Predictive Biomarkers for PD1 Pathway Inhibitor Immunotherapy

Transcription

1 Predictive Biomarkers for PD1 Pathway Inhibitor Immunotherapy Michael B. Atkins, M.D. Deputy Director Georgetown-Lombardi Comprehensive Cancer Center

2 Michael Atkins, MD Consulting Fees (e.g., advisory boards): Genentech, BMS, Merck, Costim/CCAM I intend to reference unlabeled/unapproved uses of drugs or products in my presentation. Please list name of device/drug and unlabeled/unapproved use: Ant. PD1 / Ant. PDL1

3 Outline Tumor microenvironment PDL1 expression Immune infiltration Other potential factors Current clinical application

4 High expression of vascular markers, macrophages, fibroblasts + Low inflammation and chemokines, few lymphocytes = Poor effector cell trafficking Gajewski, Curr Opin Immun 2011

5 High levels of innate immune signals, chemokines for T cell recruitment, activated tumor specific T cells, but negative immune regulators dominate Gajewski, Curr Opin Immun 2011

6 Proportion of patients Preliminary molecular marker studies: Correlation of PD-L1 expression in pretreatment tumor biopsies with clinical outcomes 13/31 18/31 0/18 18/18 p=0.002 * Melanoma Kidney Lung 49 patients include 20 with melanoma,13 NSCLC, 7 colon, 6 kidney, and 3 prostate cancer. * Normal renal glomerulus

7 Issues with PDL1 as a Biomarker (1) PD-L1 neg can t be relied on Assays are technically difficult, imperfect; results may be different depending on the antibody/assay 5% expression, tumor heterogeneity, and inducible gene = sampling error (false negs) Primary not equivalent to metastasis PD-L2 could contribute in some tumors May be less relevant in combination trials

8 Plenty Responses in PD-L1 neg Pts

9 Anti-PDL1 can stain tumor or infiltrating inflammatory cells: What do you measure? Signoretti, Freeman, McDermott DFHCC KCA SPORE

10 [TITLE] Presented By John D. Powderly, MD at 2013 ASCO Annual Meeting

11 [TITLE] -Only 35% (36/103) of patients PDL of 29 responders not PDL1+ Presented By John D. Powderly, MD at 2013 ASCO Annual Meeting

12 PDL1 expression-what cut-off do you use? Do you include immune infiltrate? More stringent cutoff-fewer patients, higher RR, but exclude more responders

13 Waterfall Plots

14 Relationship between Primary and Met in RCC Concordance of only 70%; (Figure) Primary heterogenous; Met staining more homogeneous PDL1 expression associated with highest Fuhrman grade Signoretti, Freeman, McDermott DFHCC KCA SPORE-GU ASCO

15 Can PDL2 expression account for responses in PDL1 neg tumor and less activity with PDL1 ab? Signoretti, Freeman, McDermott DFHCC KCA SPORE

16 Ipi/Nivo- Tumor Response Cohort 2: 1 mg/kg nivolumab + 3 mg/kg ipilimumab All patients in concurrent cohorts First occurrence of new lesion Wolchok et al. ASCO #9012 ORR >80% Tumor Reduction ipilimumab 7% <3% nivolumab 28% <2% combination (cohort 2) 53% 41%

17 PD-L1 Expression and Response Agent(s) Tumor Type n RR (%) PD-L1 pos Nivolumab 1 Multiple Solid Tumors RR(%) PD-L1 neg 42 36% 0% MPDL3280A 2 Kidney Cancer 47 20% 10% Nivolumab 3 Melanoma 34 44% 17% Nivo/Ipi 4 Melanoma 27 40% 47% 1 Topalian et al, NEJM, 2012, 2 Cho et al ASCO 2013, 3 Grosso et al ASCO 2013, 4 Wolchok et al, NEJM 2013

18 No. patients Correlation of tumor PD-L1 expression with tumor type in 49 patients treated with anti-pd-1 0 No. OR/total: 8/20 3/13 2/6 0/7 0/3 Patients were considered PD-L1(+) if any tumor biopsy had 5% of tumor cells expressing cell surface PD-L1, using mab 5H1 and manual staining technique.

19 Issues with PDL1 as a Biomarker (2) Why don t all PDL1+ tumors respond? Expression could be constitutive due to oncogene (? No immune infiltrate) Expression of other checkpoint inhibitors

20 2 Mechanisms for PD-L1 up-regulation in tumors Innate Resistance TUMOR Oncogenic Pathway MHC-pep TCR PD-1 PD-L1 T Cell Constitutive tumor signaling induces PD-L1 on tumor cells Adaptive Resistance T cell-induced PD-L1 up-regulation TUMOR T Cell TUMOR T Cell Stats IFN-g

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22 Is a measure of immune infiltration a better predictor of responsiveness?

23 Focal tumor cell surface PD-L1 expression in melanoma: geographic co-localization with infiltrating immune cells Tumor Lymphs Taube et al. Science Translational Med 2012

24 Immune infiltrates at the boundary of PD-L1+ melanoma cells express IFN-g PD-L1 H&E H&E qrt-pcr demonstrates IFN-g in PD-L1(+) but not PD-L1(-) melanomas (Taube et al., STM 2012) Gene expression profiling (DASL) reveals inflammatory signature

25 % of cases Correlation of PD-L1 expression with the presence of TILs in 150 melanocytic lesions Are these the PDL1 neg responders? Is this true of other tumor types? P< TILs are necessary but not sufficient for PD-L1 expression in melanoma. Still only 38% express PDL1 (Taube et al., Science Transl Med 2012)

26 Issues with immune infiltrate as Biomarker (1) What biomarker to use? CD8/Treg ratio Granzyme, perforin, TH1 cytokines Chemokines (expression signature) Pre-treatment biopsy might not represent ontreatment effects PD1 ab responsive tumors may not have typical immune responsive signature (e.g. MK-3475 as active in ipi failures)

27 [TITLE] Presented By John D. Powderly, MD at 2013 ASCO Annual Meeting

28 [TITLE] Presented By John D. Powderly, MD at 2013 ASCO Annual Meeting

29 [TITLE] Presented By John D. Powderly, MD at 2013 ASCO Annual Meeting

30 [TITLE] Presented By John D. Powderly, MD at 2013 ASCO Annual Meeting

31 12-Chemokine Gene Signature: Non-Lymph Node Melanoma Metastases Mule et al Nature Scientific Reports 2012

32 Ectopic Lymph Node Structures in Melanoma Tumor

33 Interrogation of a 12-Chemokine Gene Expression Signature across Solid Tumors of Differing Histology: Principal Component Analysis TCC Samples Primary & Mets 14,492 samples in total PCA score as a measure of chemokine signal Top 10% of samples were selected as high High expression tissues includes skin, lung, oral, cervix Total # CEL files # Above 90 th percentil e % Above 90 th percentile Tissue Type Bladder Brain Breast Cervix Endometrium Esophagus Kidney Large_Bowel Larynx Liver Lung Oral_Cavity Ovary Pancreas Peritoneum Prostate Rectum-Anus Renal_Pelvis Skin Small_Intestine Soft_Tissue Stomach Thyroid Tongue Uterus

34 Issues with immune infiltrate as Biomarker (2) Not all tumors with immune infiltrates express PDL1 or respond to PD1 pathway blockade - (e.g. CRC, breast ca). Why? Other checkpoints involved? Wrong immune cells? Other?

35 Exhausted TIL express Multiple Immunoinhibitory Receptors: These are druggable targets for tumor immunotherapy 37

36 Is there a role for mutational frequency in tumor selection for PD1 pathway blockade?

37 Somatic mutation frequencies observed in exomes from 3,083 tumour normal pairs. MS Lawrence et al. Nature 000, 1-5 (2013) doi: /nature

38 Is there a role for mutational frequency in tumor selection for PD1 pathway blockade? Does this relate to individual patients? Particular mutations?

39 How best to use biomarkers? Identify disease types to treat Those with high level of PDL1 expression and Th1 and/or chemokine signature Those lacking oncogenic driver of PDL1 Those where PDL1 expression associated with no benefit with conventional therapy (e.g. RCC) Those with high mutational frequency (neo-antigens) Obtain fresh biopsy prior to treatment for exploratory and possibly stratification, but not selection purposes

40 How does one turn a non-inflamed, PDL1 negative tumor into a immune responsive tumor? SRS Molecularly targeted therapy Tumor based vaccine? CAR T cells or other modified T cells