1. Download poster to your desktop2. Click play button below for audio3. Press forward arrow key to see poster

ICONIC IO-Naive

0

10

20

30

Fre

qu

en

cy

of

CD

45

RA

- C

D6

2L

+

(% o

f IC

OS

hi

CD

4 T

ce

lls)

**

Background: Inducible T cell Co-stimulator (ICOS) is a costimulatory molecule expressed primarily on T lymphocytes that is upregulated upon cell activation. Vopratelimab(vopra) is a novel investigational ICOS agonist antibody whose primary mechanism of action is the stimulation of primed CD4 T effector cells. Clinical responses in the Phase 1/2 ICONIC trial (NCT02904226) were associated with the emergence of ICOS hi CD4 T cells. In a separate study of PD-1/L1 monotherapy, this phenotype was not observed, suggesting ICOS hi CD4 T cell emergence in ICONIC was due to vopra. Ex vivo stimulation of antigen-primed ICOS hi CD4 T cells by soluble vopra demonstrated induction of a polyfunctional cytokine response. Previous studies have shown that sustained ICOS upregulation was associated with clinical benefit in subjects treated with anti-CTLA-4 inhibitors, with preclinical data confirming a role for ICOS signaling in enhancing anti-tumor activity. Vopra is currently being tested as a sequenced combination with ipilimumab (ipi) in the Phase 2 EMERGE trial (NCT03989362).

Methods: Assessment of phenotype and function of ICOS hi CD4 T cells was conducted using serial collections of peripheral blood mononuclear cells (PBMCs) from a subset of evaluable subjects in the ICONIC trial. A mouse syngeneic tumor model was developed to assess the kinetics of ICOS hi emergence as well as determine functionality and combination efficacy. Biological activity was assessed through ex vivo functional assays, with phenotypic assessments by flow cytometry-based profiling and genomic analysis.

Results: Phenotypic profiling of ICOS hi CD4 T cells by NanoString and flow cytometry demonstrated enrichment of subsets including Th1, T central memory phenotype (Tcm), and T follicular helper (Tfh), and ICOS hi CD4 T cells increased as a % of the CD4 compartment longitudinally. By transcriptional analysis, potent effector molecules, including perforin and granzyme, were significantly upregulated in isolated ICOS hi CD4 T cells relative to ICOS lo CD4 T cells from subjects. In a syngeneic tumor-bearing mouse system, ICOS hi CD4 T cells were induced in lymphoid organs following ipitreatment, with emergence detectable at day 3 and peaking at day 7 post-treatment, where up to 40% of CD4 T cells were ICOS hi. Relative to monotherapy, enhanced anti-tumor efficacy was observed in mice treated with combination ICOS agonist and ipilimumab.

Conclusion: Emergence of a peripheral ICOS hi CD4 T cell population correlates with response to vopra treatment and occurs independent of anti-PD-1 activity. Transcriptional and flow profiling of ICOS hi CD4 T cells further defined the phenotype as Th1, Tcm, and Tfh cells, which may contribute to observed clinical benefit. Treatment with ipi in combination with an ICOS agonist resulted in enhanced efficacy in mice, and follow-up studies exploring sequential dosing are ongoing.

Poster#

5536ICOS hi CD4 T cells emerging on vopratelimab treatment have Th1, central memory, and Tfh

characteristics that may contribute to durability of clinical responses

1 Jounce Therapeutics Inc, Cambridge, MA. USA

ABSTRACT RESULTS

• Emergence of a peripheral blood ICOS hi CD4 T cell population is

associated with durable responses to vopratelimab +/- nivolumab

• ICOS hi phenotype is induced in an antigen-specific manner through

stimulation of the T cell receptor, and vopratelimab is only active on primed

ICOS hi CD4 T cells

• The ICOS hi CD4 T cell population within peripheral blood of ICONIC

responders is comprised of Th1, Tcm, and Tfh subsets, which may be critical

for direct anti-tumor effects as well as durability of clinical responses

• Retrospective flow analysis of publicly available mass cytometry data

demonstrated ipilimumab or ipilimumab + nivolumab induced enrichment of a

robust Th1 but not Tcm or Tfh phenotypes within peripheral blood

• In a hCTLA-4 knock-in mouse model, preliminary assessment of anti-tumor

efficacy demonstrated added activity when scheduled dosing of an ICOS

agonist included administration following ICOS hi induction by ipilimumab

• In the ongoing EMERGE study, we are testing the hypothesis that addition

of ICOS agonist following IPI-induced ICOS hi emergence may enhance

clinical benefit

SUMMARY

Mechanism of Action

REFERENCES

Amanda Hanson, Abha Dhaneshwar, Heather Cohen, Yasmin Hashambhoy-Ramsay, Kristin O’Malley, Krithi Bala, Lara McGrath, Kristen Leone, Courtney Hart, Rachel McComb, Johan Baeck, Ellen Hooper, Elizabeth Trehu, Haley Laken, Monica Gostissa, Christopher Harvey

1. A.C. Hopkins, M. Yarchoan, J.N. Durham, E.C. Yusko, J.A. Rytlewski, H.S. Robins, D.A. Laheru,

D.T. Le, E.R. Lutz, and E.M. Jaffee, T cell receptor repertoire features associated with survival in

immunotherapy-treated pancreatic ductal adenocarcinoma. JCI Insight, 2018. 3(13): e122092

2. B. C. Carthon, J. D. Wolchok, J. Yuan, A. Kamat, D. S. Ng Tang, J. Sun, G. Ku, P. Troncoso, C. J.

Logothetis, J. P. Allison, and P. Sharma, Preoperative CTLA-4 blockade: tolerability and immune

monitoring in the setting of a presurgical clinical trial. Clin Cancer Res, 2010. 16(10): p. 2861-71.

3. H. Chen, C. I. Liakou, A. Kamat, C. Pettaway, J. F. Ward, D. N. Tang, J. Sun, A. A. Jungbluth, P.

Troncoso, C. Logothetis, and P. Sharma, Anti-CTLA-4 therapy results in higher CD4+ICOShi T cell

frequency and IFN-gamma levels in both nonmalignant and malignant prostate tissues. Proc Natl

Acad Sci U S A, 2009. 106(8): p. 2729-34.

4. D. Ng Tang, Y. Shen, J. Sun, S. Wen, J. D. Wolchok, J. Yuan, J. P. Allison, and P. Sharma,

Increased frequency of ICOS+ CD4 T cells as a pharmacodynamic biomarker for anti-CTLA-4

therapy. Cancer Immunol Res, 2013. 1(4): p. 229-34.

5. S. C. Wei, J. H. Levine, A. P. Cogdill, Y. Zhao, N. A. S. Anang, M. C. Andrews, P. Sharma, J. Wang,

J. A. Wargo, D. Pe'er, and J. P. Allison, Distinct Cellular Mechanisms Underlie Anti-CTLA-4 and

Anti-PD-1 Checkpoint Blockade. Cell, 2017. 170(6): p. 1120-1133 e17.

6. S.C. Wei, N.A.S. Anang, R. Sharma, M.C. Andrews, A. Reuben, J.H. Levine, A.P. Cogdill, J.J.

Mancuso, J.A. Wargo, P. Pe’er, J.P. Allison, Combination anti-CTLA-4 Plus anti-PD-1 Checkpoint

Blockade Utilizes Cellular Mechanisms Partially Distinct From Monotherapies. Proc Natl Acad Sci,

2019. 116(45): p.22699-22709.

Figure 6: EMERGE study staggers sequence of therapies to maximize ICOS induction

and biological activity

Figure 7: Vopratelimab at the medium and low doses will be administered in sequence with ipilimumab. Up to 4 doses of ipilimumab are allowed on

study, as tolerated. Ipilumumab is administered on C1D1 to induce the ICOS hi CD4 T cells and then vopratelimab to bind to and expand ICOS hi

tumor specific T cell population(s). Vopratelimab doses and interval are intended to achieve pulsatile dosing.

A) C)B)

Figure 1: A subset of evaluable subjects in ICONIC with available samples were profiled for the emergence of an ICOS hi CD4 T cell population by flow

cytometry. A waterfall plot showing best target lesion response annotated according to ICOS hi emergence is shown (A). Four subjects with confirmed partial

responses by investigator assessment are indicated in the checkmarks on the waterfall and were profiled longitudinally for both target lesion reduction (B) and

ICOS hi CD4 T cell frequency by flow cytometry (C).

Figure 1: Sustained emergence of ICOS hi CD4 T cells correlates with durable clinical benefit

in ICONIC responders

Figure 2: Vopratelimab activates ICOS hi CD4 T cells that are induced by TCR stimulation

ICOS hi CD4 T cells proliferate in

response to soluble vopratelimab Unprimed ICOS lo CD4 T cells show no

response to soluble vopratelimab

Uns

timul

ated

+ co

ntro

l ant

ibod

y

- con

trol

ant

ibod

y

133.

466

.733

.416

.7 8.3

4.2

2.1

1.0

0.5

0.3

0

20

40

60

80

% P

rolife

rati

on

vopratelimab concentration (nM)

No CD3 stimulation and ICOS lo

Uns

timul

ated

+ co

ntro

l ant

ibod

y

- con

trol

ant

ibod

y

133.

466

.733

.416

.7 8.3

4.2

2.1

1.0

0.5

0.3

0

20

40

60

80

% P

rolife

rati

on

vopratelimab concentration (nM)

CD3 stim induced ICOS hi

Figure 2: Isolated CD4 T cells from healthy donors were stimulated with OKT3 antibody to polyclonally activate all TCRs. ICOS expression was

assessed by flow cytometry in samples with or without OKT3 stimulation (middle flow plot). OKT3 was added in combination with a titration of

vopratelimab and incubated with CFSE labeled CD4 T cells and incubated at 37C for 3 days. A parallel condition using vopratelimab alone was also

tested. Proliferation was assessed by flow cytometry (Left panel and top right). Supernatant from the proliferation experiment was assessed for IFNg

by cytokine bead array (bottom right).

Figure 3: ICOS hi CD4 T cells are comprised of Th1, Tcm, and Tfh subsets and appear in

ICONIC responders across different tumor types and are enriched relative to IO-naïve subjects

A)

B)

E)

C) D)

F) G)

Figure 3: Immune profiling of CD4 T cells from 3 ICONIC responding subjects with ICOS hi emergence (subjects shown in red, blue, and green in Figure 1,

C18D1-C24D1). Figure 2A shows NanoString analysis comparing purified CD4 T cells from these subjects vs CD4 T cells from reference cancer subjects without

this population. Genes shown were significantly different between the groups (FDR-adjusted p-value