IMMU-06. COMBINATORIAL IMMUNE CHECKPOINT INHIBITORS FOR TARGETED INTRATUMORAL DELIVERY IN GBM

2021 ◽  
Vol 23 (Supplement_6) ◽  
pp. vi93-vi93
Author(s):  
Stephanie Sanders ◽  
Denise Herpai ◽  
Waldemar Debinski

Abstract Glioblastoma (GBM) is an immunologically cold tumor. Using single cell sequencing of CD45+ cells we confirmed that T cells are present within GBM samples. These T cells are positive for exhaustion markers such as LAG3 and TIGIT, as well as CTLA4 and PD1 checkpoint receptors. Modulating T cell activity through use of immune checkpoint inhibitors (ICIs) has shown efficacy in the treatment of a variety of solid tumors, and the combination of anti-CTLA4 and anti-PD1 ICIs has shown increased efficacy over use of a single therapeutic. Additionally, targeting ICIs to the tumor cells may increase efficacy of this treatment. We therefore constructed a combinatorial ICI redirected to GBM via interleukin 13 receptor alpha 2 (IL13RA2), a receptor over-expressed on the majority of GBM cells but not normal brain. The first component of the construct, labeled with a histidine tag, targets CTLA4 while the second component, tagged with a StrepII tag, targets PD1. The tags added to the constructs will allow for purification of a combinatorial heterodimer simultaneously targeting PD1, CTLA4 and IL13RA2. We purified individual components via fast protein liquid chromatography (FPLC) using a proteinG column followed by a HisTrap or StrepTrap column. We obtained a recombinant, targeted multivalent ICI at > 95% purity. We found that these constructs are able to bind their target receptors via ELISA in which the Kd values ranged from picomolar to low nanomolar range. Additionally, our constructs bind their target on live cells by flow cytometry. We next designed a heterodimeric construct which can combinatorially target CTLA4 and PD1 while also directing the ICI therapy to GBM. These constructs in conjunction with other immune stimulants like cytotoxic therapies are intended to facilitate the interaction between T cells and GBM tumor cells directly in a tumor microenvironment.

2015 ◽  
Vol 2015 ◽  
pp. 1-12 ◽  
Author(s):  
Ayumu Ito ◽  
Shunsuke Kondo ◽  
Kohei Tada ◽  
Shigehisa Kitano

Recent progress in cancer immunotherapy has been remarkable. Most striking are the clinical development and approval of immunomodulators, also known as immune checkpoint inhibitors. These monoclonal antibodies (mAb) are directed to immune checkpoint molecules, which are expressed on immune cells and mediate signals to attenuate excessive immune reactions. Although mAbs targeting tumor associated antigens, such as anti-CD20 mAb and anti-Her2 mAb, directly recognize tumor cells and induce cell death, immune checkpoint inhibitors restore and augment the antitumor immune activities of cytotoxic T cells by blocking immune checkpoint molecules on T cells or their ligands on antigen presenting and tumor cells. Based on preclinical data, many clinical trials have demonstrated the acceptable safety profiles and efficacies of immune checkpoint inhibitors in a variety of cancers. The first in class approved immune checkpoint inhibitor is ipilimumab, an anti-CTLA-4 (cytotoxic T lymphocyte antigen-4) mAb. Two pivotal phase III randomized controlled trials demonstrated a survival benefit in patients with metastatic melanoma. In 2011, the US Food and Drug Administration (FDA) approved ipilimumab for metastatic melanoma. Several clinical trials have since investigated new agents, alone and in combination, for various cancers. In this review, we discuss the current development status of and future challenges in utilizing immune checkpoint inhibitors.


Immunotherapy ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 587-603
Author(s):  
Mobina Jalalvand ◽  
Farzaneh Darbeheshti ◽  
Nima Rezaei

Cancer initiation and progression are associated with immune system responses. Tumor cells use various tricks to scape of immune system, such as activating immune checkpoint pathways that induce immunosuppressive functions. Among the different immune checkpoint receptors, CTLA-4 and PD-1/PD-L1 are prominent therapeutic targets in different cancers. Although the US FDA has approved some immune checkpoint inhibitors for several cancers, concerning breast cancer still different clinical trials are looking for optimizing efficacy and decreasing immune-related adverse events. This review will discuss the existing body of knowledge with regard to cross-talk between immune system and tumor cells and then explore immune checkpoint-related signaling pathways in the context of breast tumors. Finally, we highlight the application of different immune checkpoint blockers in breast cancer patients.


2017 ◽  
Vol 8 (1) ◽  
Author(s):  
Shawn T. Beug ◽  
Caroline E. Beauregard ◽  
Cristin Healy ◽  
Tarun Sanda ◽  
Martine St-Jean ◽  
...  

Abstract Small-molecule inhibitor of apoptosis (IAP) antagonists, called Smac mimetic compounds (SMCs), sensitize tumours to TNF-α-induced killing while simultaneously blocking TNF-α growth-promoting activities. SMCs also regulate several immunomodulatory properties within immune cells. We report that SMCs synergize with innate immune stimulants and immune checkpoint inhibitor biologics to produce durable cures in mouse models of glioblastoma in which single agent therapy is ineffective. The complementation of activities between these classes of therapeutics is dependent on cytotoxic T-cell activity and is associated with a reduction in immunosuppressive T-cells. Notably, the synergistic effect is dependent on type I IFN and TNF-α signalling. Furthermore, our results implicate an important role for TNF-α-producing cytotoxic T-cells in mediating the anti-cancer effects of immune checkpoint inhibitors when combined with SMCs. Overall, this combinatorial approach could be highly effective in clinical application as it allows for cooperative and complimentary mechanisms in the immune cell-mediated death of cancer cells.


2018 ◽  
Vol 1 (1) ◽  
pp. 28-32
Author(s):  
Piyawat Komolmit

การรักษามะเร็งด้วยแนวความคิดของการกระตุ้นให้ภูมิต้านทานของร่างกายไปทำลายเซลล์มะเร็งนั้น ปัจจุบันได้รับการพิสูจน์ชัดว่าวิธีการนี้สามารถหยุดยั้งการแพร่กระจายของเซลล์มะเร็ง โดยไม่ก่อให้เกิดภาวะแทรกซ้อนทางปฏิกิริยาภูมิต้านทานต่ออวัยวะส่วนอื่นที่รุนแรง สามารถนำมาใช้ทางคลินิกได้ ยุคของการรักษามะเร็งกำลังเปลี่ยนจากยุคของยาเคมีบำบัดเข้าสู่การรักษาด้วยภูมิต้านทาน หรือ immunotherapy ยากลุ่ม Immune checkpoint inhibitors โดยเฉพาะ PD-1 กับ CTLA-4 inhibitors จะเข้ามามีบทบาทในการรักษามะเร็งตับในระยะเวลาอันใกล้ จำเป็นแพทย์จะต้องมีความรู้ความเข้าใจในพื้นฐานของ immune checkpoints และยาที่ไปยับยั้งโมเลกุลเหล่านี้ Figure 1 เมื่อ T cells รับรู้แอนทิเจนผ่านทาง TCR/MHC จะมีปฏิกิริยาระหว่าง co-receptors หรือ immune checkpoints กับ ligands บน APCs หรือ เซลล์มะเร็ง ทั้งแบบกระตุ้น (co-stimulation) หรือยับยั้ง (co-inhibition) TCR = T cell receptor, MHC = major histocompatibility complex


2021 ◽  
Vol 22 (10) ◽  
pp. 5207
Author(s):  
Chi Yan ◽  
Jinming Yang ◽  
Nabil Saleh ◽  
Sheau-Chiann Chen ◽  
Gregory D. Ayers ◽  
...  

Objectives: Inhibition of the PI3K/mTOR pathway suppresses breast cancer (BC) growth, enhances anti-tumor immune responses, and works synergistically with immune checkpoint inhibitors (ICI). The objective here was to identify a subclass of PI3K inhibitors that, when combined with paclitaxel, is effective in enhancing response to ICI. Methods: C57BL/6 mice were orthotopically implanted with syngeneic luminal/triple-negative-like PyMT cells exhibiting high endogenous PI3K activity. Tumor growth in response to treatment with anti-PD-1 + anti-CTLA-4 (ICI), paclitaxel (PTX), and either the PI3Kα-specific inhibitor alpelisib, the pan-PI3K inhibitor copanlisib, or the broad spectrum PI3K/mTOR inhibitor gedatolisib was evaluated in reference to monotherapy or combinations of these therapies. Effects of these therapeutics on intratumoral immune populations were determined by multicolor FACS. Results: Treatment with alpelisib + PTX inhibited PyMT tumor growth and increased tumor-infiltrating granulocytes but did not significantly affect the number of tumor-infiltrating CD8+ T cells and did not synergize with ICI. Copanlisib + PTX + ICI significantly inhibited PyMT growth and increased activation of intratumoral CD8+ T cells as compared to ICI alone, yet did not inhibit tumor growth more than ICI alone. In contrast, gedatolisib + ICI resulted in significantly greater inhibition of tumor growth compared to ICI alone and induced durable dendritic-cell, CD8+ T-cell, and NK-cell responses. Adding PTX to this regimen yielded complete regression in 60% of tumors. Conclusion: PI3K/mTOR inhibition plus PTX heightens response to ICI and may provide a viable therapeutic approach for treatment of metastatic BC.


2021 ◽  
Vol 9 (Suppl 3) ◽  
pp. A570-A570
Author(s):  
Chen Zhao ◽  
Matthew Mule ◽  
Andrew Martins ◽  
Iago Pinal Fernandez ◽  
Renee Donahue ◽  
...  

BackgroundImmune checkpoint inhibitors (ICIs) have changed the cancer treatment landscape, but immune-related adverse events (irAEs) can affect a wide range of tissues in patients receiving ICIs. Severe irAEs can be life-threatening or fatal and prohibit patients from receiving further ICI treatment. While the clinical features of irAEs are well documented, the pathological mechanisms and predictive biomarkers are largely unknown. In addition, there is a critical need to preserve ICI-induced anti-tumor immunity while controlling for irAEs, which requires deciphering molecular and cellular signatures associated specifically with irAEs beyond those more generally linked to anti-tumor immunity.MethodsTo unbiasedly identify immune cells and states associated with irAEs, we applied CITE-seq to measure transcripts and surface proteins (83 protein markers) from PBMCs collected from patients with thymic epithelial tumors before and after treatment with an anti-PD-L1 antibody (avelumab, NCT01772004, NCT03076554).ResultsSamples from 9 patients were analyzed. No patient had a history of pre-existing paraneoplastic autoimmune disease. Anti-tumor activity was observed in all cases, and 5 patients had clinical and/or biochemical evidence of immune-related muscle inflammation (myositis with or without myocarditis). Multilevel models applied within highly resolved cell clusters revealed transcriptional states associated with ICI response and more uniquely with irAEs. A total of 190,000 cells were included in the analysis after quality control. Most notably, CD45RA+ effector memory CD8 T cells with an mTOR transcriptional signature were highly enriched at baseline and post treatment in patients with irAEs.ConclusionsOur findings suggest the potential therapeutic avenues by using mTOR inhibitors to dampen autoimmune responses while potentially sparing anti-tumor activity, to prevent treatment discontinuation and improve clinical outcomes for cancer patients treated with ICIs.AcknowledgementsThis research was supported in part by the Intramural Research Program of the NCI (the Center for Cancer Research), NIAID and NIAMS, and through a Cooperative Research and Development Agreement between the National Cancer Institute and EMD Serono.Trial RegistrationNCT01772004, NCT03076554Ethics ApprovalThis study is approved by NCI institutional review board.


Cancers ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 738 ◽  
Author(s):  
Raju K. Vaddepally ◽  
Prakash Kharel ◽  
Ramesh Pandey ◽  
Rohan Garje ◽  
Abhinav B. Chandra

Cancer is associated with higher morbidity and mortality and is the second leading cause of death in the US. Further, in some nations, cancer has overtaken heart disease as the leading cause of mortality. Identification of molecular mechanisms by which cancerous cells evade T cell-mediated cytotoxic damage has led to the modern era of immunotherapy in cancer treatment. Agents that release these immune brakes have shown activity to recover dysfunctional T cells and regress various cancer. Both cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) and Programmed Death-1 (PD-1) play their role as physiologic brakes on unrestrained cytotoxic T effector function. CTLA-4 (CD 152) is a B7/CD28 family; it mediates immunosuppression by indirectly diminishing signaling through the co-stimulatory receptor CD28. Ipilimumab is the first and only FDA-approved CTLA-4 inhibitor; PD-1 is an inhibitory transmembrane protein expressed on T cells, B cells, Natural Killer cells (NKs), and Myeloid-Derived Suppressor Cells (MDSCs). Programmed Death-Ligand 1 (PD-L1) is expressed on the surface of multiple tissue types, including many tumor cells and hematopoietic cells. PD-L2 is more restricted to hematopoietic cells. Blockade of the PD-1 /PDL-1 pathway can enhance anti-tumor T cell reactivity and promotes immune control over the cancerous cells. Since the FDA approval of ipilimumab (human IgG1 k anti-CTLA-4 monoclonal antibody) in 2011, six more immune checkpoint inhibitors (ICIs) have been approved for cancer therapy. PD-1 inhibitors nivolumab, pembrolizumab, cemiplimab and PD-L1 inhibitors atezolizumab, avelumab, and durvalumab are in the current list of the approved agents in addition to ipilimumab. In this review paper, we discuss the role of each immune checkpoint inhibitor (ICI), the landmark trials which led to their FDA approval, and the strength of the evidence per National Comprehensive Cancer Network (NCCN), which is broadly utilized by medical oncologists and hematologists in their daily practice.


2017 ◽  
Vol 35 (15_suppl) ◽  
pp. 2035-2035 ◽  
Author(s):  
Basak Oyan ◽  
Seyma Eren ◽  
Ozlem Sonmez ◽  
Ferda Ozkan ◽  
Kaan Yaltırak ◽  
...  

2035 Background: PD-L1 expression status is the main predictive factor for response to immune checkpoint inhibitors. PD-L1 status may change over time with the impact of therapies. The aim of this study is to determine if PD-L1 expression status changes in recurrent gliomas after chemoradiotherapy. Methods: Thirty eight patients with recurrent high grade gliomas who had surgical excision at least two times were included in this retrospective cross-sectional study. Nine patients were excluded because of the lack of appropriate pathology slides for pathologic evaluation. PD-L1 expression of 29 patients was evaluated by an expert pathologist with immunohistochemical methods. PD-L1 positivity was defined as expression in ≥1% of tumor cells. Change in PD-L1 expression status was defined as an absolute 5% difference between two resections. Results: Of the 29 patients, 15 patients (51.7%) had PD-L1 expression in ≥1% of tumor cells and 7 patients (24.1%) had PD-L1 expression in ≥10% of tumor cells. Tumor PD-L1 expression (defined as expression in ≥1% of tumor cells) was positive in 15 (51.7%) of 29 patients at diagnosis and at the time of recurrence. The PD-L1 status did not change in 17 patients (58.6%). 8 patients had PD-L1 negative tumors both at diagnosis and at recurrence, while 9 patients had PD-L1 positive tumors both at diagnosis and at recurrence. In 6 patients (20.7%) a negative-to-positive switch and in 6 patients (20.7%) a positive to negative switch were seen. Tumor PD-L1 expression increased in 7 of 29 patients (24.1%) and decreased in 9 of 29 patients (31.1%). PD-L1 expression remained stable in 13 of 29 patients (34.4%). The change in PD-L1 status over time was not statistically significant. Conclusions: More than 50% of high grade glial tumors express PD-L1 at diagnosis, so these tumors are good candidates for immune checkpoint inhibitors. The expression status changes in more than 40% of high grade glial tumors at recurrence, so immune responsiveness of glial tumors can be modified by treatments like chemotherapy and radiotherapy.


2019 ◽  
Vol 37 (4_suppl) ◽  
pp. TPS178-TPS178
Author(s):  
Yukiya Narita ◽  
Hirokazu Shoji ◽  
Sadayuki Kawai ◽  
Takuro Mizukami ◽  
Michio Nakamura ◽  
...  

TPS178 Background: Immune checkpoint inhibitors are drugs that block specific proteins produced by the immune system cells, such as T-cells; these proteins prevent T-cells from killing cancer cells. NIV is a standard care for pretreated mGC patients (pts), with increasing clinical use in Japan. Data from retrospective studies on various tumors have shown that after exposure to immune checkpoint inhibitors, the objective response rate to CTx potentially improves; however, enough data have not been accumulated. Although there are no recommended CTx regimen following NIV therapy, in a clinical setting, an irinotecan or oxaliplatin combination regimen (limited to cisplatin-refractory or cisplatin-intolerant pts) is frequently used as post-NIV CTx. This multicenter observational study aims to evaluate the efficacy and safety of CTx in NIV-refractory or NIV-intolerant mGC pts. Methods: We prospectively collect clinical and imaging data from NIV-pretreated mGC pts; these pts will be treated with cytotoxic agents. Pts who meet inclusion criteria A (histologically proven mGC pretreated with NIV, prior administration of a combination therapy of fluoropyrimidine plus platinum and taxanes, and written informed consent) at primary registration are registered. After primary registration, pts who meet inclusion criteria B [Eastern Cooperative Oncology Group Performance Status (ECOG PS 0-2), refractory or intolerant to NIV; prior administration of irinotecan monotherapy or oxaliplatin combination regimens and prior use of cisplatin; evaluable lesions according to RECIST ver. 1.1] at formal registration are registered. The primary endpoint is overall survival of NIV-pretreated mGC pts after CTx. For this study, we require 146 pts, with bilateral alpha = 0.05 and beta = 0.10, with a median threshold survival of 4.0 months and an expected median survival of 6.0 months. Therefore, we plan to enroll 200 pts, considering exclusions from the analysis; since May 2018, we have enrolled 27 pts. Clinical trial information: UMIN000032182.


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