reported in Figure 11. 0 2 4 6 8 10 0 500 1000 1500 2000 2500 3000 Days Tum or Volum e (m m 3 ) Placebo IL12-ABD (1.3 ug, SD) IL12 (30ug, SD) = Molar 0.9 ug of [IL12] Figure 10 Assessment of IL-12 & IL15 Cell Based Activity for the IL15-ABD-IL12 IL15 10 -10 10 -5 10 0 10 5 10000 15000 20000 25000 [Agonist], pM RLU hIL-12 (R&D Systems) hIL15RA-ABD-mIL12 batch: H-C-02/03 IFN-γ release (IL-12) Lymphoblast proliferaJon assay (IL-12) IL12 0 100 200 300 400 750 150 30 6 1.2 0 hIFNg (pg/ml) Dose (pM) hIL12 (R&D) hIL15RA-ABD-mIL12 batch: H-C-02/03 CTLL-2 cytotoxic T lymphocytes are able to proliferate in response to either human or mouse IL-15 CTLL-2 mCTLL-2 IL15-ABD-IL12 cell based assays show bio-activity in the tri-specific construct 0.1 1 10 100 1000 0.5 1.0 1.5 2.0 2.5 [Agonist], pM O.D. (490nm) hIL-15 (R&D System s) hIL15-ABD-mIL12 hIL15 (R&D) hIL15-ABD- mIL12 log(agoni st) vs. response Best-fit values Bottom 0.404 0.4036 Top 1.947 1.937 LogEC50 1.261 1.01 HillSlope 4.968 4.694 EC50 18.26 10.23 CTLL-2 proliferaJon assay (IL-15) hIL-12 (R&D Systems) hIL15RA-ABD-mIL12 batch: H-C-02/03 log(agonist) vs. response Best-fit values Bottom 12982 12867 Top 21276 21297 LogEC50 -0.5968 -0.5351 HillSlope 0.8736 0.9478 EC50 0.2530 0.2917 IL12 AcBvity based on proliferaBon & IFN secreBon Figure 13
Transcript of Poster # 588 Enhanced Efficacy of Immune Modulators with...
Poster # 588
B-004
AACR 10/29/17
Enhanced Efficacy of Immune Modulators with Albumin Binding Domains (ABD)Haomin Huang, Keneneshia Haenssen, Anil Bhate, Supriya Sanglikar, John Baradei, Shan Liu, Senthil Kumar, Zihao Cui, Richard Hampton, Robert Kramer and John Cini | Sonnet Biotherapeutics, 1 Duncan Drive, Cranbury, NJ 08512, USA
Small (<100Kd) recombinant therapeutic proteins penetrate better into solid tumors but exhibit shorter circulation half-life (mins/hour vs. 21 days) when compared to IgG’s. Methods to improve serum half-life for these small MW therapeutic proteins include conjugation to polyethylene glycol (ie., PEG: eg., Peg-Intron, NKT-214) or formulations on the surface of, or within, nanoparticles. Albumin has also been successfully exploited as a carrier for small therapeutic proteins. Examples include the genetic fusion of Interferon to albumin (Albuferon) and the use of a multivalent albumin binding antibody fragment that has the capacity to bind serum albumin and also neutralize TNFa (Ozoralizumab). A potential advantage to the use of albumin as a drug carrier is that albumin is known to accumulate in inflamed and angiogenic tissues such as the tumor microenvironment, and may thus provide a means of passive targeting to the tumor.
Sonnet BioTherapeutics, using a XOMA phage library, has developed a fully human single chain variable antibody (scFv) construct with demonstrated high binding affinity to serum albumin across species (mouse, human & cynomolgus monkey) and retains the benefits of FcRn mediated recycling of albumin for extending serum half-life. This scFv albumin binding domain (ABD) has been utilized to create several different genetic fusion constructs with various small molecular weight therapeutic proteins (e.g., recombinant interleukins such as IL12, and scFv’s against relevant immune-oncology targets, ie., TGFb). In mouse models, these ABD constructs have extended serum half-lives, improved tumor accumulation and enhanced efficacy compared to their respective naked recombinant therapeutic protein. This poster summarizes the discovery of our scFv-ABD and preliminary studies with four different therapeutic scFv-ABD constructs demonstrating the broad utility of this approach.
INTRODUCTION
SONNET BioTherapeutics Platform
1. Single-Chain Antibody (ScFv) Based
• Flexibility for multiple mechanisms of action • Dual affinity targets enhance specific tumor delivery • Small size enhanced tumor penetration • Plug-and-play versatility for target selection can inhibit and/or stimulate
2. Albumin Binding Domain (ABD); scFv binds Human Serum Albumin (HSA)
• Tumor delivery – HSA is elevated in tumors & inflamed tissues • Enhanced pharmacokinetics - T1/2 from minutes to days
3. Recombinant Human (Hu) Proteins (Interleukins; scFv vs. TGFb)
• ABD – hu Interleukins (e.g. IL12 or IL15) • ABD – 2X hu Interleukins (e.g. IL15 –ABD- IL12) • ABD – scFv (e.g. TGFβ)
(Bi or Tri Targeting Arms)
VH
VLVL
VH
ABD
scFv-A scFv-B
VH
VLVL
VH
ABD
scFv-A scFv-B
scFv Albumin Target #1
Target #2
VH
VLVL
VH
ABD
scFv-A scFv-BscFv Albumin Target #1
or
ABDscFvAlbumin
VH
VLVL
VH
ABD
scFv-A scFv-B
Interleukin
or VH
VLVL
VH
ABD
scFv-A scFv-BInterleukin #1 scFv Albumin scFv TGFb scFv
Albumin
Interleukin #2
Figure 1
ABD Bio-Activity Selection Criteria to Ensure Increase in PK
Binding to Human & Cyno Serum Albumin kD ~20 - 60 nM
Binding to Mouse Serum Albumin kD ~10 - 30 nM
Binding at low pH 5.5 & neutral pH7.2 for human, mouse albumin
No competition with FcRn binding to serum albumin. In-vitro studies with ABD showed cell recycling with the FcRn hence should extend pK in-vivo (see Fig below)
Binds Albumin in serum by immune-precipitation
Human serum stability at 37C for 7-14 Days
Immunogenicity tested by Antitope computer analysis
ABDscFvAlbumin
XOMA(Library47)fullhumanscFvphagelibrarywasusedtoscreenforascFvbysolid&soluBonpanningagainstHSA,MSAandh/mTGFβ1,2&3.
ABDselecBonwasbasedonmeeBngalloftheabovecriteria.
AnBAlbuminBindingDomain(ABD)A10M3isascFv:VH3/VL1,Tm~60C,MW26KD,pI7.1
AnBTGFβselecBonbasedonblockingTGFinducingof:TregsproliferaBon,TGFàSMAD2PO4,EMT&MigraBon
AnBTGFβ(4D9M)isascFv:VH3/VL1,Tm~62C,MW26KD,pI5.3 Figure 2
ABD significantly reduces lysosomal degradation shown in yellow
60 minutes post addition of complexes
Yellow color indicates colocalization of 4D9M with lamp1 (lysosome)
Separation of green and red indicates lack of colocalization
ABD Binding to Albumin/FcRn in Live Cells Escape Lysosomal Degradation
Untreated
Lamp1DAPI
4D9M
4D9MLamp1DAPI
4D9M-ABD
4D9M-monoLamp1DAPI
4D9M-ABD-4D9M
4D9M-biLamp1DAPI
Materials Needed: - 4D9M is a (anti-TGFβ ScFv) - 4D9M -ABD - 4D9M- ABD- 4D9M - Anti-Human CD107a (LAMP-1) [red channel] - Anti-6X His tag® antibody [green channel] - DAPI Blue [blue channel] - HUVECs and accompanying components (Lonza) - Human Serum Albumin
Green/RedYellow
Figure 3
His-tagged
Evaluation of anti-TGFβ 4D9M scFv & anti-TGFβ 4D9M-ABD Tumor Accumulation In vivo Proof of Concept
50kD
25 kD
0.54 12 24 0.5 4 12 24 0.5 4 12 24 hours
Western blot analysis of Mouse 4T1 (TGFβ positive) tumor (@ 100 mm3) extracts from mice terminated at
0.5, 4, 12 and 24 hours post IV injection with 100 ug/mouse of: ABD, antiTGFβ or antiTGFβ-ABD.
Results show accumulation and retention of ABD in the tumor • ABD - Present at 0.5 hours, peaks at 4 hours and detectable through 24 hours. • Anti-TGF svFv - Present at 0.5 hours then declines at 4 hours and undetectable at 12 and 24 hours. • Anti-TGF svFv-ABD – is present at 0.5 hours. and detectable through 24 hours. ABD accumulates in the tumors 24 hrs+ and without ABD, the scFv enters tumor but diffuses out after 4 hrs.
Data supports ABD POC for the platform’s ability to enhance penetration/accumulation & retention within the tumor.
VH
VLVL
VH
ABD
scFv-A scFv-B
VHVL
VLVH
ABDscFv-A
scFv-B
VH
VLVL
VH
ABD
scFv-A scFv-B
ABDABD anJTGFnoABD anJTGF-ABD
VH
VL VL
VH
ABD
scFv-AscFv-B
Figure 4
PK Half-Life T1/2 of ABD Constructs IL12 & IL15
The aim of this study is to demonstrate in mice, the pharmacokinetic (PK) behavior of naked IL12 & IL15 compared to the same fusion proteins linked to albumin binding domain (ABD) IL12-ABD & IL15-ABD. Method: 8 mice C57B/ TP, Age 9.5 weeks dose IV, sacrificed @ 5, 15, 30 mins, 1, 2, 4, 8, 24 & 48 hrs. Serum tested by ELISA
1.00000
10.00000
100.00000
1,000.00000
10,000.00000
100,000.00000
1,000,000.00000
10,000,000.00000
0 5 10 15 20 25 30
ProteinCo
ncen
traB
on(pg
/ml)
Time(Hours)
IL15WT IL15-A10M3
t1/2β~7.0hrst1/2β=0.6hrs
VH
VLVL
VH
ABD
scFv-A scFv-B
VH
VLVL
VH
ABD
scFv-A scFv-B
*IL15PKinMice~0.5hrs2012PLoSONE7(2):
1.00
10.00
100.00
1,000.00
10,000.00
100,000.00
1,000,000.00
10,000,000.00
0 5 10 15 20 25 30
ProteinConcentraJ
on(pg/m
l)
Time(Hours)
IL12-A10M3 IL12WT
VH
VLVL
VH
ABD
scFv-A scFv-B
t1/2β=9.5hrs
t1/2β=2.5hrs*
*IL12PKinMice~3hrsJ.Immunol.164,839–847
Fusion to ABD increased the plasma half-life of IL12 > 4x and IL15 >10X IL12 MW = 70 kd vs IL15 MW=13 kd Figure 5
IL15 scFv Albumin
0510152025303540
PBS 1ug 10ug 25ug
%InhibiJo
n
%TumorInhibiJonDay11
IL15-ABD3Doses
Effect of IL-15 ABD in B16F10 on Tumor Growth and on Lymphocyte Populations in Spleens and Tumors
Established tumor 100 mm3 then Dosing @ 0, 2, 4 days
IL15-ABD showed reduction in TV and a 5-7 fold increase in the tumor NK cells (FACS data next slide) Figure 6
Effect of IL-15 ABD Treatment on Tumor Infiltration Lymphocyte Populations
CD49b+ CD122+ CD49b+CD27+
IL-15 ABD 25ug
Vehicle Control
CD49b+ CD122+ CD49b+CD27+
Analysis of infiltrating lymphocyte populations by FACS show increases in NK cell populations within the tumor of IL15-ABD treated mice resulting in a reduction of tumor growth.
NKcellsIL2/IL15Rbeta MatureNKcells
NKcells IL2/IL15Rbeta MatureNKcells
↑5fold↑7fold↑7fold
Figure 7
IL12 scFv Albumin
0
500
1000
1500
2000
2500
3000 G1: VehicleG2: IL12 (3µg)G3: IL12-ABD (4.5µg)G4: IL12 (10µg)G5: IL12-ABD (15µg)G6: IL12 (20µg)G7: IL12-ABD (30µg)
***
*********
*
P=0.0109
P=0.0027
P=0.0818
Treatment Groups
Fina
l Tum
or V
olum
e (m
m3 )
All black color stars are compared to Vehicle group by one-way ANOVA *<0.05 **<0.01 ***<0.001 Blue color represents P-values by unpaired T-test
Day 10 Post Single Dose (@ 100 mm3) of IL-12 or IL-12-ABD in B16F10 Melanoma
Equal molar concentration IL12
G2=G3 G4=G5 G6=G7
IL12
Equal molar concentration of IL12 show that IL12-ABD is more potent than IL12 Figure 8
TumorWeight SpleenWeight IFN-γ
0 2 4 60
500
1000
1500
2000
2500
PlaceboIL12-ABD (1.5 µg/mouse)IL12-ABD (4.5 µg/mouse)IL12 (1 µg/mouse)IL12 (3 µg/mouse)
Days
pg/ml
P l ac e b o
I L1 2 - A
BD
( 4 . 5u g / m
o u s e )
I L1 2 ( 3 u g / m
o u s e )0 . 0
0 . 1
0 . 2
0 . 3
0 . 4
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ms
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0
5 0 0
1 0 0 0
1 5 0 0
2 0 0 0
2 5 0 0
D a y s
pg/m
l
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I L 1 2 - A B D ( 4 . 5 u g )
I L 1 2 ( 3 u g )
0 2 4 6
0
1 0
2 0
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D a y s P o s t T r e a t m e n t I n i t i a t i o n
Bo
dy
We
igh
t (g
)
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I L 1 2 - A B D ( 4 . 5 u g )
I L 1 2 ( 3 u g )
IL12-ABD demonstrated a greater suppression of tumor growth and a corresponding increase in immune activation as shown by the increase in spleen weight and a transient increase in serum IFN without an effect on mouse bodyweight compared to the molar equivalent dose of recombinant IL12.
Comparison of Pharmacodynamic Effects of IL12-ABD & IL12 @ 5 Days After Single Dose B16-F10 Tumor-bearing (100 mm3)
Equal molar doses of IL12 = 3ug
IL12-ABD 4.5ug = IL12 3ug
Pl a
c e b o
I L1 2 - A
BD
( 4 . 5u g / m
o u s e )
I L1 2 ( 3 u g / m
o u s e )0 . 0
0 . 1
0 . 2
Gra
ms
Figure 9
WBCDay 3
IL12-A
BD (1.3 µg
)
IL12 (3
0 µg)
Tumor bea
ring co
ntrol
0
2
4
6
8
10
x103 ce
lls
WBCDay 7
IL12-A
BD (1.3 µg
)
IL12 (3
0 µg)
Tumor bea
ring co
ntrol
0
2
4
6
8
10
x103 ce
lls
IFN-γDay 3
IL12-ABD (1.3 µg)
IL12 (30 µg)
Tumor bearin
g control
Tumor free contro
l02468
1050
100
150
pg/m
l
IFN-γDay 7
IL12-ABD (1.3 µg)
IL12 (30 µg)
Tumor bearin
g control
Tumor free contro
l0.0
0.5
1.0
1.5
2.0
2.5
pg/m
l
Comparison of Hematopoietic Effects of IL12-ABD (1.3ug) & IL12 (30ug) at 3 & 7 Days After Single Dose B16-F10 Tumor-bearing (100 mm3)
IFNγIFNγDay3Day7
IL12-ABD(1.3ug)andrecombinantIL12(30ug)producedcomparabletransientreducJonsinhematologicparametersthatreturnedtocontrolvaluesbyday7.However,IL12-ABDproducedasignificantlygreatertransientincreaseinserumIFNγonday3,thatwascomparabletorecombinantIL12IFNγserumvaluesbyday7.
Normalrange
Normalrange
Normalrange
Figure 11
IL12
IL15 scFv Albumin
Sonnet Tri-Specific Construct
Enhanced Biologic Activity: IL12 : ↑ IL15 alpha receptor, IFN, NK/Tcells, TH1 & ↓ Treg IL15 : ↑ IL12 beta 1 receptor, NK cells & ↓ CD8 memory loss
Figure 12
CONCLUSIONS
1. A novel 26 Kd scFv antibody (ABD) that binds mouse, cynomolgus monkey and human serum albumin has been identified, and is being developed, as a platform for enhancing the pharmacokinetics and tumor targeting of small molecular weight therapeutic proteins (Figures 1-3).
2. We demonstrate increased retention of an anti-TGFβ-scFv-ABD construct in 4T1 tumors in mice (Figure 4) and up to a 10-fold enhancement of the serum half-life in mice of recombinant IL12 or IL15 when fused to the scFv-ABD construct (Figure 5).
3. Dose dependent increases in anti-tumor activity were demonstrated with either IL15-ABD or IL12-ABD constructs (Figures 6-8), producing a corresponding increase in tumor infiltrating NK cells for IL15-ABD (Figures 6 & 7). FACs studies on cell infiltrates following IL12-ABD treatment are planned.
4. Molar equivalent doses of IL12-ABD were significantly more efficacious (3-30 fold) than naked recombinant IL12 vs. the B16F10 mouse melanoma model (Figure 8 & 10) and produced a corresponding increase in immune response as reflected by spleen weight and serum IFN, which was transient and had no effect on mouse body weight (Figure 9).
5. A first-in-class dual targeting tri-specific cytokine construct (IL15-ABD-IL12) demonstrated slightly enhanced in vitro cellular activity compared to either recombinant IL12 or IL15 (Figure 13), that translated to superior in vivo activity compared to IL12-ABD vs. the B16F10 mouse melanoma model (Figure 14).
Sonnet wishes to acknowledge Drs. Olesia Buiakova & Yan Xu (InVivoTek, NJ) for their excellent work involving all animal studies,
IL12-ABD vs. IL15-ABD-IL12 @ Equal Molar Concentration to the IL12 Single Dose (@ 100 mm3) Day 10 Tumor Volume (n=8)
IL12 scFv Albumin
IL15 scFv Albumin
IL12
ThemolarequivalentdoseofIL12usedintheIL12-ABD-IL15(6ug)constructwasmoreeffecJvethanIL12-ABD(5ug)vstheestablishedB16F10scmousemelanomatumormodel.Otherin-vivostudiesshowthatfreeIL12(5ug)+IL15(1ug)islessthan50%aseffecJveasIL15-ABD-IL12(6ug)(notshown).
0
5 0 0
1 0 0 0
1 5 0 0
Fin
al
Tu
mo
r V
olu
me
(m
m3
)
V e h ic le
I L 1 2 - A B D ( 5 u g )
I L 1 5 - A B D - I L 1 2 ( 6 u g )
Figure 14
www.sonnetbio.com
Evaluation of Single Dose (SD) IL12-ABD (1.3 ug) vs. IL12 (30ug) in B16F10 Melanoma (established @100 mm3 , n=8)
TumorVolume
2857
1996.94
1002.18
Dose
RecombinantIL12(1ug)&IL12-ABD(1.3ug)aremolarequivalent&havethesamebioacJvityin-vitro(datanotshown).However,IL12-ABDwas~30+foldmorepotentthanrecombinantIL12invivoasreflectedbyasingledoseofIL12-ABDat1.3ugproducingacomparablereducJonintumorvolumeasasingle30ugdoseofrecombinantIL12ondays1-8posttreatment.TheduraJonofbenefitwaslongerforIL12-ABD(day10).HematologicchangesandserumIFNγarereportedinFigure11.
0 2 4 6 8 1 0
0
5 0 0
1 0 0 0
1 5 0 0
2 0 0 0
2 5 0 0
3 0 0 0
D a y s
Tu
mo
r V
olu
me
(m
m3
)
P l a c e b o
I L 1 2 - A B D ( 1 . 3 u g , S D )
I L 1 2 ( 3 0 u g , S D )
= Molar 0.9 ug of [IL12]
Figure 10
Assessment of IL-12 & IL15 Cell Based Activity for the IL15-ABD-IL12 IL15
1 0 -1 0 1 0 -5 1 0 0 1 0 5
1 0 0 0 0
1 5 0 0 0
2 0 0 0 0
2 5 0 0 0
S a m p le 3
[A g o n is t ] , p M
RL
U
h IL - 1 2 (R & D S y s te m s )
h IL 1 5 R A - A B D - m IL 1 2 b a tc h : H - C - 0 2 /0 3
IFN-γrelease(IL-12)LymphoblastproliferaJonassay(IL-12)
IL12
0
100
200
300
400
750 150 30 6 1.2 0
hIFN
g(pg/ml)
Dose(pM)
hIL12(R&D)
hIL15RA-ABD-mIL12batch:H-C-02/03
CTLL-2cytotoxicTlymphocytesareabletoproliferateinresponsetoeitherhumanormouseIL-15
CTLL-2mCTLL-2
IL15-ABD-IL12 cell based assays show bio-activity in the tri-specific construct
0 . 1 1 1 0 1 0 0 1 0 0 0
0 . 5
1 . 0
1 . 5
2 . 0
2 . 5
[ A g o n i s t ] , p M
O.D
. (49
0n
m)
h I L - 1 5 ( R & D S y s t e m s )
h I L 1 5 - A B D - m I L 1 2
hIL15 (R&D)
hIL15-ABD-mIL12 log(agoni
st) vs. response Best-fit values Bottom 0.404 0.4036 Top 1.947 1.937
LogEC50 1.261 1.01
HillSlope 4.968 4.694 EC50 18.26 10.23
CTLL-2proliferaJonassay(IL-15)
hIL-12 (R&D Systems)
hIL15RA-ABD-mIL12 batch: H-C-02/03
log(agonist) vs. response Best-fit values Bottom 12982 12867 Top 21276 21297 LogEC50 -0.5968 -0.5351 HillSlope 0.8736 0.9478 EC50 0.2530 0.2917
IL12AcBvitybasedonproliferaBon&IFNsecreBon
Figure 13
