Engineering T cells for HCC Immunotherapy

1. Engineering T cells for HCC Immunotherapy • Yukai He • Medical College of Georgia, • Augusta University 9-22-2019, ILCA, Chicago

2. Disclosure My employer, Medical College of Georgia, holds the patents of TCRs and CARs Consultant: CBMG, Cupertino, CA

3. Recruiting a highly motivated postdoc with immunology background

4. Immunotherapy for HCC • Cancer vaccines: Not effective yet. a. Together with ACT • b. Neoantigencancer vaccines • Checkpoint blockade effective in ~20% of patients (El-Khoueiry et al, 2017, Lancet) • - Checkpoint blockade plus anti- angiogenesis, 30-40% response rate • Engineered T cells therapy are emerging

5. Hong et al, 2014 Developing novel GPC3 mAbs and novel CAR-Ts HCC CAR-T Cancer Vaccines Oncolytic virus in situ vaccines ACT TCR-T Zhu et al, 2018

6. Identify TCRs for HCC immunotherapy

7. TCR

8. Lentivector prime & peptide boost induce a high level of AFP-specific T cells AFP-lv Yibing Peng Peptide Trivax iv Peptides PolyIC Anti-CD40 Ab HLA Tg mice Peptide Boost Lentivector Prime

9. The therapeutic potential of adoptive transfer of AFP-specific T cells Splenocytes from immunized mice HepG2 2cm Splenocytes (2 million AFP Tet+ T cells)

10. TCR This population cells must have the TCR that recognize human HCC tumor cells

11. Identification of TCRs: Via T cell hybridoma technique Wei Zhu Maintain the diversity of T cell repertoire Determine TCR affinity before cloning Identify and clone the paired TCR α and β chains Nine (9) unique TCRs specific for AFP158 epitope, the most frequently presented epitope were identified. TCRs have different affinity.

13. No mispairing with endogenous human TCR

14. Specifically recognize AFP+ HLA-A2 HCC tumor cells

15. Adoptive transfer of human TCR-T generates antitumor effect against HCC xenografts in NSG mice

17. Summary I: • 1.9 TCRs with different affinity • 2. Potent antitumor effects in preclinical models. • 3.Wrapping up the cross-reactivity study • A. On-target/off-tumor • B. Off-target • C. Alloreactivity TCRs have different affinity, antitumor effects and cross-reactivity. Selected 1-2 TCR with no cross-reactivity with normal human cells

18. GPC3-specific CAR-Ts

19. CARTs for HCC • GPC3-specific CARTs • GC33 antibody • YP7, HN3 antibodies • MHC/AFP158-specific CARTs • Intracellular antigen • MHC-restricted

20. HN3 (14 Carbon chain GPC3 structure and antibodies (524-563) YP7 Adopted from Ho M, Kim H. 2011 And Haruyama Y, Kataoka H. 2016

21. Developing novel GPC3-specific CART for HCC immunotherapy • Develop GPC3-specific antibodies A. 20 mAbs B. 14 of them can also bind to GPC3+ tumor cells • Create CAR-T cells Dr. Xiaotao Jiang

22. 1. Develop GPC3-specific antibodies

29. Soluble GPC3 does not activate CARTs, nor inhibit the killing of GPC3+ tumor cells

32. Summary II • 1. Develop 3 hGPC3-specific and HCC-specific mAbs (6G11, 8F8, and 12D7). • 2. Create 3 corresponding CARTs from the 3 mAbs, which expand after HCC cell stimulation. • 3. The 6G11 and 8F8 CARTs targeting hGPC3 N- or C- epitope have strong effector function. • 4. Adoptive transfer of 6G11 and 8F8, but not 12D7 CARTs results in tumor regression.

34. Acknowledgement • Yukai’s lab: • Yibing Peng • Leidy Caraballo Galva • Catherine Cai • Yanxia Shao • Previous members • Qi Li • Dr. Xiaotao Jiang • Dr. Wei Zhu • Dr. Lan Wang • Dr. Yuan Hong • Collaborators: • Dr. Esteban Celis • Dr. Ignatowicz (Georgia State University) • Georgetown University • Dr. Aiwu (Ruth) He • Funding: • NCI R01 CA168912, NCI R01 CA235159 • Georgia Cancer Center intramural grant

35. HCC is an increasing problem in USA • In US, the HCC incidence rate increases the fastest, has doubled in 20 years, mainly due to non-viral factors. • Worldwide, HCC is the 6th most common cancer, 850,000 cases. • Few drugs are available with limited efficacy. HCC is the 2ndleading cause of cancer death among man (>600,000).

36. TCR CAR Nature Made Man Made