CC-122 Expands Activated and Memory CD4 and CD8 T Cells In Vivo and Induces T Cell Activation Ex Vivo in Subjects with Relapsed or Refractory Diffuse Large B Cell Lymphoma and Multiple Myeloma
Authors: Gandhi Anita K. , Vincent Ribrag , Carpio Cecilia , Stoppa Anne-Marie , Gharibo Mecide Meric , Damian Sylvia , Rasco Drew W , Ysebaert Loïc , Cordoba Raúl , Santoro Armando , Edenfield William J , Pinto Antonio , López-Martín José Antonio , Sancho Juan Manuel , Panizo Carlos , Wei Xin , Hagner Patrick , Waldman Michelle , Hege Kristen , Chopra Rajesh , Pourdehnad Michael 
Published: October 2019

Abstract
Background: CC-122 is a first in class PPMTM pleiotropic pathway modifier compound with multiple biological activities including potent anti-proliferative activity against B lineage cells, anti-angiogenic activity and immunomodulatory effects. CC-122 binds cereblon, and promotes ubiquitination of lymphoid transcription factors Ikaros and Aiolos, leading to their subsequent degradation resulting in activation of T cells. The immunological properties of CC-122 including effects on T cell subset number in vivo and T cell cytokine production ex vivo was explored in subjects with advanced aggressive non-Hodgkin Lymphoma (NHL) and Multiple Myeloma (MM) enrolled in a Phase 1b trial (NCT01421524) at 3 mg QD and 4 and 5 mg 5/7 days dosed in 28 day cycles until disease progression.
Methods: As of June 25, 2015, 76 total DLBCL and MM subjects were enrolled in the expansion phase of the study. Assessments for T cell subset numbers were performed at screening (baseline), cycle 1 day 15 (C1D15), cycle 1 day 22, cycle 2 day 15 and cycle 2 day 22 by flow cytometric immunophenotyping of fresh whole blood. Ex vivo whole blood T cell activation as measured by IL-2, IL-6, IFNg and GM-CSF cytokine production was performed using the anti-CD3 TruCulture Assay. Changes from baseline were evaluated using the t test with p<0.05 considered significant.
Results: T cell subsets which were significantly changed are shown in italics in Table 1. In MM subjects (n=19-21) and DLBCL subjects (n=30-31), CC-122 treatment significantly expanded several T cell activator and memory T cell subsets while decreasing naïve T cells. A single dose of CC-122 on C1D1 activated T cells as measured in an ex vivo T cell activation assay in MM subjects (n=6-13) and DLBCL subjects (n=5-12) (Table 2). In addition, we evaluated potential correlations of clinical outcome with baseline biomarker and biomarker changes upon CC-122 treatment.
Table 1. MM n=19-21 NHL n=30-31 T cell Parameter Phenotype Baseline cells/mm3 Median % Change at C1D15 from Baseline P Baseline cells/mm3 Median % Change at C1D15 from Baseline P Total T cells ABS CD3+ 636.9 17.733 0.24747 522.94 43.83 0.03638 Total T helper ABS CD3+/CD4+/CD8- 275.38 18.333 0.07812 238.96 13.428 0.09893 T helper Activated ABS CD3+/CD4+/CD8-/HLA-DR+ 62.34 105.769 0.00238 57.11 78.571 0.01567 T helper Total Naïve ABS CD3+/CD4+/CD8-/45RA+/45RO- 69.07 -54.545 0.0038 47.94 -47.841 0.03159 T helper Effector CD62L+ ABS CD3+/CD4+/CD8-/45RA+/62L+ 117.62 0 0.16621 93.74 -6 0.14611 T helper Effector CD62L- ABS CD3+/CD4+/CD8-/45RA+/62L- 21.38 -25.862 0.15196 28.44 -20.161 0.08548 T helper Total Memory ABS CD3+/CD4+/CD8-/45RA-/45RO+ 137.93 41.176 0.05373 119.15 36 0.01915 T helper Central Memory ABS CD3+/CD4+/CD8-/45RA-/62L+ 91.9 47.451 0.01953 75.74 37.143 0.01275 T helper Effector Memory ABS CD3+/CD4+/CD8-/45RA-/62L- 44.17 18.147 0.17768 41.07 19.375 0.04749 Total T cytotoxic ABS CD3+/CD4-/CD8+ 334.07 18.044 0.27499 265.7 43.823 0.0127 T cytotoxic Activated ABS CD3+/CD4-/CD8+ /HLA-DR+ 176.76 100 0.20781 121.3 96.454 0.00686 T cytotoxic Total Naïve ABS CD3+/CD4-/CD8+ /45RA+/45RO- 173.69 -35.714 0.15126 116.04 -32.667 0.89774 T cytotoxic Effector CD62L+ ABS CD3+/CD4-/CD8+ /45RA+/62L+ 127.28 20.727 0.24151 93.43 17.419 0.09599 T cytotoxic Effector CD62L- ABS CD3+/CD4-/CD8+ /45RA+/62L- 151.72 -14.286 0.28394 120.98 -18.301 0.18068 T cytotoxic Total Memory ABS CD3+/CD4-/CD8+ /45RA-/45RO+ 55.03 167.402 0.26292 54.13 184.615 0.01034 T cytotoxic Central Memory ABS CD3+/CD4-/CD8+ /45RA-/62L+ 26.83 160.417 0.00013 18.78 264.087 0.00169 T cytotoxic Effector Memory ABS CD3+/CD4-/CD8+ /45RA-/62L- 28.14 133.333 0.00107 32.59 100 0.01939
Table 2. MM n=6-13 NHL n=5-12 Cytokine Baseline cells/mm3 Median % Change from Baseline P Baseline cells/mm3 Median % Change from Baseline P IL-2 98.71 603.509 0.01329 104.5 437.194 0.01761 IL-6 131.84 124.108 0.03426 99.64 21.68 0.2692 GM-CSF 90.24 636.207 0.06608 212.96 144.601 0.16744 IFNg 271.85 404.98 0.0056 554.64 162.451 0.03024
Conclusions: CC-122 significantly increases the proportion of several cytotoxic and helper T cells subsets while decreasing naïve T cells in both DLBCL and MM subjects. CC-122 also significantly activates T cells ex vivo as measured by cytokine production. These results indicate that CC-122 is a potent modulator of T cell numbers and activation and this may serve as rationale for combinations with other immunotherapies.

Disclosures
Gandhi: Celgene: Employment, Equity Ownership. Off Label Use: CC-122 is a first in class PPM(TM) pleiotropic pathway modifier with multiple biological activities against B lineage cells. Vincent:Pharmamar: Honoraria, Membership on an entity's Board of Directors or advisory committees; Servier: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Gilead: Membership on an entity's Board of Directors or advisory committees; Esai: Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Research Funding. Carpio:Celgene: Research Funding. Stoppa:Amgen: Consultancy, Honoraria; Celgene: Consultancy, Honoraria, Research Funding; Janssen: Consultancy, Honoraria; Novartis: Consultancy, Honoraria. Gharibo:Celgene: Research Funding. Damian:Celgene: Research Funding. Rasco:Celgene: Research Funding; Asana BioSciences, LLC: Research Funding. Ysebaert:Celgene: Research Funding. Cordoba:Celgene: Research Funding. Edenfield:Celgene: Research Funding. Pinto:Celgene Corporation: Honoraria; Takeda: Honoraria, Research Funding; Spectrum: Honoraria. López-Martín:Celgene: Research Funding. Sancho:Celgene: Research Funding. Panizo:Janssen: Speakers Bureau; Takeda: Speakers Bureau; Roche: Speakers Bureau; Celgene: Research Funding. Wei:Celgene: Employment, Equity Ownership. Hagner:Celgene: Employment, Equity Ownership. Waldman:Celgene: Employment, Equity Ownership. Hege:Celgene Corporation: Employment, Equity Ownership. Chopra:Celgene Corporation: Employment, Equity Ownership. Pourdehnad:Celgene: Employment.