New developments in the field of CAR cell therapy

(Vortragsslides 2 Presentations)

CAR-T cells to prevent antigen escape

Marcela V. Maus, MD, Ph.D. Director, Cellular lmmunotherapy Program, MGH

Approaches to multi-targeted CART cells:

• Transduce  2 different cell populations with 2 different vectors

- Savoldo JCI 2011 used this method to demonstrate 28z > z

• Transduce 1 cell population with 2 vectors

- Ruella JCI 2016 used this method to show that 1 cell population > pooled cell populations

• Transduce 1 cell population with 1 "tandem" CAR

- (Zah/Chen CIR 2016 with CD19/20; Qin/Fry Mol Ther One CD19/22)

• Binder that binds 2 related antigens (SchmidtsBloodAdv, 2019)

• CAR T that secretes a BiTE (Choi Nat Biotech 2019)

 

Targeting BCMA and TACI on multiple myeloma

  • APRIL (a proliferation-inducing ligand) is produced by myeloid cells in the BM microenvironment
  • soluble APRIL binds to BCMA and TACI and promotes proliferation and survival of MM
  • Trimeric APRIL-based CART - cells are effective in BCMA+ and BCMA- MM

CARs targeting glioblastoma can induce regression with multiple doses, local administration - but still induce antigen escape relapse

One approach to tumor heterogeneity: target 2 antigens: Tandem CART cells targeting HER2 and IL 13Ra2 mitigate tumor antigen escape

NCT02209376 Phase 1 Study of a single intravenous dose of EGFRvlll CART in patients with recurrent EGFRvlll+ GBM

  • EGFRvlll is an oncogenic mutation Occurring in ~20% of patients with glioblastoma Frequently also with amplification of wt EG FR

CART-EGFRvlll traffic to tumor, target antigen, but there is antigen heterogeneity and Treg infiltration 

Can we design a CAR T cell that targets another antigen and bypasses or co-opts the infiltrating regulatory T cells? 

 

T-cell Engaging Antibody Molecule; TEAM can target the "undruggable:" - Local site - Rapid clearance - Can re-direct Tregs

CAR-TEAMs induce responses in mixed EGFRvlll+ and EGFRvlll- GBM in vivo 

CAR-TEAMs induce responses in EGFRvlll- GBM in vivo

No evidence of TEAM-E (EGFR)-related toxicity in skin graft model 

CAR-TEAM-E Clinical Trial: A PHASE I CLINICAL TRIAL OF INTRAVENTRICULAR CARV3.TEAM-E T CELLS IN PATIENTS WITH GBM (INCIPIENT) - proposed study arms:

Arm 1: Recurrent GBM, EGFRvlll mutant based on tissue within 30 days of consent 

Arm 2: Newly diagnosed GBM, MGMT unmethylated, viii mutant 

Arm 3: Recurrent GBM, EGFRvlll negative based on tissue within 30 days of consent 

CONCLUSIONS

• Combination therapy with one-shot CAR-TEAMs has promise for overcoming tumor heterogeneity • TEAMs secreted by CART can be delivered to tumor compartments and do not have systemic on-target toxicities known to occur with antibodies • Local administration, multiple doses, multi-targeted approaches are likely to be more effective and durable • IND and protocol expected to open at MGH in H1 2021

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Anti-CD123 CAR t cells for blastic plasmacytoid dendritic cell neoplasm (BPDCN)

Francine Garnache Ottou

 

no summary & no slides available

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Gene Editing with CRISPR-Cas9 to Engineer CAR T Cells

Edward A. Stadtmauer, MD 

Adoptive T cell therapy (three major approaches) 

(June et al Sci Trans Med 2015)

Successes of CART19 Therapy (JULIET; ZUMA-1)

BCMA CART cells - initial studies, refractory pts

BCMA CAR T cells - lessons from initial studies (Probably not curative in refractory patients)

Ways to Improve CAR T 

• Antigern Escape • Alternate Targets (CD38, SLAMF7 (CS1), GPRC5D, NY-ES0-1) • Dual Targeting Strategies (BCMA + CD19) • Enhancing Antigen expression

• Maximize T cell function • Optimize T cell subsets • Harvest earlier in disease course • Check-point inhibition

• Improve CAR construct • Signaling domains • Antigen binding site • Hinge area

• Decrease 'vein-vein' time • Gene editing for 'off-the-shelf allogeneic CAR T • More rapid manufacturing

Medicines Through Gene Editing - Genome editing is a set of methods used to change the DNA of cells with single base-pair precision.

Medical applications include: • Correction of variants that cause monogenic diseases (SSD) • Cell-based regenerative medicine • Enhancement of CAR T cell Therapy

Foundational principle: 1994 Discovery that creation of a break in DNA double-strand in a target gene could stimulate DNA repair when a 'donor' template strand of DNA (guide DNA) was provided at the same time the break was created.

• Endonucleases: enzymes that cleave the bonds within a polynucleotide chain (DNA or RNA 'breakers')

• Engineered endonucleases that recognize target sites and stimulate genome editing in endogenous genes.

• Zinc-finger nucleases

• DNA binding protein with a specific recognition sequence fused to a nonspecific nuclease domain.

• Homing endonucleases • Transcription activator-like effector nuclease (TALEN)

• Creates a site-specific double-stranded break in the genome that activates repair

CRISPR-Cas9 Gene Editing (Clustered Regularly interspaced Short Palindromic Repeats) endonuclease

• Developed from a bacterial adaptive immune system • Cas9 nuclease cleaves DNA after an induced conformational change and then binding of gRNA to the DNA target site • Unlike other gene editing system1s, Cas9-gRNA guidance to target by Watson-Crick base-pairing.

By combining the tools of synthetic biology such as TCRs and CAR T and CRISPR-Cas9, we have an unprecedented opportunity to optimally program T cells and improve adoptive immunotherapy

• Is it feasible to generate multipllexed CRISPR­edited T cells at the scale needed for a clinical infusion product? • Can patients receive such a T cell product safely following lymphodepletion? • Will these cells expand, persist and elicit anti-tumor activity in patients?

First-in-Human Assessment of Feasibility and Safety of Multiplex.ed Genetic Engineering of Autologous T Cells Expressing NY-ESO -1 TCR and CRISPR/Cas9 Gene Edited to Elim1inate Endogenous TCR and PD-1 (NYCE T cells) in Advanced Multiple Myeloma (MM) and Sarcoma

Generation of a Novel NY-ES0-1 Transgenic T cell Receptor (TCR)

• Expression of NY-ES0-1 and LAGE-1, cancer testis antigens, is limited to a variety of cancers and germ cells of the testis • NY-ES0-1 and LAGE-1 genes encode very homologous proteins (common SLLMWTTQC epitope) • Prior human studies of NY-ES0-1 TCR-expressing T cells show safety and evidence of anti-tumor activity in melanoma, sarcoma and myeloma • Lack of long-term durable responses underscores the need to improve the clinical efficacy of this approach.

Study Schema: NY-ES0-1-redirected CRISPR Edited T Cells (NYCE T Cells): ClinicalTrials.gov Identifier: NCT03399448

Conclusions

• Generation of multiplexed genetic engineering of autologous T cells expressing NY-ES0-1 TCR and CRISPR/Cas9 gene edited to eliminate endogenous TCR and PD-1 (NYCE T cells) is feasible • Three patients with advanced cancer have safely received NYCE T cells after lymphodepletion • Engineered T cells expand, survive and persist long-term in patients • Best overall response achieved after NYCE T cell infusion to date is stable disease.

Allogeneic approaches are associated with two major issues: GvHD and rejection 

ALPHA Study (NCT03939026) Design and Endpoints Phase 1, Open-label, Multicenter Dose Escalation Study

Phase 1 Trial of PBCAR0191, a CD19 Targeted Allogeneic CART see paper

Available allogeneic: CAR·expressed immune effector cells in MM: Future of CAR T cells in multiple myeloma