Immuno-Oncology. Glioblastoma and CNS tumors 5 July 2016 Siena, Italy

ESMO Preceptorship Programme Immuno-Oncology From the essentials of tumour immunology to clinical application Glioblastoma and CNS tumors 5 July 2016 Siena, Italy Michael Weller Department of Neurology & Brain Tumor Center University Hospital Zurich Frauenklinikstrasse 26 CH-8091 Zurich michael.weller@usz.ch

Immunosuppression in glioblastoma: challenging a popular assumption The brain is an immunoprivileged site: is there need for additional immunosuppression? Glioblastoma cells (may) lack tumor-specific antigens: why additional suppression of a blinded immune system? Is there evidence that immune surveillance accounts for the low incidence of systemic metastasis in glioblastoma? The increased incidence of glioblastoma in the elderly may relate to immune senescence, but why is there no increased risk with immunodeficiency states including AIDS?

Current approaches of immunotherapy for glioblastoma Ipilimumab (anti-ctla-4) (Yervoy, BMS) Pembrolizumab (anti-pd-1) (Keytruda, MSD) Nivolumab (anti-pd-1) (Opdivo, BMS) Atezolizumab (anti-pd-l1) (Roche) TGF-β antisense oligonucleotide (Trabedersen, Antisense Pharma/Isarna) TGF-β receptor antagonists (LY2157299, Galunisertib, Lilly) Vaccination against EGFRvIII (Rindopepimut, Rintega, Celldex) DC/peptide-based immunotherapy (ICT-107, Immunocellular) DC/lysate-based immunotherapy (DCVax, NW Biotherapeutics) Personalized multipeptide vaccination (IMA950, Immatics GAPVAC) DC/CMV-targeted immunotherapy (Duke) IDH-targeted immunotherapy (Heidelberg, and others) Chimeric antigen receptor (CAR) therapy (e.g., EGFRvIII)

Expression and prognostic role of PD-L1 in glioblastoma

Current status of the PD-1/PD-L-1 axis in glioblastoma PD-L1 is expressed in human glioblastoma in vivo TCGA and other public data bases do not define a major prognostic role for PD-L1 expression in glioblastoma The significance as a biomarker of tumoral versus nontumoral PD-L1 expression remains to be determined in glioblastoma, like in many other cancers Preclinical studies demonstrate activity of PD-1 inhibition in rodent glioma models

Immunosuppression in the glioblastoma microenvironment Nduom et al. Neuro-Oncology 2015:17:vii9-vii14

Current approaches of immunotherapy for glioblastoma CheckMate 143

CheckMate 143 Transition from phase II to III

Trial name / ClinicalTrials.gov Identifier Target population Treatment arms Phase Primary endpoint Status (as per March 2016) CheckMate 143 NCT0201771 First recurrence of glioblastoma Experimental: nivolumab Comparator: bevacizumab III OS Accrual completed CheckMate 498 NCT02617589 Newly diagnosed glioblastoma Unmethylated MGMT promoter Experimental: RT + nivolumab Comparator: TMZ/RT TMZ III OS Not yet recruiting CheckMate 548 NCT02667587 Newly diagnosed glioblastoma Methylated MGMT promoter Experimental: TMZ/RT TMZ + nivolumab Comparator: TMZ/RT TMZ + placebo II OS Not yet recruiting NCT02550249 Newly diagnosed or recurrent glioblastoma requiring surgery Nivolumab (neoadjuvant, before surgery) II PD-L1 expression (lymphocytes, tumor) Recruiting NCT02311920 Newly diagnosed glioblastoma Arm 1: TMZ + ipilimumab Arm 2: TMZ + nivolumab Arm 3: TMZ + ipilimumab + nivolumab I MTD (ipilimumab, nivolumab, combination) Recruiting NCT02313272 Recurrent high grade glioma Hypofractionated stereotactic re- RT + bevacizumab + pembrolizumab I MTD (pembrolizumab) Recruiting NCT02337491 Recurrent glioblastoma Cohort A: pembrolizumab + bevacizumab Cohort B: pembrolizumab II Cohort A: PFS-6 Cohort B: MTD (pembrolizumab) Not recruiting NCT02337686 Recurrent glioblastoma Pembrolizumab II PFS-6 Recruiting NCT02658279 Recurrent glioblastoma, Pembrolizumab n/a Response rate Recruiting hypermutator phenotype NCT02336165 Newly diagnosed or recurrent glioblastoma MEDI4736, Bevacizumab + MEDI4736, RT + MEDI4736 II OS-12, PFS-6, OS-6 (depending on treatment) Recruiting

TGF-β and immunosuppression in glioblastoma: clinical studies

Coexpression of wild-type EGFR and EGFRvIII expression in glioblastoma EGFRwt (3C6) GB 1097 EGFRvIII (L8A4) Overlap GB 1097 GB 1122

Are EGFRvIII-positive cells special? Inda et al. Genes Dev 2010;24:1731-45

Cooperation of wild-type EGFR and EGFRvIII in experimental glioblastoma Fan et al. Cancer Cell 2013;24:438-49

Rindopepimut (CDX-110) Vaccine designed to generate a specific immune response against EGFRvIII-expressing tumors Off the shelf vaccine recognized across HLA types Consists of the EGFRvIII antigen (unique 13 amino acid peptide sequence) chemically conjugated to Keyhole Limpet Hemocyanin Delivered as intradermal injection of 500ug rindopepimut with 150ug GM-CSF as an adjuvant Stable, lyophilized formulation LEEKKGNYVVTDHC O S N O O N KLH >30

Progression-free survival (from diagnosis) Survival Probability p = 0.44 Median (months) Comparison to Historical Control ACT III (n=65) 12.3 p = 0.0063 ACT II (n=22) 15.3 p = 0.0029 ACTIVATE (n=18) 14.2 p = 0.0112 Matched historical control (n=17) 6.4 PFS from diagnosis (months) ACT III Primary Endpoint Progression-free survival (PFS) at 5.5 months from vaccination ( 8.5 months from diagnosis): PFS = 66% p = 0.0168 vs. null hypothesis (H 0 ) 53% Vaccinations begin approximately 3 months after diagnosis

Overall survival (from diagnosis) Median (months) OS at 24 Months OS at 36 Months Comparison to Historical Control Survival Probability p = 0.46 ACT III (n=65) 24.6 52% 31% p = <0.0001 ACT II (n=22) 24.4 50% 23% p = 0.0034 ACTIVATE (n=18) 24.6 50% 33% p = 0.0003 Matched historical control (n=17) 15.2 6% 6% OS from diagnosis (months) Vaccinations begin approximately 3 months after diagnosis Median duration of follow-up: ACT III: 48.7 months ACT II: 71.8 months ACTIVATE: 99.3 months

Does Rindopepimut mediate EGFRvIII elimination at recurrence? Pre-Vaccine Primary Tumor Post Vaccine Recurrent Tumor EGFRvIII was selectively eliminated in recurrent tumors for 26/32 (81%) patients across all three studies 15/15 control patients treated with RT/TMZ (+/- CPT-11, bevacizumab or erlotinib) were EGFRvIII(+) at recurrence Robust anti-egfrviii titers in most patients; titers maintained for > 6 months following cessation of treatment 1. Mehta, et. al. JCO 2011

ACT IV Study Design R A N D O M I Z A T I O N Vaccine Priming D1 D15 C1D1 C1D22 Adjuvant Temozolomide and Vaccine Therapy (TMZ-V, 6-12 cycles) Vaccine Maintenance Therapy (VMT) C2D22 C3D22 etc. C1D1 C2D1 etc Follow Up Dose vaccine days 1 and 15 of Vaccine Priming cycle Start cycle within 4 days after randomization and within 7-14 days after completion of CRT Vaccine or control (KLH) is administered Day 22 of each TMZ cycle Begin TMZ no sooner than 6 days after administration of the second vaccine priming dose Begin TMZ no sooner than 28 days after completion of CRT Begin TMZ when ANC 1000/ L and platelets 100,000/ L TMZ dosed days 1-5 of each 28 day cycle If no disease progression after TMZ, continue dosing vaccine every 28 days (Day 1 ±3 days of each 28 day cycle) until intolerance or disease progression Follow-up for overall survival every 12 weeks after disease progression Temozolomide Dosing Vaccine or Control (KLH) Dosing CRT Chemoradiation Therapy Treatment will be discontinued upon disease progression, unacceptable treatment-related toxicity, or patient refusal to continue study treatment

ReACT Bevacizumab naïve Study vaccine + Randomization (1:1) (n=70) bevacizumab No prior bevacizumab or VEGF/ Double-blind VEGF receptor-targeted agents treatment Control + bevacizumab Bevacizumab refractory (Initial cohort: n=25 Expansion cohort: n=up to 73) Progression during or within two months of bevacizumab Open-label treatment Study vaccine + bevacizumab 27 27

Overall Survival Median, months (95% CI) OS 12 OS 18 OS 24 Rindopepimut + BV 11.3 (9.9, 16.2) 44% 32% 25% Control + BV 9.3 (7.1, 11.4) 32% 13% 0% HR = 0.53 (0.32, 0.88) p = 0.0137* Per-protocol population analyses: HR = 0.53 (0.31, 0.90) p = 0.0177* Five patients in the rindopepimut + BV arm, and 1 patient in the control + BV arm, continue survival follow-up without progression per expert review. * Log-rank test (2-sided) 28

Where do we go from here? Rindopepimut Bevacizumab

ICT-107: an autologous six-antigen DC vaccine Matured, Activated, Peptide-loaded DC MHC Class I Six 9-10 amino acid antigen epitopes MAGE-1 (HLA - A1) AIM-2 (A1) gp100 (HLA - A2) IL-13Rα2 (A2) HER2/neu (A2) TRP-2 (A2) Rationale for antigen choice Targeting multiple antigens minimizes tumor escape High expression levels for all antigens on GBM samples Bias toward TAA associated with cancer stem cells Control used in Ph II Matured, activated DC without peptide loading

ICT-107 Phase II Trial Design Surgery Consent Screen and Enroll SOC Chemoradiation Randomize Eligibility Confirmation Vaccine Induction Phase Patient Specific Vaccination ICT 107 or Control 1/wk for 4 wks Maintenance Phase Week 1 SOC Maintenance TMZ Week 2 Rest Week Week 3 Clinical Assessments + maintenance vaccine (ICT 107 or Control) + tumor assessments Week 4 Rest Week Maintenance includes vaccination on a 1, 3, 6, 6 monthly schedule as long as the patient does not recur

Patient demographics Population Characteristic ICT-107 (N=81) Control (N=43) Total (N=124) P-Value Fishers Exact Gender [n(%)] 0.082 Male 44 (54.3%) 31 (72.1%) 75 (60.5%) Female 37 (45.7%) 12 (27.9%) 49 (39.5%) Age Category [n(%)] 0.830 <50 years 20 (24.7%) 12 (27.9%) 32 (25.8%) >50 years 61 (75.3%) 31 (72.1%) 92 (74.2%) MGMT status [n (%)] 0.476 Methylated 28 (34.6%) 18 (41.9%) 46 (37.1%) Unmethylated 47 (58.0%) 24 (55.8%) 71 (57.3%) KPS Category [n (%)] 0.241 100 24 (29.6%) 8 (18.6%) 32 (25.8%) 90 36 (44.4%) 18 (41.9%) 54 (43.5%) <90 20 (24.7%) 17 (39.5%) 37 (29.8%) HLA Type [n (%)] 0.289 A1=Positive, A2=Negative 33 (40.7%) 14 (32.6%) 47 (37.9%) A1=Negative, A2=Positive 42 (51.9%) 22 (51.2%) 64 (51.6%) A1=Positive, A2=Positive 6 (7.4%) 7 (16.3%) 13 (10.5%) Resection Status 0.834 Complete resection 58 (71.6%) 32 (74.4%) 90 (72.6%) Subtotal resection 23 (28.4%) 11 (25.6%) 34 (27.4%)

Progression-free survival ITT population 100% 90% ICT 107 Control 80% ITT Population (N=124) PERCENT SURVIVING 70% 60% 50% 40% 30% 20% Statistically significant treatment benefit ICT 107 N = 81 (63 events) Median = 11.4 months Age stratified HR = 0.640 (0.423 0.968) Age stratified P = 0.033 Control N = 43 (41 events) Median = 10.1 months 10% 0% 0 100 200 300 400 500 600 700 800 900 1000 DAYS

Overall survival ITT population 100% 90% ICT 107 PERCENT SURVIVING 80% 70% 60% 50% 40% 30% ITT Population (N=124) ICT 107 N = 81 (56 events) Median = 18.3 months Age stratified HR = 0.854 (0.547 1.334) Age stratified P = 0.487 Insignificant difference Control 20% 10% Control N = 43 (32 events) Median = 16.7 months 0% 0 200 400 600 800 1000 1200 DAYS

A phase III randomized double-blind, controlled study of ICT-107 with maintenance temozolomide (TMZ) in newly diagnosed glioblastoma following resection and concomitant TMZ chemoradiotherapy (STING - EORTC 1507 Alliance - ICT) Consent HLA-A2 typing Apheresis Stratifications MGMT Age No vs residual < 1 cm 3 tumor Randomize Surgery Screen MRI MGMT and enroll TMZ/RT Eligibility Confirmation MRI Vaccine Induction Phase Patient-Specific Vaccination ICT-107 or Control 1/wk for 4 wks Maintenance Phase DC therapy Maintenance Phase: Maintenance with monthly ICT-107 (patient-specific DC therapy) for 11 months, and once every 6 months thereafter Week until 2depletion or confirmation of progressive disease. CT-107 and TMZ will be administered Rest Weektwo weeks apart during cycle 1 to cycle 6 maintenance TMZ. TMZ will be given Days 1-5 ± 2 days on a 28-day cycle. Study DC therapy will be given on Day 21 ± 2 days. 38

Chimaeric antigen receptor (CAR) therapy: the molecular concept CD28 4-1BB CD3ζ Heczey, Discov Med 16:287-294, 2013

Does immunotherapy for glioblastoma have a future? Most promising field of cancer therapy globally Immunotherapy requires sophisticated logistics Immunotherapy is expensive Immunotherapy may only work in young patients with minimal residual tumor (?)

Quadrennial Meeting of the World Federation of Neuro-Oncology WFNO 2017 in conjunction with the Meeting of the European Association of Neuro-Oncology (EANO) WFNO 2017 & EANO ZURICH, SWITZERLAND Kongresshaus Zürich May 3-7, 2017 INVITATION www.eano.eu